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Xu Y, Yang T, Xu Q, Tang Y, Yang Q. Vesicle-associated membrane protein 8 knockdown exerts anti-proliferative, pro-apoptotic, anti-autophagic, and pro-ferroptotic effects on colorectal cancer cells by inhibition of the JAK/STAT3 pathway. J Bioenerg Biomembr 2024; 56:419-431. [PMID: 38720136 DOI: 10.1007/s10863-024-10019-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 04/20/2024] [Indexed: 07/03/2024]
Abstract
Vesicle-associated membrane protein 8 (VAMP8), a soluble n-ethylmaleimide-sensitive factor receptor protein, acts as an oncogenic gene in the progression of several malignancies. Nevertheless, the roles and mechanisms of VAMP8 in colorectal cancer (CRC) progression remain unknown. The expression and prognostic significance of VAMP8 in CRC samples were analyzed through bioinformatics analyses. Cell proliferation was detected using CCK-8 and EdU incorporation assays and apoptosis was evaluated via flow cytometry. Western blot analysis was conducted to examine the protein expression. Ferroptosis was evaluated by measurement of iron metabolism, lipid peroxidation, and glutathione (GSH) content. VAMP8 was increased in CRC samples relative to normal samples on the basis of GEPIA and HPA databases. CRC patients with high level of VAMP8 had a worse overall survival. VAMP8 depletion led to a suppression of proliferation and promotion of apoptosis in CRC cells. Additionally, VAMP8 knockdown suppressed beclin1 expression and LC3-II/LC3-I ratio, elevated p62 expression, increased Fe2+, labile iron pool, lipid reactive oxygen species, and malondialdehyde levels, and repressed GSH content and glutathione peroxidase activity. Moreover, VAMP8 knockdown inhibited the activation of janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway in CRC cells. Mechanistically, activation of the JAK/STAT3 pathway by JAK1 or JAK2 overexpression attenuated VAMP8 silencing-mediated anti-proliferative, pro-apoptotic, anti-autophagic, and pro-ferroptotic effects on CRC cells. In conclusion, VAMP8 knockdown affects the proliferation, apoptosis, autophagy, and ferroptosis by the JAK/STAT3 pathway in CRC cells.
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Affiliation(s)
- Yi Xu
- Department of General Surgery, Nanyang First People's Hospital, Nanyang, China
| | - Tianyao Yang
- Department of General Surgery, Tiantai People's Hospital of Zhejiang Province, Taizhou, China
| | - Qiu Xu
- Department of Thyroid and Breast Surgery, Nanyang First People's Hospital, Nanyang, China
- Nanyang Key Laboratory of Thyroid Tumor Prevention and Treatment, Nanyang First People's Hospital, Nanyang, China
| | - Yan Tang
- Department of General Surgery, Nanyang First People's Hospital, Nanyang, China
| | - Qiong Yang
- General Surgery, Cancer Center, Department of Breast Surgery, Zhejiang Provincial People's Hospital, Affiliated People's Hospital, Hangzhou Medical College, Hangzhou, China.
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2
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Chen Y, Liu J, Kang S, Wei D, Fan Y, Xiang M, Liu X. A palisade-shaped membrane reservoir is required for rapid ring cell inflation in Drechslerella dactyloides. Nat Commun 2023; 14:7376. [PMID: 37968349 PMCID: PMC10651832 DOI: 10.1038/s41467-023-43235-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 11/03/2023] [Indexed: 11/17/2023] Open
Abstract
Fusion of individual vesicles carrying membrane-building materials with the plasma membrane (PM) enables gradual cell expansion and shape change. Constricting ring (CR) cells of carnivorous fungi triple in size within 0.1-1 s to capture passing nematodes. Here, we investigated how a carnivorous fungus, Drechslerella dactyloides, executes rapid and irreversible PM expansion during CR inflation. During CR maturation, vesicles carrying membrane-building materials accumulate and fuse, forming a structure named the Palisade-shaped Membrane-building Structure (PMS) around the rumen side of ring cells. After CR inflation, the PMS disappears, with partially inflated cells displaying wavy PM and fully inflated cells exhibiting smooth PM, suggesting that the PMS serves as the reservoir for membrane-building materials to enable rapid and extensive PM expansion. The DdSnc1, a v-SNARE protein, accumulates at the inner side of ring cells and is necessary for PMS formation and CR inflation. This study elucidates the unique cellular mechanisms underpinning rapid CR inflation.
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Affiliation(s)
- Yue Chen
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, 300071, China
| | - Jia Liu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, 300071, China
| | - Seogchan Kang
- Department of Plant Pathology & Environmental Microbiology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Dongsheng Wei
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, 300071, China
| | - Yani Fan
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Meichun Xiang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Xingzhong Liu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, 300071, China.
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
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3
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Luo ZY, Jiang TX, Zhang T, Xu P, Qiu XB. Ubiquitin Ligase Nrdp1 Controls Autophagy-Associated Acrosome Biogenesis and Mitochondrial Arrangement during Spermiogenesis. Cells 2023; 12:2211. [PMID: 37759433 PMCID: PMC10527437 DOI: 10.3390/cells12182211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/23/2023] [Accepted: 07/27/2023] [Indexed: 09/29/2023] Open
Abstract
Autophagy is critical to acrosome biogenesis and mitochondrial quality control, but the underlying mechanisms remain unclear. The ubiquitin ligase Nrdp1/RNF41 promotes ubiquitination of the mitophagy-associated Parkin and interacts with the pro-autophagic protein SIP/CacyBP. Here, we report that global deletion of Nrdp1 leads to formation of the round-headed sperm and male infertility by disrupting autophagy. Quantitative proteome analyses demonstrated that the expression of many proteins associated with mitochondria, lysosomes, and acrosomes was dysregulated in either spermatids or sperm of the Nrdp1-deficient mice. Deletion of Nrdp1 increased the levels of Parkin but decreased the levels of SIP, the mitochondrial fission protein Drp1 and the mitochondrial protein Tim23 in sperm, accompanied by the inhibition of autophagy, the impairment of acrosome biogenesis and the disruption of mitochondrial arrangement in sperm. Thus, our results uncover an essential role of Nrdp1 in spermiogenesis and male fertility by promoting autophagy, providing important clues to cope with the related male reproductive diseases.
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Affiliation(s)
- Zi-Yu Luo
- Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, College of Life Sciences, Beijing Normal University, 19 Xinjiekouwai Avenue, Beijing 100875, China; (Z.-Y.L.); (T.-X.J.)
| | - Tian-Xia Jiang
- Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, College of Life Sciences, Beijing Normal University, 19 Xinjiekouwai Avenue, Beijing 100875, China; (Z.-Y.L.); (T.-X.J.)
| | - Tao Zhang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Institute of Lifeomics, 38 Science Park Road, Beijing 102206, China;
| | - Ping Xu
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Institute of Lifeomics, 38 Science Park Road, Beijing 102206, China;
| | - Xiao-Bo Qiu
- Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, College of Life Sciences, Beijing Normal University, 19 Xinjiekouwai Avenue, Beijing 100875, China; (Z.-Y.L.); (T.-X.J.)
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4
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Wu J, Xing L, Zheng Y, Yu Y, Wu R, Liu X, Li L, Huang Y. Disease-specific protein corona formed in pathological intestine enhances the oral absorption of nanoparticles. Acta Pharm Sin B 2023; 13:3876-3891. [PMID: 37719377 PMCID: PMC10501873 DOI: 10.1016/j.apsb.2023.02.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 01/25/2023] [Accepted: 02/06/2023] [Indexed: 03/06/2023] Open
Abstract
Protein corona (PC) has been identified to impede the transportation of intravenously injected nanoparticles (NPs) from blood circulation to their targeted sites. However, how intestinal PC (IPC) affects the delivery of orally administered NPs are still needed to be elucidated. Here, we found that IPC exerted "positive effect" or "negative effect" depending on different pathological conditions in the gastrointestinal tract. We prepared polystyrene nanoparticles (PS) adsorbed with different IPC derived from the intestinal tract of healthy, diabetic, and colitis rats (H-IPC@PS, D-IPC@PS, C-IPC@PS). Proteomics analysis revealed that, compared with healthy IPC, the two disease-specific IPC consisted of a higher proportion of proteins that were closely correlated with transepithelial transport across the intestine. Consequently, both D-IPC@PS and C-IPC@PS mainly exploited the recycling endosome and ER-Golgi mediated secretory routes for intracellular trafficking, which increased the transcytosis from the epithelium. Together, disease-specific IPC endowed NPs with higher intestinal absorption. D-IPC@PS posed "positive effect" on intestinal absorption into blood circulation for diabetic therapy. Conversely, C-IPC@PS had "negative effect" on colitis treatment because of unfavorable absorption in the intestine before arriving colon. These results imply that different or even opposite strategies to modulate the disease-specific IPC need to be adopted for oral nanomedicine in the treatment of variable diseases.
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Affiliation(s)
- Jiawei Wu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Liyun Xing
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yaxian Zheng
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yinglan Yu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Ruinan Wu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Xi Liu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Lian Li
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yuan Huang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
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5
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Cheng X, Huang R, Huang S, Fan W, Yuan R, Wang X, Zhang X. Recent advances in ocular graft-versus-host disease. Front Immunol 2023; 14:1092108. [PMID: 36761771 PMCID: PMC9905686 DOI: 10.3389/fimmu.2023.1092108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 01/10/2023] [Indexed: 01/26/2023] Open
Abstract
Ocular graft-versus-host-disease (GVHD) remains a significant clinical complication after allogeneic hematopoietic stem cell transplantation. Impaired visual function, pain, and other symptoms severely affect affected individuals' quality of life. However, the diagnosis of and therapy for ocular GVHD involve a multidisciplinary approach and remain challenging for both hematologists and ophthalmologists, as there are no unified international criteria. Through an exploration of the complex pathogenesis of ocular GVHD, this review comprehensively summarizes the pathogenic mechanism, related tear biomarkers, and clinical characteristics of this disease. Novel therapies based on the mechanisms are also discussed to provide insights into the ocular GVHD treatment.
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Affiliation(s)
- Xianjing Cheng
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, Army Medical University, Chongqing, China.,School of Medicine, Chongqing University, Chongqing, China
| | - Ruihao Huang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, Army Medical University, Chongqing, China
| | - Shiqin Huang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, Army Medical University, Chongqing, China
| | - Wei Fan
- Department of Ophthalmology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Rongdi Yuan
- Department of Ophthalmology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Xiaoqi Wang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, Army Medical University, Chongqing, China
| | - Xi Zhang
- Medical Center of Hematology, Xinqiao Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, Army Medical University, Chongqing, China.,School of Medicine, Chongqing University, Chongqing, China.,Jinfeng Laboratory, Chongqing, China
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6
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Yan C, Jiang J, Yang Y, Geng X, Dong W. The function of VAMP2 in mediating membrane fusion: An overview. Front Mol Neurosci 2022; 15:948160. [PMID: 36618823 PMCID: PMC9816800 DOI: 10.3389/fnmol.2022.948160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022] Open
Abstract
Vesicle-associated membrane protein 2 (VAMP2, also known as synaptobrevin-2), encoded by VAMP2 in humans, is a key component of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex. VAMP2 combined with syntaxin-1A (SYX-1A) and synaptosome-associated protein 25 (SNAP-25) produces a force that induces the formation of fusion pores, thereby mediating the fusion of synaptic vesicles and the release of neurotransmitters. VAMP2 is largely unstructured in the absence of interaction partners. Upon interaction with other SNAREs, the structure of VAMP2 stabilizes, resulting in the formation of four structural domains. In this review, we highlight the current knowledge of the roles of the VAMP2 domains and the interaction between VAMP2 and various fusion-related proteins in the presynaptic cytoplasm during the fusion process. Our summary will contribute to a better understanding of the roles of the VAMP2 protein in membrane fusion.
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Affiliation(s)
- Chong Yan
- Key Laboratory of Medical Electrophysiology, Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan, China
| | - Jie Jiang
- Key Laboratory of Medical Electrophysiology, Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan, China
| | - Yuan Yang
- Key Laboratory of Medical Electrophysiology, Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan, China
| | - Xiaoqi Geng
- Department of Neurosurgery, Neurosurgical Clinical Research Center of Sichuan Province, Affiliated Hospital of Southwest Medical University, Luzhou, China,*Correspondence: Xiaoqi Geng,
| | - Wei Dong
- Key Laboratory of Medical Electrophysiology, Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan, China,Wei Dong,
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7
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Alfonso-Pérez T, Baonza G, Herranz G, Martín-Belmonte F. Deciphering the interplay between autophagy and polarity in epithelial tubulogenesis. Semin Cell Dev Biol 2022; 131:160-172. [PMID: 35641407 DOI: 10.1016/j.semcdb.2022.05.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/17/2022] [Accepted: 05/18/2022] [Indexed: 12/14/2022]
Abstract
The Metazoan complexity arises from a primary building block, the epithelium, which comprises a layer of polarized cells that divide the organism into compartments. Most of these body compartments are organs formed by epithelial tubes that enclose an internal hollow space or lumen. Over the last decades, multiple studies have unmasked the paramount events required to form this lumen de novo. In epithelial cells, these events mainly involve recognizing external clues, establishing and maintaining apicobasal polarity, endo-lysosomal trafficking, and expanding the created lumen. Although canonical autophagy has been classically considered a catabolic process needed for cell survival, multiple studies have also emphasized its crucial role in epithelial polarity, morphogenesis and cellular homeostasis. Furthermore, non-canonical autophagy pathways have been recently discovered as atypical secretory routes. Both canonical and non-canonical pathways play essential roles in epithelial polarity and lumen formation. This review addresses how the molecular machinery for epithelial polarity and autophagy interplay in different processes and how autophagy functions influence lumenogenesis, emphasizing its role in the lumen formation key events.
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Affiliation(s)
- Tatiana Alfonso-Pérez
- Program of Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo, Ochoa", CSIC-UAM, Madrid 28049, Spain; Ramon & Cajal Health Research Institute (IRYCIS), Hospital Universitario Ramón y Cajal, Madrid 28034, Spain
| | - Gabriel Baonza
- Program of Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo, Ochoa", CSIC-UAM, Madrid 28049, Spain
| | - Gonzalo Herranz
- Program of Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo, Ochoa", CSIC-UAM, Madrid 28049, Spain; Ramon & Cajal Health Research Institute (IRYCIS), Hospital Universitario Ramón y Cajal, Madrid 28034, Spain
| | - Fernando Martín-Belmonte
- Program of Tissue and Organ Homeostasis, Centro de Biología Molecular "Severo, Ochoa", CSIC-UAM, Madrid 28049, Spain; Ramon & Cajal Health Research Institute (IRYCIS), Hospital Universitario Ramón y Cajal, Madrid 28034, Spain.
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8
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Zhu M, Xu H, Jiang Y, Yu H, Liu Y. Epigallocatechin gallate inhibits SNARE-dependent membrane fusion by blocking trans-SNARE assembly. FEBS Open Bio 2022; 12:2111-2121. [PMID: 36111501 PMCID: PMC9714361 DOI: 10.1002/2211-5463.13488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/06/2022] [Accepted: 09/15/2022] [Indexed: 01/25/2023] Open
Abstract
Insulin secretion is a signal-triggered process that requires membrane fusion between the secretory granules and plasma membrane in pancreatic β cells. The exocytosis of insulin is mediated by target-soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs) on the plasma membrane and vesicle-SNAREs on the vesicles, which assemble into a quaternary trans-SNARE complex to initiate the fusion. Expression of fusion proteins is reduced in the islets of patients with type II diabetes, indicating that SNARE-mediated fusion defect is closely related to insulin-based metabolic diseases. Previous studies have suggested that epigallocatechin gallate (EGCG) has an inhibitory effect on membrane fusion. In the present study, we performed in vitro reconstitution assays to unravel the molecular mechanisms of EGCG in SNARE-mediated insulin secretory vesicle fusion. Our data show that EGCG efficiently inhibits insulin secretory SNARE-mediated membrane fusion. Mechanistic studies indicated that EGCG blocks the formation of the trans-SNARE complex. Furthermore, calcium/synaptotagmin-7-stimulated fusion kinetics were largely reduced by EGCG, confirming that it is a potential regulator of SNARE-dependent insulin secretion. Our findings suggest that the trans-SNARE complex might be a promising target for controlling SNARE-dependent vesicle fusion.
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Affiliation(s)
- Min Zhu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life SciencesNanjing Normal UniversityChina
| | - Han Xu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life SciencesNanjing Normal UniversityChina
| | - Yuting Jiang
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life SciencesNanjing Normal UniversityChina
| | - Haijia Yu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life SciencesNanjing Normal UniversityChina
| | - Yinghui Liu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life SciencesNanjing Normal UniversityChina
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9
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Three live-imaging techniques for comprehensively understanding the initial trigger for insulin-responsive intracellular GLUT4 trafficking. iScience 2022; 25:104164. [PMID: 35434546 PMCID: PMC9010770 DOI: 10.1016/j.isci.2022.104164] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 11/16/2021] [Accepted: 03/24/2022] [Indexed: 01/31/2023] Open
Abstract
Quantitative features of GLUT4 glucose transporter's behavior deep inside cells remain largely unknown. Our previous analyses with live-cell imaging of intracellular GLUT4 trafficking demonstrated two crucial early events responsible for triggering insulin-responsive translocation processes, namely, heterotypic fusion and liberation. To quantify the regulation, interrelationships, and dynamics of the initial events more accurately and comprehensively, we herein applied three analyses, each based on our distinct dual-color live-cell imaging approaches. With these approaches, heterotypic fusion was found to be the first trigger for insulin-responsive GLUT4 redistributions, preceding liberation, and to be critically regulated by Akt substrate of 160 kDa (AS160) and actin dynamics. In addition, demonstrating the subcellular regional dependence of GLUT4 dynamics revealed that liberated GLUT4 molecules are promptly incorporated into the trafficking itinerary of transferrin receptors. Our approaches highlight the physiological significance of endosomal "GLUT4 molecule trafficking" rather than "GLUT4 vesicle delivery" to the plasma membrane in response to insulin.
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10
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Colorectal cancer in Crohn's disease evaluated with genes belonging to fibroblasts of the intestinal mucosa selected by NMF. Pathol Res Pract 2021; 229:153728. [PMID: 34953405 DOI: 10.1016/j.prp.2021.153728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 11/26/2021] [Accepted: 11/27/2021] [Indexed: 12/16/2022]
Abstract
Crohn's disease (CD) is a type of chronic, inflammatory bowel disease (IBD) which affects any part of the gastrointestinal tract. This study aims to understand the mechanism which activate mucosal fibroblasts in the microenvironment of the colon in CD and colorectal carcinomas and to extract fibroblasts phenotypes via a novel framework based on non-negative factorization of matrix (NMF). The results identify a fibroblast phenotype characterized by intense pro-inflammatory activity ensured by the presence of genes belonging to the APOBEC1 family, such as APOBEC3F and APOBEC3G. These results demonstrated that there is a difference in fibroblast response in producing a pro-tumorigenic effect in CD. The different activation mechanisms could represent useful biomarkers in controlling CD development without generalizing its significance as IBD.
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Cyge B, Voronina V, Hoque M, Kim EN, Hall J, Bailey-Lundberg JM, Pazour GJ, Crawford HC, Moon RT, Li FQ, Takemaru KI. Loss of the ciliary protein Chibby1 in mice leads to exocrine pancreatic degeneration and pancreatitis. Sci Rep 2021; 11:17220. [PMID: 34446743 PMCID: PMC8390639 DOI: 10.1038/s41598-021-96597-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 08/12/2021] [Indexed: 12/12/2022] Open
Abstract
Primary cilia protrude from the apical surface of many cell types and act as a sensory organelle that regulates diverse biological processes ranging from chemo- and mechanosensation to signaling. Ciliary dysfunction is associated with a wide array of genetic disorders, known as ciliopathies. Polycystic lesions are commonly found in the kidney, liver, and pancreas of ciliopathy patients and mouse models. However, the pathogenesis of the pancreatic phenotype remains poorly understood. Chibby1 (Cby1), a small conserved coiled-coil protein, localizes to the ciliary base and plays a crucial role in ciliogenesis. Here, we report that Cby1-knockout (KO) mice develop severe exocrine pancreatic atrophy with dilated ducts during early postnatal development. A significant reduction in the number and length of cilia was observed in Cby1-KO pancreta. In the adult Cby1-KO pancreas, inflammatory cell infiltration and fibrosis were noticeable. Intriguingly, Cby1-KO acinar cells showed an accumulation of zymogen granules (ZGs) with altered polarity. Moreover, isolated acini from Cby1-KO pancreas exhibited defective ZG secretion in vitro. Collectively, our results suggest that, upon loss of Cby1, concomitant with ciliary defects, acinar cells accumulate ZGs due to defective exocytosis, leading to cell death and progressive exocrine pancreatic degeneration after birth.
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Affiliation(s)
- Benjamin Cyge
- Graduate Program in Molecular and Cellular Pharmacology, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Vera Voronina
- Department of Pharmacology, Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine and Howard Hughes Medical Institute, Seattle, WA, 98195, USA
| | - Mohammed Hoque
- Graduate Program in Molecular and Cellular Biology, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Eunice N Kim
- Graduate Program in Molecular and Cellular Biology, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Jason Hall
- Department of Cancer Biology, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Jennifer M Bailey-Lundberg
- Department of Anesthesiology, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Gregory J Pazour
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Howard C Crawford
- Department of Cancer Biology, Mayo Clinic, Jacksonville, FL, 32224, USA
- Henry Ford Health System, Detroit, MI, 48202, USA
| | - Randall T Moon
- Department of Pharmacology, Institute for Stem Cell and Regenerative Medicine, University of Washington School of Medicine and Howard Hughes Medical Institute, Seattle, WA, 98195, USA
| | - Feng-Qian Li
- Graduate Program in Molecular and Cellular Pharmacology, Stony Brook University, Stony Brook, NY, 11794, USA
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, 11974, USA
| | - Ken-Ichi Takemaru
- Graduate Program in Molecular and Cellular Pharmacology, Stony Brook University, Stony Brook, NY, 11794, USA.
- Graduate Program in Molecular and Cellular Biology, Stony Brook University, Stony Brook, NY, 11794, USA.
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, 11974, USA.
- Department of Pharmacological Sciences, Stony Brook University, BST 7-182, 101 Nicolls Rd., Stony Brook, NY, 11794-8651, USA.
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12
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Role of SNAREs in Neurodegenerative Diseases. Cells 2021; 10:cells10050991. [PMID: 33922505 PMCID: PMC8146804 DOI: 10.3390/cells10050991] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/18/2021] [Accepted: 04/20/2021] [Indexed: 02/06/2023] Open
Abstract
Neurodegenerative diseases are pathologies of the central and peripheral nervous systems characterized by loss of brain functions and problems in movement which occur due to the slow and progressive degeneration of cellular elements. Several neurodegenerative diseases are known such as Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis and many studies on the molecular mechanisms underlying these pathologies have been conducted. Altered functions of some key proteins and the presence of intraneuronal aggregates have been identified as responsible for the development of the diseases. Interestingly, the formation of the SNARE complex has been discovered to be fundamental for vesicle fusion, vesicle recycling and neurotransmitter release. Indeed, inhibition of the formation of the SNARE complex, defects in the SNARE-dependent exocytosis and altered regulation of SNARE-mediated vesicle fusion have been associated with neurodegeneration. In this review, the biological aspects of neurodegenerative diseases and the role of SNARE proteins in relation to the onset of these pathologies are described.
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13
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Scales SJ, Gupta N, De Mazière AM, Posthuma G, Chiu CP, Pierce AA, Hötzel K, Tao J, Foreman O, Koukos G, Oltrabella F, Klumperman J, Lin W, Peterson AS. Apolipoprotein L1-Specific Antibodies Detect Endogenous APOL1 inside the Endoplasmic Reticulum and on the Plasma Membrane of Podocytes. J Am Soc Nephrol 2020; 31:2044-2064. [PMID: 32764142 DOI: 10.1681/asn.2019080829] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 05/10/2020] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND APOL1 is found in human kidney podocytes and endothelia. Variants G1 and G2 of the APOL1 gene account for the high frequency of nondiabetic CKD among African Americans. Proposed mechanisms of kidney podocyte cytotoxicity resulting from APOL1 variant overexpression implicate different subcellular compartments. It is unclear where endogenous podocyte APOL1 resides, because previous immunolocalization studies utilized overexpressed protein or commercially available antibodies that crossreact with APOL2. This study describes and distinguishes the locations of both APOLs. METHODS Immunohistochemistry, confocal and immunoelectron microscopy, and podocyte fractionation localized endogenous and transfected APOL1 using a large panel of novel APOL1-specific mouse and rabbit monoclonal antibodies. RESULTS Both endogenous podocyte and transfected APOL1 isoforms vA and vB1 (and a little of isoform vC) localize to the luminal face of the endoplasmic reticulum (ER) and to the cell surface, but not to mitochondria, endosomes, or lipid droplets. In contrast, APOL2, isoform vB3, and most vC of APOL1 localize to the cytoplasmic face of the ER and are consequently absent from the cell surface. APOL1 knockout podocytes do not stain for APOL1, attesting to the APOL1-specificity of the antibodies. Stable re-transfection of knockout podocytes with inducible APOL1-G0, -G1, and -G2 showed no differences in localization among variants. CONCLUSIONS APOL1 is found in the ER and plasma membrane, consistent with either the ER stress or surface cation channel models of APOL1-mediated cytotoxicity. The surface localization of APOL1 variants potentially opens new therapeutic targeting avenues.
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Affiliation(s)
- Suzie J Scales
- Department of Molecular Biology, Genentech, South San Francisco, California .,Department of Immunology, Genentech, South San Francisco, California
| | - Nidhi Gupta
- Department of Molecular Biology, Genentech, South San Francisco, California.,Department of Immunology, Genentech, South San Francisco, California
| | - Ann M De Mazière
- Section of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - George Posthuma
- Section of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Cecilia P Chiu
- Department of Antibody Engineering, Genentech, South San Francisco, California
| | - Andrew A Pierce
- Department of Pathology, Genentech, South San Francisco, California
| | - Kathy Hötzel
- Department of Pathology, Genentech, South San Francisco, California
| | - Jianhua Tao
- Department of Pathology, Genentech, South San Francisco, California
| | - Oded Foreman
- Department of Pathology, Genentech, South San Francisco, California
| | - Georgios Koukos
- Department of Molecular Biology, Genentech, South San Francisco, California
| | | | - Judith Klumperman
- Section of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - WeiYu Lin
- Department of Antibody Engineering, Genentech, South San Francisco, California
| | - Andrew S Peterson
- Department of Molecular Biology, Genentech, South San Francisco, California
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14
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Thayer A, Murataeva N, Delcroix V, Wager-Miller J, Makarenkova HP, Straiker A. THC Regulates Tearing via Cannabinoid CB1 Receptors. Invest Ophthalmol Vis Sci 2020; 61:48. [PMID: 32852544 PMCID: PMC7452851 DOI: 10.1167/iovs.61.10.48] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Aqueous deficiency dry eye (ADDE) is a chronic condition affecting millions, with symptoms ranging from a dry itchiness to blurred vision and accompanied by an increased risk of eye infections. ADDE typically arises from disorders of the lacrimal gland that produces tears necessary for eye lubrication. Cannabis users frequently report dry eye, but the basis for this is unknown. If the effects occur via the endogenous cannabinoid signaling system, then this may represent a novel mechanism for the regulation of tearing. Methods We examined expression of cannabinoid CB1 receptors in the lacrimal gland using immunohistochemistry, Western blotting, and PCR and tested tetrahydrocannabinol (THC) regulation of tearing in wild-type and CB1-null mice. Results We now report that CB1 receptors are expressed in the axons of cholinergic neurons innervating the lacrimal gland. Little if any staining is seen in lacrimal gland epithelial cells (acinar and ductal) or myoepithelial cells (MECs). Activation of CB1 receptors by THC or the cannabinoid agonist CP55940 reduces tearing in male mice. In female mice, THC has no effect, but CP55940 increases tearing. In both sexes, the effect of CP55940 is absent in CB1 knockout mice. CB1 mRNA and protein levels are approximately four- to fivefold higher in males than females. In male knockouts, THC increases tearing, suggesting that THC also acts through different receptors. Conclusions Our results suggest a novel, albeit sex-dependent, physiologic basis for the dry eye symptoms experienced by cannabis users: activation of neuronal CB1 receptors in the lacrimal gland reduces tearing.
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Affiliation(s)
- Amanda Thayer
- The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, United States.,Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana, United States
| | - Natalia Murataeva
- The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, United States.,Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana, United States
| | - Vanessa Delcroix
- Scripps Research Institute, Department of Molecular Medicine, La Jolla, California, United States
| | - Jim Wager-Miller
- The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, United States.,Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana, United States
| | - Helen P Makarenkova
- Scripps Research Institute, Department of Molecular Medicine, La Jolla, California, United States
| | - Alex Straiker
- The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, United States.,Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana, United States.,Program in Neuroscience, Indiana University, Bloomington, Indiana, United States
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15
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Malla SR, Krueger B, Wartmann T, Sendler M, Mahajan UM, Weiss FU, Thiel FG, De Boni C, Gorelick FS, Halangk W, Aghdassi AA, Reinheckel T, Gukovskaya AS, Lerch MM, Mayerle J. Early trypsin activation develops independently of autophagy in caerulein-induced pancreatitis in mice. Cell Mol Life Sci 2020; 77:1811-1825. [PMID: 31363815 PMCID: PMC8221268 DOI: 10.1007/s00018-019-03254-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 07/16/2019] [Accepted: 07/24/2019] [Indexed: 12/18/2022]
Abstract
Premature intrapancreatic trypsinogen activation is widely regarded as an initiating event for acute pancreatitis. Previous studies have alternatively implicated secretory vesicles, endosomes, lysosomes, or autophagosomes/autophagolysosomes as the primary site of trypsinogen activation, from which a cell-damaging proteolytic cascade originates. To identify the subcellular compartment of initial trypsinogen activation we performed a time-resolution analysis of the first 12 h of caerulein-induced pancreatitis in transgenic light chain 3 (LC3)-GFP autophagy reporter mice. Intrapancreatic trypsin activity increased within 60 min and serum amylase within 2 h, but fluorescent autophagosome formation only by 4 h of pancreatitis in parallel with a shift from cytosolic LC3-I to membranous LC3-II on Western blots. At 60 min, activated trypsin in heavier subcellular fractions was co-distributed with cathepsin B, but not with the autophagy markers LC3 or autophagy protein 16 (ATG16). Supramaximal caerulein stimulation of primary pancreatic acini derived from LC3-GFP mice revealed that trypsinogen activation is independent of autophagolysosome formation already during the first 15 min of exposure to caerulein. Co-localization studies (with GFP-LC3 autophagosomes versus Ile-Pro-Arg-AMC trypsin activity and immunogold-labelling of lysosomal-associated membrane protein 2 [LAMP-2] versus trypsinogen activation peptide [TAP]) indicated active trypsin in autophagolysosomes only at the later timepoints. In conclusion, during the initiating phase of caerulein-induced pancreatitis, premature protease activation develops independently of autophagolysosome formation and in vesicles arising from the secretory pathway. However, autophagy is likely to regulate overall intracellular trypsin activity during the later stages of this disease.
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Affiliation(s)
- Sudarshan R Malla
- Department of Medicine A, University Medicine Greifswald, Ferdinand-Sauerbruchstrasse, Greifswald, 17475, Germany
- Veterans Affairs Greater Los Angeles Healthcare System, David Geffen School of Medicine, Southern California Research Center for Alcoholic Liver and Pancreatic Disease and Cirrhosis, University of California at Los Angeles, Los Angeles, CA, 90073, USA
| | - Burkhard Krueger
- Division of Medical Biology, University of Rostock, Rostock, 18051, Germany
| | - Thomas Wartmann
- Division of Experimental Surgery, University of Magdeburg, Magdeburg, 39120, Germany
| | - Matthias Sendler
- Department of Medicine A, University Medicine Greifswald, Ferdinand-Sauerbruchstrasse, Greifswald, 17475, Germany
| | - Ujjwal M Mahajan
- Department of Medicine A, University Medicine Greifswald, Ferdinand-Sauerbruchstrasse, Greifswald, 17475, Germany
- Department of Medicine II, Ludwigs-Maximilians University Munich, 80539, Munich, Germany
| | - F Ulrich Weiss
- Department of Medicine A, University Medicine Greifswald, Ferdinand-Sauerbruchstrasse, Greifswald, 17475, Germany
| | - Franziska G Thiel
- Department of Medicine A, University Medicine Greifswald, Ferdinand-Sauerbruchstrasse, Greifswald, 17475, Germany
| | - Carina De Boni
- Division of Experimental Surgery, University of Magdeburg, Magdeburg, 39120, Germany
| | | | - Walter Halangk
- Division of Experimental Surgery, University of Magdeburg, Magdeburg, 39120, Germany
| | - Ali A Aghdassi
- Department of Medicine A, University Medicine Greifswald, Ferdinand-Sauerbruchstrasse, Greifswald, 17475, Germany
| | - Thomas Reinheckel
- Institute of Molecular Medicine and Cell Research, University of Freiburg, Freiburg, 79104, Germany
| | - Anna S Gukovskaya
- Veterans Affairs Greater Los Angeles Healthcare System, David Geffen School of Medicine, Southern California Research Center for Alcoholic Liver and Pancreatic Disease and Cirrhosis, University of California at Los Angeles, Los Angeles, CA, 90073, USA
| | - Markus M Lerch
- Department of Medicine A, University Medicine Greifswald, Ferdinand-Sauerbruchstrasse, Greifswald, 17475, Germany.
| | - Julia Mayerle
- Department of Medicine A, University Medicine Greifswald, Ferdinand-Sauerbruchstrasse, Greifswald, 17475, Germany
- Department of Medicine II, Ludwigs-Maximilians University Munich, 80539, Munich, Germany
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16
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Takahashi T, Miao Y, Kang F, Dolai S, Gaisano HY. Susceptibility Factors and Cellular Mechanisms Underlying Alcoholic Pancreatitis. Alcohol Clin Exp Res 2020; 44:777-789. [PMID: 32056245 DOI: 10.1111/acer.14304] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/03/2020] [Indexed: 12/16/2022]
Abstract
Alcohol is a major cause of acute and chronic pancreatitis. There have been some recent advances in the understanding of the mechanisms underlying alcoholic pancreatitis, which include perturbation in mitochondrial function and autophagy and ectopic exocytosis, with some of these cellular events involving membrane fusion soluble N-ethylmaleimide-sensitive factor receptor protein receptor proteins. Although new insights have been unraveled recently, the precise mechanisms remain complex, and their finer details have yet to be established. The overall pathophysiology of pancreatitis involves not only the pancreatic acinar cells but also the stellate cells and duct cells. Why only some are more susceptible to pancreatitis and with increased severity, while others are not, would suggest that there may be undefined protective factors or mechanisms that enhance recovery and regeneration after injury. Furthermore, there are confounding influences of lifestyle factors such as smoking and diet, and genetic background. Whereas alcohol and smoking cessation and a generally healthy lifestyle are intuitively the advice given to these patients afflicted with alcoholic pancreatitis in order to reduce disease recurrence and progression, there is as yet no specific treatment. A more complete understanding of the pathogenesis of pancreatitis from which novel therapeutic targets could be identified will have a great impact, particularly with the stubbornly high fatality (>30%) of severe pancreatitis. This review focuses on the susceptibility factors and underlying cellular mechanisms of alcohol injury on the exocrine pancreas.
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Affiliation(s)
- Toshimasa Takahashi
- From the, Departments of Medicine and Physiology, University of Toronto, Toronto, ON, Canada
| | - Yifan Miao
- From the, Departments of Medicine and Physiology, University of Toronto, Toronto, ON, Canada
| | - Fei Kang
- From the, Departments of Medicine and Physiology, University of Toronto, Toronto, ON, Canada
| | - Subhankar Dolai
- From the, Departments of Medicine and Physiology, University of Toronto, Toronto, ON, Canada
| | - Herbert Y Gaisano
- From the, Departments of Medicine and Physiology, University of Toronto, Toronto, ON, Canada
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17
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van Tol S, Atkins C, Bharaj P, Johnson KN, Hage A, Freiberg AN, Rajsbaum R. VAMP8 Contributes to the TRIM6-Mediated Type I Interferon Antiviral Response during West Nile Virus Infection. J Virol 2020; 94:e01454-19. [PMID: 31694946 PMCID: PMC6955268 DOI: 10.1128/jvi.01454-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 10/23/2019] [Indexed: 11/20/2022] Open
Abstract
Several members of the tripartite motif (TRIM) family of E3 ubiquitin ligases regulate immune pathways, including the antiviral type I interferon (IFN-I) system. Previously, we demonstrated that TRIM6 is involved in IFN-I induction and signaling. In the absence of TRIM6, optimal IFN-I signaling is reduced, allowing increased replication of interferon-sensitive viruses. Despite having evolved numerous mechanisms to restrict the vertebrate host's IFN-I response, West Nile virus (WNV) replication is sensitive to pretreatment with IFN-I. However, the regulators and products of the IFN-I pathway that are important in regulating WNV replication are incompletely defined. Consistent with WNV's sensitivity to IFN-I, we found that in TRIM6 knockout (TRIM6-KO) A549 cells, WNV replication is significantly increased and IFN-I induction and signaling are impaired compared to wild-type (wt) cells. IFN-β pretreatment was more effective in protecting against subsequent WNV infection in wt cells than TRIM6-KO, indicating that TRIM6 contributes to the establishment of an IFN-induced antiviral response against WNV. Using next-generation sequencing, we identified VAMP8 as a potential factor involved in this TRIM6-mediated antiviral response. VAMP8 knockdown resulted in reduced JAK1 and STAT1 phosphorylation and impaired induction of several interferon-stimulated genes (ISGs) following WNV infection or IFN-β treatment. Furthermore, VAMP8-mediated STAT1 phosphorylation required the presence of TRIM6. Therefore, the VAMP8 protein is a novel regulator of IFN-I signaling, and its expression and function are dependent on TRIM6 activity. Overall, these results provide evidence that TRIM6 contributes to the antiviral response against WNV and identify VAMP8 as a novel regulator of the IFN-I system.IMPORTANCE WNV is a mosquito-borne flavivirus that poses a threat to human health across large discontinuous areas throughout the world. Infection with WNV results in febrile illness, which can progress to severe neurological disease. Currently, there are no approved treatment options to control WNV infection. Understanding the cellular immune responses that regulate viral replication is important in diversifying the resources available to control WNV. Here, we show that the elimination of TRIM6 in human cells results in an increase in WNV replication and alters the expression and function of other components of the IFN-I pathway through VAMP8. Dissecting the interactions between WNV and host defenses both informs basic molecular virology and promotes the development of host- and virus-targeted antiviral strategies.
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Affiliation(s)
- Sarah van Tol
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Colm Atkins
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Preeti Bharaj
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Kendra N Johnson
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Adam Hage
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Alexander N Freiberg
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas, USA
- Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, Texas, USA
| | - Ricardo Rajsbaum
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas, USA
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18
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Hays CL, Grassmeyer JJ, Wen X, Janz R, Heidelberger R, Thoreson WB. Simultaneous Release of Multiple Vesicles from Rods Involves Synaptic Ribbons and Syntaxin 3B. Biophys J 2019; 118:967-979. [PMID: 31653448 DOI: 10.1016/j.bpj.2019.10.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/25/2019] [Accepted: 10/03/2019] [Indexed: 02/05/2023] Open
Abstract
First proposed as a specialized mode of release at sensory neurons possessing ribbon synapses, multivesicular release has since been described throughout the central nervous system. Many aspects of multivesicular release remain poorly understood. We explored mechanisms underlying simultaneous multivesicular release at ribbon synapses in salamander retinal rod photoreceptors. We assessed spontaneous release presynaptically by recording glutamate transporter anion currents (IA(glu)) in rods. Spontaneous IA(glu) events were correlated in amplitude and kinetics with simultaneously measured miniature excitatory postsynaptic currents in horizontal cells. Both measures indicated that a significant fraction of events is multiquantal, with an analysis of IA(glu) revealing that multivesicular release constitutes ∼30% of spontaneous release events. IA(glu) charge transfer increased linearly with event amplitude showing that larger events involve greater glutamate release. The kinetics of large and small IA(glu) events were identical as were rise times of large and small miniature excitatory postsynaptic currents, indicating that the release of multiple vesicles during large events is highly synchronized. Effects of exogenous Ca2+ buffers suggested that multiquantal, but not uniquantal, release occurs preferentially near Ca2+ channels clustered beneath synaptic ribbons. Photoinactivation of ribbons reduced the frequency of spontaneous multiquantal events without affecting uniquantal release frequency, showing that spontaneous multiquantal release requires functional ribbons. Although both occur at ribbon-style active zones, the absence of cross-depletion indicates that evoked and spontaneous multiquantal release from ribbons involve different vesicle pools. Introducing an inhibitory peptide into rods to interfere with the SNARE protein, syntaxin 3B, selectively reduced multiquantal event frequency. These results support the hypothesis that simultaneous multiquantal release from rods arises from homotypic fusion among neighboring vesicles on ribbons and involves syntaxin 3B.
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Affiliation(s)
- Cassandra L Hays
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska; Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska
| | - Justin J Grassmeyer
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska; Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska
| | - Xiangyi Wen
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska; West China Hospital, Sichuan University, Chengdu, Sichuan, P.R. China
| | - Roger Janz
- Department of Neurobiology and Anatomy, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas; The University of Texas MD Anderson Cancer Center University of Texas Health Graduate School of Biomedical Sciences, Houston, Texas
| | - Ruth Heidelberger
- Department of Neurobiology and Anatomy, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas; The University of Texas MD Anderson Cancer Center University of Texas Health Graduate School of Biomedical Sciences, Houston, Texas
| | - Wallace B Thoreson
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska; Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska.
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19
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Mayerle J, Sendler M, Hegyi E, Beyer G, Lerch MM, Sahin-Tóth M. Genetics, Cell Biology, and Pathophysiology of Pancreatitis. Gastroenterology 2019; 156:1951-1968.e1. [PMID: 30660731 PMCID: PMC6903413 DOI: 10.1053/j.gastro.2018.11.081] [Citation(s) in RCA: 147] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 02/07/2023]
Abstract
Since the discovery of the first trypsinogen mutation in families with hereditary pancreatitis, pancreatic genetics has made rapid progress. The identification of mutations in genes involved in the digestive protease-antiprotease pathway has lent additional support to the notion that pancreatitis is a disease of autodigestion. Clinical and experimental observations have provided compelling evidence that premature intrapancreatic activation of digestive proteases is critical in pancreatitis onset. However, disease course and severity are mostly governed by inflammatory cells that drive local and systemic immune responses. In this article, we review the genetics, cell biology, and immunology of pancreatitis with a focus on protease activation pathways and other early events.
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Affiliation(s)
- Julia Mayerle
- Medical Department II, University Hospital, LMU, Munich, Germany,Department of Medicine A, University Medicine Greifswald, Greifswald, Germany
| | - Matthias Sendler
- Department of Medicine A, University Medicine Greifswald, Greifswald, Germany
| | - Eszter Hegyi
- Institute for Translational Medicine, University of Pécs, Hungary
| | - Georg Beyer
- Medical Department II, University Hospital, LMU, Munich, Germany
| | - Markus M. Lerch
- Department of Medicine A, University Medicine Greifswald, Greifswald, Germany
| | - Miklós Sahin-Tóth
- Center for Exocrine Disorders, Department of Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, MA 02118
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20
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Klein O, Sagi-Eisenberg R. Anaphylactic Degranulation of Mast Cells: Focus on Compound Exocytosis. J Immunol Res 2019; 2019:9542656. [PMID: 31011586 PMCID: PMC6442490 DOI: 10.1155/2019/9542656] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 12/26/2018] [Indexed: 01/15/2023] Open
Abstract
Anaphylaxis is a notorious type 2 immune response which may result in a systemic response and lead to death. A precondition for the unfolding of the anaphylactic shock is the secretion of inflammatory mediators from mast cells in response to an allergen, mostly through activation of the cells via the IgE-dependent pathway. While mast cells are specialized secretory cells that can secrete through a variety of exocytic modes, the most predominant mode exerted by the mast cell during anaphylaxis is compound exocytosis-a specialized form of regulated exocytosis where secretory granules fuse to one another. Here, we review the modes of regulated exocytosis in the mast cell and focus on compound exocytosis. We review historical landmarks in the research of compound exocytosis in mast cells and the methods available for investigating compound exocytosis. We also review the molecular mechanisms reported to underlie compound exocytosis in mast cells and expand further with reviewing key findings from other cell types. Finally, we discuss the possible reasons for the mast cell to utilize compound exocytosis during anaphylaxis, the conflicting evidence in different mast cell models, and the open questions in the field which remain to be answered.
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Affiliation(s)
- Ofir Klein
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ronit Sagi-Eisenberg
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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21
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Schillemans M, Karampini E, Kat M, Bierings R. Exocytosis of Weibel-Palade bodies: how to unpack a vascular emergency kit. J Thromb Haemost 2019; 17:6-18. [PMID: 30375718 PMCID: PMC7379738 DOI: 10.1111/jth.14322] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Indexed: 01/17/2023]
Abstract
The blood vessel wall has a number of self-healing properties, enabling it to minimize blood loss and prevent or overcome infections in the event of vascular trauma. Endothelial cells prepackage a cocktail of hemostatic, inflammatory and angiogenic mediators in their unique secretory organelles, the Weibel-Palade bodies (WPBs), which can be immediately released on demand. Secretion of their contents into the vascular lumen through a process called exocytosis enables the endothelium to actively participate in the arrest of bleeding and to slow down and direct leukocytes to areas of inflammation. Owing to their remarkable elongated morphology and their secretory contents, which span the entire size spectrum of small chemokines all the way up to ultralarge von Willebrand factor multimers, WPBs constitute an ideal model system for studying the molecular mechanisms of secretory organelle biogenesis, exocytosis, and content expulsion. Recent studies have now shown that, during exocytosis, WPBs can undergo several distinct modes of fusion, and can utilize fundamentally different mechanisms to expel their contents. In this article, we discuss recent advances in our understanding of the composition of the WPB exocytotic machinery and how, because of its configuration, it is able to support WPB release in its various forms.
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Affiliation(s)
- M. Schillemans
- Molecular and Cellular HemostasisSanquin Research and Landsteiner LaboratoryAmsterdam UMCUniversity of AmsterdamAmsterdamthe Netherlands
| | - E. Karampini
- Molecular and Cellular HemostasisSanquin Research and Landsteiner LaboratoryAmsterdam UMCUniversity of AmsterdamAmsterdamthe Netherlands
| | - M. Kat
- Molecular and Cellular HemostasisSanquin Research and Landsteiner LaboratoryAmsterdam UMCUniversity of AmsterdamAmsterdamthe Netherlands
| | - R. Bierings
- Molecular and Cellular HemostasisSanquin Research and Landsteiner LaboratoryAmsterdam UMCUniversity of AmsterdamAmsterdamthe Netherlands
- HematologyErasmus University Medical CenterRotterdamthe Netherlands
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22
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Yuan M, Liao J, Luo J, Cui M, Jin F. Significance of Vesicle-Associated Membrane Protein 8 Expression in Predicting Survival in Breast Cancer. J Breast Cancer 2018; 21:399-405. [PMID: 30607161 PMCID: PMC6310720 DOI: 10.4048/jbc.2018.21.e57] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 09/21/2018] [Indexed: 12/23/2022] Open
Abstract
Purpose Vesicle-associated membrane protein 8 (VAMP8) is a soluble N-ethylmaleimide-sensitive factor receptor protein that participates in autophagy by directly regulating autophagosome membrane fusion and has been reported to be involved in tumor progression. Nevertheless, the expression and prognostic value of VAMP8 in breast cancer (BC) remain unknown. This study aimed to evaluate the clinical significance and biological function of VAMP8 in BC. Methods A total of 112 BC samples and 30 normal mammary gland samples were collected. The expression of VAMP8 was assessed in both BC tissues and normal mammary gland tissues via a two-step immunohistochemical detection method. Results The expression of VAMP8 in BC tissues was significantly higher than that in normal breast tissues. Furthermore, increased VAMP8 expression was significantly correlated with tumor size (p=0.007), lymph node metastasis (p=0.024) and recurrence (p=0.001). Patients with high VAMP8 expression had significantly lower cumulative recurrence-free survival and overall survival (p<0.001 for both) than patients with low VAMP8 expression. In multivariate logistic regression and Cox regression analyses, lymph node metastasis and VAMP8 expression were independent prognostic factors for BC. Conclusion VAMP8 is significantly upregulated in human BC tissues and can thus be a practical and potentially effective surrogate marker for survival in BC patients.
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Affiliation(s)
- Mengci Yuan
- Division of Breast Surgery, Department of Surgical Oncology, Research Unit of General Surgery, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Jianhua Liao
- Department of General Surgery, Zhejiang Hospital, Hangzhou, China
| | - Ji Luo
- Division of Breast Surgery, Department of Surgical Oncology, Research Unit of General Surgery, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Mengyao Cui
- Division of Breast Surgery, Department of Surgical Oncology, Research Unit of General Surgery, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Feng Jin
- Division of Breast Surgery, Department of Surgical Oncology, Research Unit of General Surgery, The First Affiliated Hospital of China Medical University, Shenyang, China
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VAMP8, a vesicle-SNARE required for RAB37-mediated exocytosis, possesses a tumor metastasis suppressor function. Cancer Lett 2018; 437:79-88. [PMID: 30165196 DOI: 10.1016/j.canlet.2018.08.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Accepted: 08/20/2018] [Indexed: 12/23/2022]
Abstract
We previously identified a metastasis suppressor RAB37 small GTPase that regulated exocytosis of tissue inhibitor of metalloproteinases 1 (TIMP1) to suppress lung cancer metastasis. Here, we show that vesicle-associated membrane protein 8 (VAMP8), a v-SNARE (vesicle soluble N-ethylmaleimide-sensitive factor activating protein receptor), interacts with RAB37 and drives the secretion of TIMP1 to inhibit tumor metastases. Confocal and total internal reflection fluorescence microscopic images demonstrated that VAMP8 co-localized with RAB37 and facilitated trafficking of RAB37-TIMP1 vesicles. Reconstitution experiments using tail-vein injection and lung-to-lung metastasis in mice showed that VAMP8 was essential for RAB37-regulated vesicle trafficking of TIMP1 to suppress cancer metastasis. Lung cancer patients with low VAMP8 showed distant metastasis, poor overall survival and progression-free survival. Importantly, multivariate Cox regression analysis indicated that patients with low VAMP8/low RAB37 expression profile showed significantly high risk of death (hazard ratio = 3.42, P < 0.001) even after adjusting for tumor metastasis parameter. Our findings reveal that VAMP8 is a novel v-SNARE crucial for RAB37-mediated exocytic transport of TIMP1 to suppress lung tumor metastasis. VAMP8 possesses a tumor metastasis suppressor function with a prognostic value in lung cancer.
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24
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Klein O, Roded A, Hirschberg K, Fukuda M, Galli SJ, Sagi-Eisenberg R. Imaging FITC-dextran as a Reporter for Regulated Exocytosis. J Vis Exp 2018. [PMID: 29985342 DOI: 10.3791/57936] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Regulated exocytosis is a process by which cargo, which is stored in secretory granules (SGs), is released in response to a secretory trigger. Regulated exocytosis is fundamental for intercellular communication and is a key mechanism for the secretion of neurotransmitters, hormones, inflammatory mediators, and other compounds, by a variety of cells. At least three distinct mechanisms are known for regulated exocytosis: full exocytosis, where a single SG fully fuses with the plasma membrane, kiss-and-run exocytosis, where a single SG transiently fuses with the plasma membrane, and compound exocytosis, where several SGs fuse with each other, prior to or after SG fusion with the plasma membrane. The type of regulated exocytosis undertaken by a cell is often dictated by the type of secretory trigger. However, in many cells, a single secretory trigger can activate multiple modes of regulated exocytosis simultaneously. Despite their abundance and importance across cell types and species, the mechanisms that determine the different modes of secretion are largely unresolved. One of the main challenges in investigating the different modes of regulated exocytosis, is the difficulty in distinguishing between them as well as exploring them separately. Here we describe the use of fluorescein isothiocyanate (FITC)-dextran as an exocytosis reporter, and live cell imaging, to differentiate between the different pathways of regulated exocytosis, focusing on compound exocytosis, based on the robustness and duration of the exocytic events.
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Affiliation(s)
- Ofir Klein
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University
| | - Amit Roded
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University
| | - Koret Hirschberg
- Department of Pathology, Sackler Faculty of Medicine, Tel Aviv University
| | - Mitsunori Fukuda
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University
| | - Stephen J Galli
- Departments of Pathology and of Microbiology and Immunology and Sean N. Parker Center for Allergy and Asthma Research, School of Medicine, Stanford University
| | - Ronit Sagi-Eisenberg
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University;
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25
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Schillemans M, Karampini E, van den Eshof BL, Gangaev A, Hofman M, van Breevoort D, Meems H, Janssen H, Mulder AA, Jost CR, Escher JC, Adam R, Carter T, Koster AJ, van den Biggelaar M, Voorberg J, Bierings R. Weibel-Palade Body Localized Syntaxin-3 Modulates Von Willebrand Factor Secretion From Endothelial Cells. Arterioscler Thromb Vasc Biol 2018; 38:1549-1561. [PMID: 29880488 PMCID: PMC6039413 DOI: 10.1161/atvbaha.117.310701] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 05/17/2018] [Indexed: 01/08/2023]
Abstract
Supplemental Digital Content is available in the text. Objective— Endothelial cells store VWF (von Willebrand factor) in rod-shaped secretory organelles, called Weibel-Palade bodies (WPBs). WPB exocytosis is coordinated by a complex network of Rab GTPases, Rab effectors, and SNARE (soluble NSF attachment protein receptor) proteins. We have previously identified STXBP1 as the link between the Rab27A-Slp4-a complex on WPBs and the SNARE proteins syntaxin-2 and -3. In this study, we investigate the function of syntaxin-3 in VWF secretion. Approach and Results— In human umbilical vein endothelial cells and in blood outgrowth endothelial cells (BOECs) from healthy controls, endogenous syntaxin-3 immunolocalized to WPBs. A detailed analysis of BOECs isolated from a patient with variant microvillus inclusion disease, carrying a homozygous mutation in STX3(STX3−/−), showed a loss of syntaxin-3 protein and absence of WPB-associated syntaxin-3 immunoreactivity. Ultrastructural analysis revealed no detectable differences in morphology or prevalence of immature or mature WPBs in control versus STX3−/− BOECs. VWF multimer analysis showed normal patterns in plasma of the microvillus inclusion disease patient, and media from STX3−/− BOECs, together indicating WPB formation and maturation are unaffected by absence of syntaxin-3. However, a defect in basal as well as Ca2+- and cAMP-mediated VWF secretion was found in the STX3−/− BOECs. We also show that syntaxin-3 interacts with the WPB-associated SNARE protein VAMP8 (vesicle-associated membrane protein-8). Conclusions— Our data reveal syntaxin-3 as a novel WPB-associated SNARE protein that controls WPB exocytosis.
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Affiliation(s)
- Maaike Schillemans
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
| | - Ellie Karampini
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
| | - Bart L van den Eshof
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
| | - Anastasia Gangaev
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
| | - Menno Hofman
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
| | - Dorothee van Breevoort
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
| | - Henriët Meems
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
| | - Hans Janssen
- Cell Biology, The Netherlands Cancer Institute, Amsterdam (H.J.)
| | - Aat A Mulder
- Molecular Cell Biology, Section Electron Microscopy, Leiden University Medical Center, The Netherlands (A.A.M., C.R.J., A.J.K.)
| | - Carolina R Jost
- Molecular Cell Biology, Section Electron Microscopy, Leiden University Medical Center, The Netherlands (A.A.M., C.R.J., A.J.K.)
| | - Johanna C Escher
- Pediatric Gastroenterology, Sophia Children's Hospital, Erasmus MC, Rotterdam, The Netherlands (J.C.E.)
| | - Rüdiger Adam
- Pediatric Gastroenterology, University Medical Centre, Mannheim, Germany (R.A.)
| | - Tom Carter
- St George's, University of London, United Kingdom (T.C.)
| | - Abraham J Koster
- Molecular Cell Biology, Section Electron Microscopy, Leiden University Medical Center, The Netherlands (A.A.M., C.R.J., A.J.K.)
| | - Maartje van den Biggelaar
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
| | - Jan Voorberg
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.).,Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, The Netherlands (J.V.)
| | - Ruben Bierings
- From the Plasma Proteins, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands (M.S., E.K., B.L.v.d.E., A.G., M.H., D.v.B., H.M., M.v.d.B., J.V., R.B.)
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26
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Dolai S, Liang T, Orabi AI, Holmyard D, Xie L, Greitzer-Antes D, Kang Y, Xie H, Javed TA, Lam PP, Rubin DC, Thorn P, Gaisano HY. Pancreatitis-Induced Depletion of Syntaxin 2 Promotes Autophagy and Increases Basolateral Exocytosis. Gastroenterology 2018; 154:1805-1821.e5. [PMID: 29360461 PMCID: PMC6461447 DOI: 10.1053/j.gastro.2018.01.025] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 12/13/2017] [Accepted: 01/08/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Pancreatic acinar cells are polarized epithelial cells that store enzymes required for digestion as inactive zymogens, tightly packed at the cell apex. Stimulation of acinar cells causes the zymogen granules to fuse with the apical membrane, and the cells undergo exocytosis to release proteases into the intestinal lumen. Autophagy maintains homeostasis of pancreatic acini. Syntaxin 2 (STX2), an abundant soluble N-ethyl maleimide sensitive factor attachment protein receptor in pancreatic acini, has been reported to mediate apical exocytosis. Using human pancreatic tissues and STX2-knockout (KO) mice, we investigated the functions of STX2 in zymogen granule-mediated exocytosis and autophagy. METHODS We obtained pancreatic tissues from 5 patients undergoing surgery for pancreatic cancer and prepared 80-μm slices; tissues were exposed to supramaximal cholecystokinin octapeptide (CCK-8) or ethanol and a low concentration of CCK-8 and analyzed by immunoblot and immunofluorescence analyses. STX2-KO mice and syntaxin 2+/+ C57BL6 mice (controls) were given intraperitoneal injections of supramaximal caerulein (a CCK-8 analogue) or fed ethanol and then given a low dose of caerulein to induce acute pancreatitis, or saline (controls); pancreata were isolated and analyzed by histology and immunohistochemistry. Acini were isolated from mice, incubated with CCK-8, and analyzed by immunofluorescence microscopy or used in immunoprecipitation experiments. Exocytosis was quantified using live-cell exocytosis and Ca2+ imaging analyses and based on formation of exocytotic soluble N-ethyl maleimide sensitive factor attachment protein receptor complexes. Dysregulations in autophagy were identified using markers, electron and immunofluorescence microscopy, and protease activation assays. RESULTS Human pancreatic tissues and dispersed pancreatic acini from control mice exposed to CCK-8 or ethanol plus CCK-8 were depleted of STX2. STX2-KO developed more severe pancreatitis after administration of supramaximal caerulein or a 6-week ethanol diet compared with control. Acini from STX2-KO mice had increased apical exocytosis after exposure to CCK-8, as well as increased basolateral exocytosis, which led to ectopic release of proteases. These increases in apical and basolateral exocytosis required increased formation of fusogenic soluble N-ethyl maleimide sensitive factor attachment protein receptor complexes, mediated by STX3 and STX4. STX2 bound ATG16L1 and prevented it from binding clathrin. Deletion of STX2 from acini increased binding of AT16L1 to clathrin, increasing formation of pre-autophagosomes and inducing autophagy. Induction of autophagy promoted the CCK-8-induced increase in autolysosome formation and the activation of trypsinogen. CONCLUSIONS In studies of human pancreatic tissues and pancreata from STX2-KO and control mice, we found STX2 to block STX3- and STX4-mediated fusion of zymogen granules with the plasma membrane and exocytosis and prevent binding of ATG16L1 to clathrin, which contributes to induction of autophagy. Exposure of pancreatic tissues to CCK-8 or ethanol depletes acinar cells of STX2, increasing basolateral exocytosis and promoting autophagy induction, leading to activation of trypsinogen.
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Affiliation(s)
- Subhankar Dolai
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
| | - Tao Liang
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Abrahim I Orabi
- Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Douglas Holmyard
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
| | - Li Xie
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | | | - Youhou Kang
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Huanli Xie
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Tanveer A Javed
- Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Patrick P Lam
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Deborah C Rubin
- Division of Gastroenterology, Departments of Medicine, and Developmental Biology, Washington University School of Medicine, St Louis, Missouri
| | - Peter Thorn
- University of Sydney, Sydney, New South Wales, Australia
| | - Herbert Y Gaisano
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Department of Physiology, University of Toronto, Toronto, Ontario, Canada.
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27
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Mu Y, Yan X, Li D, Zhao D, Wang L, Wang X, Gao D, Yang J, Zhang H, Li Y, Sun Y, Wei Y, Zhang Z, Chang X, Yao Z, Tian S, Zhang K, Terada LS, Ma Z, Liu Z. NUPR1 maintains autolysosomal efflux by activating SNAP25 transcription in cancer cells. Autophagy 2017; 14:654-670. [PMID: 29130426 DOI: 10.1080/15548627.2017.1338556] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
In the advanced stages of cancer, autophagy is thought to promote tumor progression through its ability to mitigate various cellular stresses. However, the details of how autophagy is homeostatically regulated in such tumors are unknown. Here, we report that NUPR1 (nuclear protein 1, transcriptional regulator), a transcriptional coregulator, is aberrantly expressed in a subset of cancer cells and predicts low overall survival rates for lung cancer patients. NUPR1 regulates the late stages of autolysosome processing through the induction of the SNARE protein SNAP25, which forms a complex with the lysosomal SNARE-associated protein VAMP8. NUPR1 depletion deregulates autophagic flux and impairs autolysosomal clearance, inducing massive cytoplasmic vacuolization and premature senescence in vitro and tumor suppression in vivo. Collectively, our data show that NUPR1 is a potent regulator of autolysosomal dynamics and is required for the progression of some epithelial cancers.
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Affiliation(s)
- Yanchao Mu
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Xiaojie Yan
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Ding Li
- c Laboratory of Epigenetics and Tumorigenesis, Tianjin Research Center of Basic Medical Sciences , Tianjin Medical University , Tianjin , 22 Qixiangtai Road, Heping District, Tianjin , China.,d Present address: Department of Clinical Laboratory , Tianjin Medical University Cancer Institute and Hospital , National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy , Tianjin , China
| | - Dan Zhao
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Lingling Wang
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Xiaoyang Wang
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China.,e Present address: Department of Internal Medicine , The Fifth Hospital of Shijiazhuang , Shijiazhuang , Hebei , China
| | - Dan Gao
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Jie Yang
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Hua Zhang
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Yanzhe Li
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Yanan Sun
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Yiliang Wei
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Zhenfa Zhang
- f Department of Lung Cancer , Lung Cancer Center, Tianjin Medical University Cancer Institute and Hospital , Tianjin , China
| | - Xinzhong Chang
- g Department of Breast Cancer , Breast Cancer Center, Tianjin Medical University Cancer Institute and Hospital , Tianjin , China
| | - Zhi Yao
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China.,b Key Laboratory of Immune Microenvironment and Disease of the Ministry of Education , Tianjin Medical University , Tianjin , China
| | - Shanshan Tian
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Kai Zhang
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China
| | - Lance S Terada
- h Department of Internal Medicine, Division of Pulmonary and Critical Care , University of Texas Southwestern Medical Center , Dallas , TX , USA
| | - Zhenyi Ma
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China.,i Key Laboratory of Hormones and Development (Ministry of Health) , Metabolic Diseases Hospital, Tianjin Institute of Endocrinology, Tianjin Medical University , Tianjin , China
| | - Zhe Liu
- a 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics , Tianjin Key Laboratory of Medical Epigenetics, Department of Immunology , Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University , Tianjin , China.,b Key Laboratory of Immune Microenvironment and Disease of the Ministry of Education , Tianjin Medical University , Tianjin , China.,c Laboratory of Epigenetics and Tumorigenesis, Tianjin Research Center of Basic Medical Sciences , Tianjin Medical University , Tianjin , 22 Qixiangtai Road, Heping District, Tianjin , China.,i Key Laboratory of Hormones and Development (Ministry of Health) , Metabolic Diseases Hospital, Tianjin Institute of Endocrinology, Tianjin Medical University , Tianjin , China
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28
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Dolai S, Liang T, Orabi AI, Xie L, Holmyard D, Javed TA, Fernandez NA, Xie H, Cattral MS, Thurmond DC, Thorn P, Gaisano HY. Depletion of the membrane-fusion regulator Munc18c attenuates caerulein hyperstimulation-induced pancreatitis. J Biol Chem 2017; 293:2510-2522. [PMID: 29284677 DOI: 10.1074/jbc.ra117.000792] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 12/21/2017] [Indexed: 12/26/2022] Open
Abstract
Epithelial pancreatic acinar cells perform crucial functions in food digestion, and acinar cell homeostasis required for secretion of digestive enzymes relies on SNARE-mediated exocytosis. The ubiquitously expressed Sec1/Munc18 protein mammalian uncoordinated-18c (Munc18c) regulates membrane fusion by activating syntaxin-4 (STX-4) to bind cognate SNARE proteins to form a SNARE complex that mediates exocytosis in many cell types. However, in the acinar cell, Munc18c's functions in exocytosis and homeostasis remain inconclusive. Here, we found that pancreatic acini from Munc18c-depleted mice (Munc18c+/-) and human pancreas (lenti-Munc18c-shRNA-treated) exhibit normal apical exocytosis of zymogen granules (ZGs) in response to physiologic stimulation with the intestinal hormone cholecystokinin (CCK-8). However, when stimulated with supraphysiologic CCK-8 levels to mimic pancreatitis, Munc18c-depleted (Munc18c+/-) mouse acini exhibited a reduction in pathological basolateral exocytosis of ZGs resulting from a decrease in fusogenic STX-4 SNARE complexes. This reduced basolateral exocytosis in part explained the less severe pancreatitis observed in Munc18c+/- mice after hyperstimulation with the CCK-8 analog caerulein. Likely as a result of this secretory blockade, Munc18c-depleted acini unexpectedly activated a component of the endoplasmic reticulum (ER) stress response that contributed to autophagy induction, resulting in downstream accumulation of autophagic vacuoles and autolysosomes. We conclude that Munc18c's role in mediating ectopic basolateral membrane fusion of ZGs contributes to the initiation of CCK-induced pancreatic injury, and that blockade of this secretory process could increase autophagy induction.
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Affiliation(s)
- Subhankar Dolai
- From the Departments of Medicine and .,Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Tao Liang
- From the Departments of Medicine and.,Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Abrahim I Orabi
- Division of Pediatric Gastroenterology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania 15224
| | - Li Xie
- From the Departments of Medicine and.,Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Douglas Holmyard
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | - Tanveer A Javed
- Division of Pediatric Gastroenterology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania 15224
| | | | | | - Mark S Cattral
- Toronto General Hospital Research Institute, University Health Network, University of Toronto, Toronto, Ontario M5G 2N2, Canada
| | - Debbie C Thurmond
- Beckman Research Institute of the City of Hope, Duarte, California 91010, and
| | - Peter Thorn
- School of Biomedical Sciences,University of Sydney, Sydney, New South Wales 2050, Australia
| | - Herbert Y Gaisano
- From the Departments of Medicine and .,Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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29
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Klein O, Roded A, Zur N, Azouz NP, Pasternak O, Hirschberg K, Hammel I, Roche PA, Yatsu A, Fukuda M, Galli SJ, Sagi-Eisenberg R. Rab5 is critical for SNAP23 regulated granule-granule fusion during compound exocytosis. Sci Rep 2017; 7:15315. [PMID: 29127297 PMCID: PMC5681557 DOI: 10.1038/s41598-017-15047-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 10/19/2017] [Indexed: 12/22/2022] Open
Abstract
Compound exocytosis is considered the most massive mode of exocytosis, during which the membranes of secretory granules (SGs) fuse with each other to form a channel through which the entire contents of their granules is released. The underlying mechanisms of compound exocytosis remain largely unresolved. Here we show that the small GTPase Rab5, a known regulator of endocytosis, is pivotal for compound exocytosis in mast cells. Silencing of Rab5 shifts receptor-triggered secretion from a compound to a full exocytosis mode, in which SGs individually fuse with the plasma membrane. Moreover, we show that Rab5 is essential for FcεRI-triggered association of the SNARE protein SNAP23 with the SGs. Direct evidence is provided for SNAP23 involvement in homotypic SG fusion that occurs in the activated cells. Finally, we show that this fusion event is prevented by inhibition of the IKKβ2 kinase, however, neither a phosphorylation-deficient nor a phosphomimetic mutant of SNAP23 can mediate homotypic SG fusion in triggered cells. Taken together our findings identify Rab5 as a heretofore-unrecognized regulator of compound exocytosis that is essential for SNAP23-mediated granule-granule fusion. Our results also implicate phosphorylation cycles in controlling SNAP23 SNARE function in homotypic SG fusion.
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Affiliation(s)
- Ofir Klein
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Amit Roded
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Neta Zur
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Nurit P Azouz
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.,Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
| | - Olga Pasternak
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Koret Hirschberg
- Department of Pathology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Ilan Hammel
- Department of Pathology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Paul A Roche
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Ayaka Yatsu
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi, 980-8578, Japan
| | - Mitsunori Fukuda
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi, 980-8578, Japan
| | - Stephen J Galli
- Departments of Pathology and of Microbiology and Immunology, and Sean N. Parker Center for Allergy and Asthma Research, Stanford University School of Medicine, Stanford, California, 94305-5176, USA
| | - Ronit Sagi-Eisenberg
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
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Reduced Expression of VAMP8 in Lacrimal Gland Affected by Chronic Graft-versus-Host Disease. J Ophthalmol 2017; 2017:1639012. [PMID: 29098081 PMCID: PMC5643041 DOI: 10.1155/2017/1639012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 08/01/2017] [Indexed: 01/06/2023] Open
Abstract
Purpose To investigate whether the SNARE protein vesicle-associated membrane protein 8 (VAMP8) was implicated in the development of chronic ocular graft-versus-host disease (GVHD). Methods Firstly, the chronic GVHD (cGVHD) and Sjögren's syndrome (SS)-impaired lacrimal gland (LG) tissue sections from humans for diagnostic purpose were evaluated for VAMP8 expression by histopathology and immunohistochemistry. Next, serial changes of tear secretion and VAMP8 expression at both protein and mRNA level of LG in an animal cGVHD model compared with the syngeneic control. Results Decreased VAMP 8 expression in the cGVHD-affected human LG was detected in comparison with SS-affected LG. Tear secretion in the murine cGVHD model was significantly reduced compared with that in the syngeneic controls 8 weeks after BMT. Protein expression of VAMP8 in the cGVHD-affected LG in murine cGVHD was decreased in comparison with that in the controls. Gene expression of VAMP8 in the cGVHD-affected murine LG was significantly less than that in the syngeneic control 3 weeks after BMT. Conclusions Our results suggested that expression of VAMP8 in the cGVHD-affected LG was decreased and accordingly tear secretion in cGVHD was reduced. Collectively, the reduction of VAMP8 expression in the cGVHD-affected LG can be involved in the pathogenic processes of cGVHD-induced dry eye disease.
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31
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Hatakeyama H, Kanzaki M. Heterotypic endosomal fusion as an initial trigger for insulin-induced glucose transporter 4 (GLUT4) translocation in skeletal muscle. J Physiol 2017; 595:5603-5621. [PMID: 28556933 DOI: 10.1113/jp273985] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 05/26/2017] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Comprehensive imaging analyses of glucose transporter 4 (GLUT4) behaviour in mouse skeletal muscle was conducted. Quantum dot-based single molecule nanometry revealed that GLUT4 molecules in skeletal myofibres are governed by regulatory systems involving 'static retention' and 'stimulus-dependent liberation'. Vital imaging analyses and super-resolution microscopy-based morphometry demonstrated that insulin liberates the GLUT4 molecule from its static state by triggering acute heterotypic endomembrane fusion arising from the very small GLUT4-containing vesicles in skeletal myofibres. Prior exposure to exercise-mimetic stimuli potentiated this insulin-responsive endomembrane fusion event involving GLUT4-containing vesicles, suggesting that this endomembranous regulation process is a potential site related to the effects of exercise. ABSTRACT Skeletal muscle is the major systemic glucose disposal site. Both insulin and exercise facilitate translocation of the glucose transporter glucose transporter 4 (GLUT4) via distinct signalling pathways and exercise also enhances insulin sensitivity. However, the trafficking mechanisms controlling GLUT4 mobilization in skeletal muscle remain poorly understood as a resuly of technical limitations. In the present study, which employs various imaging techniques on isolated skeletal myofibres, we show that one of the initial triggers of insulin-induced GLUT4 translocation is heterotypic endomembrane fusion arising from very small static GLUT4-containing vesicles with a subset of transferrin receptor-containing endosomes. Importantly, pretreatment with exercise-mimetic stimuli potentiated the susceptibility to insulin responsiveness, as indicated by these acute endomembranous activities. We also found that AS160 exhibited stripe-like localization close to sarcomeric α-actinin and that insulin induced a reduction of the stripe-like localization accompanying changes in its detergent solubility. The results of the present study thus provide a conceptual framework indicating that GLUT4 protein trafficking via heterotypic fusion is a critical feature of GLUT4 translocation in skeletal muscles and also suggest that the efficacy of the endomembranous fusion process in response to insulin is involved in the benefits of exercise.
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Affiliation(s)
- Hiroyasu Hatakeyama
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan.,Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
| | - Makoto Kanzaki
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
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Stevenson NL, White IJ, McCormack JJ, Robinson C, Cutler DF, Nightingale TD. Clathrin-mediated post-fusion membrane retrieval influences the exocytic mode of endothelial Weibel-Palade bodies. J Cell Sci 2017; 130:2591-2605. [PMID: 28674075 PMCID: PMC5558267 DOI: 10.1242/jcs.200840] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 06/10/2017] [Indexed: 01/15/2023] Open
Abstract
Weibel-Palade bodies (WPBs), the storage organelles of endothelial cells, are essential to normal haemostatic and inflammatory responses. Their major constituent protein is von Willebrand factor (VWF) which, following stimulation with secretagogues, is released into the blood vessel lumen as large platelet-catching strings. This exocytosis changes the protein composition of the cell surface and also results in a net increase in the amount of plasma membrane. Compensatory endocytosis is thought to limit changes in cell size and retrieve fusion machinery and other misplaced integral membrane proteins following exocytosis; however, little is known about the extent, timing, mechanism and precise function of compensatory endocytosis in endothelial cells. Using biochemical assays, live-cell imaging and correlative spinning-disk microscopy and transmission electron microscopy assays we provide the first in-depth high-resolution characterisation of this process. We provide a model of compensatory endocytosis based on rapid clathrin- and dynamin-mediated retrieval. Inhibition of this process results in a change of exocytic mode: WPBs then fuse with previously fused WPBs rather than the plasma membrane, leading, in turn, to the formation of structurally impaired tangled VWF strings. This article has an associated First Person interview with the first authors of the paper. Summary: Compensatory endocytosis plays key roles in Weibel-Palade body exocytosis. Inhibition of this process results in a change of exocytic mode and the release of von Willebrand factor as tangled strings.
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Affiliation(s)
- Nicola L Stevenson
- MRC Cell Biology Unit, Laboratory of Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Ian J White
- MRC Cell Biology Unit, Laboratory of Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Jessica J McCormack
- MRC Cell Biology Unit, Laboratory of Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Christopher Robinson
- Centre for Microvascular Research, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Daniel F Cutler
- MRC Cell Biology Unit, Laboratory of Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Thomas D Nightingale
- Centre for Microvascular Research, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
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33
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Woo SS, James DJ, Martin TFJ. Munc13-4 functions as a Ca 2+ sensor for homotypic secretory granule fusion to generate endosomal exocytic vacuoles. Mol Biol Cell 2017; 28:792-808. [PMID: 28100639 PMCID: PMC5349786 DOI: 10.1091/mbc.e16-08-0617] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 01/06/2017] [Accepted: 01/11/2017] [Indexed: 12/22/2022] Open
Abstract
Munc13-4 is a Ca2+-dependent SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor)- and phospholipid-binding protein that localizes to and primes secretory granules (SGs) for Ca2+-evoked secretion in various secretory cells. Studies in mast cell-like RBL-2H3 cells provide direct evidence that Munc13-4 with its two Ca2+-binding C2 domains functions as a Ca2+ sensor for SG exocytosis. Unexpectedly, Ca2+ stimulation also generated large (>2.4 μm in diameter) Munc13-4+/Rab7+/Rab11+ endosomal vacuoles. Vacuole generation involved the homotypic fusion of Munc13-4+/Rab7+ SGs, followed by a merge with Rab11+ endosomes, and depended on Ca2+ binding to Munc13-4. Munc13-4 promoted the Ca2+-stimulated fusion of VAMP8-containing liposomes with liposomes containing exocytic or endosomal Q-SNAREs and directly interacted with late endosomal SNARE complexes. Thus Munc13-4 is a tethering/priming factor and Ca2+ sensor for both heterotypic SG-plasma membrane and homotypic SG-SG fusion. Total internal reflection fluorescence microscopy imaging revealed that vacuoles were exocytic and mediated secretion of β-hexosaminidase and cytokines accompanied by Munc13-4 diffusion onto the plasma membrane. The results provide new molecular insights into the mechanism of multigranular compound exocytosis commonly observed in various secretory cells.
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Affiliation(s)
- Sang Su Woo
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Declan J James
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Thomas F J Martin
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
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34
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Chen CH, Lo RW, Urban D, Pluthero FG, Kahr WHA. α-granule biogenesis: from disease to discovery. Platelets 2017; 28:147-154. [DOI: 10.1080/09537104.2017.1280599] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Chang Hua Chen
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Richard W. Lo
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Denisa Urban
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Fred G. Pluthero
- Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, ON, Canada
| | - Walter H. A. Kahr
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
- Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, ON, Canada
- Division of Haematology/Oncology, Department of Paediatrics, University of Toronto and The Hospital for Sick Children, Toronto, ON, Canada
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35
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Kunii M, Ohara-Imaizumi M, Takahashi N, Kobayashi M, Kawakami R, Kondoh Y, Shimizu T, Simizu S, Lin B, Nunomura K, Aoyagi K, Ohno M, Ohmuraya M, Sato T, Yoshimura SI, Sato K, Harada R, Kim YJ, Osada H, Nemoto T, Kasai H, Kitamura T, Nagamatsu S, Harada A. Opposing roles for SNAP23 in secretion in exocrine and endocrine pancreatic cells. J Cell Biol 2016; 215:121-138. [PMID: 27697926 PMCID: PMC5057288 DOI: 10.1083/jcb.201604030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 08/26/2016] [Indexed: 12/17/2022] Open
Abstract
Kunii et al. reveal that the SNARE protein SNAP23 plays distinct roles in the secretion of amylase in exocrine cells and of insulin in endocrine cells the pancreas and show that MF286, a novel inhibitor of SNAP23, may be a new drug candidate for diabetes. The membrane fusion of secretory granules with plasma membranes is crucial for the exocytosis of hormones and enzymes. Secretion disorders can cause various diseases such as diabetes or pancreatitis. Synaptosomal-associated protein 23 (SNAP23), a soluble N-ethyl-maleimide sensitive fusion protein attachment protein receptor (SNARE) molecule, is essential for secretory granule fusion in several cell lines. However, the in vivo functions of SNAP23 in endocrine and exocrine tissues remain unclear. In this study, we show opposing roles for SNAP23 in secretion in pancreatic exocrine and endocrine cells. The loss of SNAP23 in the exocrine and endocrine pancreas resulted in decreased and increased fusion of granules to the plasma membrane after stimulation, respectively. Furthermore, we identified a low molecular weight compound, MF286, that binds specifically to SNAP23 and promotes insulin secretion in mice. Our results demonstrate opposing roles for SNAP23 in the secretion mechanisms of the endocrine and exocrine pancreas and reveal that the SNAP23-binding compound MF286 may be a promising drug for diabetes treatment.
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Affiliation(s)
- Masataka Kunii
- Laboratory of Molecular Traffic, Department of Molecular and Cellular Biology, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan Department of Cell Biology, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
| | - Mica Ohara-Imaizumi
- Department of Biochemistry, Kyorin University School of Medicine, Tokyo 181-8611, Japan
| | - Noriko Takahashi
- Laboratory of Structural Physiology, Graduate School of Medicine, Center for Disease Biology and Integrative Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Masaki Kobayashi
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
| | - Ryosuke Kawakami
- Laboratory of Molecular and Cellular Biophysics, Research Institute for Electronic Science, Hokkaido University, Hokkaido 001-0020, Japan
| | - Yasumitsu Kondoh
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Saitama 351-0198, Japan
| | - Takeshi Shimizu
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Saitama 351-0198, Japan
| | - Siro Simizu
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Kanagawa 223-8522, Japan
| | - Bangzhong Lin
- Drug Discovery Team, Office for University-Industry Collaboration Planning and Promotion, Osaka University, Osaka 565-0871, Japan
| | - Kazuto Nunomura
- Drug Discovery Team, Office for University-Industry Collaboration Planning and Promotion, Osaka University, Osaka 565-0871, Japan
| | - Kyota Aoyagi
- Department of Biochemistry, Kyorin University School of Medicine, Tokyo 181-8611, Japan
| | - Mitsuyo Ohno
- Laboratory of Structural Physiology, Graduate School of Medicine, Center for Disease Biology and Integrative Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Masaki Ohmuraya
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811, Japan
| | - Takashi Sato
- Laboratory of Molecular Traffic, Department of Molecular and Cellular Biology, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
| | - Shin-Ichiro Yoshimura
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
| | - Ken Sato
- Laboratory of Molecular Traffic, Department of Molecular and Cellular Biology, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
| | - Reiko Harada
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan Department of Judo Therapy, Takarazuka University of Medical and Health Care, Hyogo 666-0152, Japan
| | - Yoon-Jeong Kim
- Drug Discovery Team, Office for University-Industry Collaboration Planning and Promotion, Osaka University, Osaka 565-0871, Japan
| | - Hiroyuki Osada
- Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Saitama 351-0198, Japan
| | - Tomomi Nemoto
- Laboratory of Molecular and Cellular Biophysics, Research Institute for Electronic Science, Hokkaido University, Hokkaido 001-0020, Japan
| | - Haruo Kasai
- Laboratory of Structural Physiology, Graduate School of Medicine, Center for Disease Biology and Integrative Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Tadahiro Kitamura
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan
| | - Shinya Nagamatsu
- Department of Biochemistry, Kyorin University School of Medicine, Tokyo 181-8611, Japan
| | - Akihiro Harada
- Laboratory of Molecular Traffic, Department of Molecular and Cellular Biology, Institute for Molecular and Cellular Regulation, Gunma University, Gunma 371-8512, Japan Department of Cell Biology, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
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Respective contributions of single and compound granule fusion to secretion by activated platelets. Blood 2016; 128:2538-2549. [PMID: 27625359 DOI: 10.1182/blood-2016-03-705681] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 09/09/2016] [Indexed: 12/25/2022] Open
Abstract
Although granule secretion is pivotal in many platelet responses, the fusion routes of α and δ granule release remain uncertain. We used a 3D reconstruction approach based on electron microscopy to visualize the spatial organization of granules in unstimulated and activated platelets. Two modes of exocytosis were identified: a single mode that leads to release of the contents of individual granules and a compound mode that leads to the formation of granule-to-granule fusion, resulting in the formation of large multigranular compartments. Both modes occur during the course of platelet secretion. Single fusion events are more visible at lower levels of stimulation and early time points, whereas large multigranular compartments are present at higher levels of agonist and at later time points. Although α granules released their contents through both modes of exocytosis, δ granules underwent only single exocytosis. To define the underlying molecular mechanisms, we examined platelets from vesicle-associated membrane protein 8 (VAMP8) null mice. After weak stimulation, compound exocytosis was abolished and single exocytosis decreased in VAMP8 null platelets. Higher concentrations of thrombin bypassed the VAMP8 requirement, indicating that this isoform is a key but not a required factor for single and/or compound exocytosis. Concerning the biological relevance of our findings, compound exocytosis was observed in thrombi formed after severe laser injury of the vessel wall with thrombin generation. After superficial injury without thrombin generation, no multigranular compartments were detected. Our studies suggest that platelets use both modes of membrane fusion to control the extent of agonist-induced exocytosis.
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Hoang Do O, Thorn P. Insulin secretion from beta cells within intact islets: location matters. Clin Exp Pharmacol Physiol 2015; 42:406-14. [PMID: 25676261 PMCID: PMC4418378 DOI: 10.1111/1440-1681.12368] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 12/21/2014] [Accepted: 01/06/2015] [Indexed: 12/17/2022]
Abstract
The control of hormone secretion is central to body homeostasis, and its dysfunction is important in many diseases. The key cellular steps that lead to hormone secretion have been identified, and the stimulus-secretion pathway is understood in outline for many endocrine cells. In the case of insulin secretion from pancreatic beta cells, this pathway involves the uptake of glucose, cell depolarization, calcium entry, and the triggering of the fusion of insulin-containing granules with the cell membrane. The wealth of information on the control of insulin secretion has largely been obtained from isolated single-cell studies. However, physiologically, beta cells exist within the islets of Langerhans, with structural and functional specializations that are not preserved in single-cell cultures. This review focuses on recent work that is revealing distinct aspects of insulin secretion from beta cells within the islet.
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Affiliation(s)
- Oanh Hoang Do
- School of Biomedical Sciences, University of Queensland, St Lucia, Brisbane, Qld, Australia
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Zhou P, Zhang S, Chen H, Chen Y, Liu X, Sun B. No association of VAMP8 gene polymorphisms with glioma in a Chinese Han population. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:5681-5687. [PMID: 26191281 PMCID: PMC4503152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 04/15/2015] [Indexed: 06/04/2023]
Abstract
Vesicle-associated membrane protein 8 (VAMP8) gene plays an important role in biological functions like endosomal fusion, sequential granule-to-granule fusion and autophagy. The current research identified VAMP8 acted as a novel oncogene by promoting cell proliferation and therapeutic resistance in glioma. Nevertheless, the association between VAMP8 genes polymorphism and glioma patients has not been well studied. In our study, to explore the association between single nucleotide polymorphisms (SNPs) of VAMP8 gene with glioma risk in the Chinese Han population, we performed a hospital based case-control study (992 cases and 1008 controls). Eight common tagging SNPs of VAMP8 gene were genotyped, while no significant difference in allele or genotype frequency was found between glioma patients and healthy controls. No positive linkage disequilibrium (LD) was detected either. No haplotype distribution was positive. Accordingly, our study suggested that VAMP8 gene variants might not contribute to glioma susceptibility and associated with glioma in the Chinese Han population.
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Affiliation(s)
- Ping Zhou
- Department of Neurosurgery, Shanghai Neurosurgical Center, Huashan Hospital, Fudan UniversityShanghai, China
| | - Shuo Zhang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes for Biomedical Sciences, Fudan UniversityShanghai, PR China
| | - Hongyan Chen
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes for Biomedical Sciences, Fudan UniversityShanghai, PR China
| | - Yuanyuan Chen
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes for Biomedical Sciences, Fudan UniversityShanghai, PR China
| | - Xiaodong Liu
- Department of Neurosurgery, Shanghai Neurosurgical Center, Huashan Hospital, Fudan UniversityShanghai, China
| | - Bing Sun
- Department of Neurosurgery, Shanghai Neurosurgical Center, Huashan Hospital, Fudan UniversityShanghai, China
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Stegeman S, Amankwah E, Klein K, O'Mara TA, Kim D, Lin HY, Permuth-Wey J, Sellers TA, Srinivasan S, Eeles R, Easton D, Kote-Jarai Z, Amin Al Olama A, Benlloch S, Muir K, Giles GG, Wiklund F, Gronberg H, Haiman CA, Schleutker J, Nordestgaard BG, Travis RC, Neal D, Pharoah P, Khaw KT, Stanford JL, Blot WJ, Thibodeau S, Maier C, Kibel AS, Cybulski C, Cannon-Albright L, Brenner H, Kaneva R, Teixeira MR, Spurdle AB, Clements JA, Park JY, Batra J. A Large-Scale Analysis of Genetic Variants within Putative miRNA Binding Sites in Prostate Cancer. Cancer Discov 2015; 5:368-79. [PMID: 25691096 PMCID: PMC4390388 DOI: 10.1158/2159-8290.cd-14-1057] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 02/02/2015] [Indexed: 02/02/2023]
Abstract
UNLABELLED Prostate cancer is the second most common malignancy among men worldwide. Genome-wide association studies have identified 100 risk variants for prostate cancer, which can explain approximately 33% of the familial risk of the disease. We hypothesized that a comprehensive analysis of genetic variations found within the 3' untranslated region of genes predicted to affect miRNA binding (miRSNP) can identify additional prostate cancer risk variants. We investigated the association between 2,169 miRSNPs and prostate cancer risk in a large-scale analysis of 22,301 cases and 22,320 controls of European ancestry from 23 participating studies. Twenty-two miRSNPs were associated (P<2.3×10(-5)) with risk of prostate cancer, 10 of which were within 7 genes previously not mapped by GWAS studies. Further, using miRNA mimics and reporter gene assays, we showed that miR-3162-5p has specific affinity for the KLK3 rs1058205 miRSNP T-allele, whereas miR-370 has greater affinity for the VAMP8 rs1010 miRSNP A-allele, validating their functional role. SIGNIFICANCE Findings from this large association study suggest that a focus on miRSNPs, including functional evaluation, can identify candidate risk loci below currently accepted statistical levels of genome-wide significance. Studies of miRNAs and their interactions with SNPs could provide further insights into the mechanisms of prostate cancer risk.
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Affiliation(s)
- Shane Stegeman
- Australian Prostate Cancer Research Centre-Qld, Institute of Health and Biomedical Innovation and School of Biomedical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, Australia
| | - Ernest Amankwah
- Department of Cancer Epidemiology, Moffitt Cancer Center, Tampa, Florida
| | - Kerenaftali Klein
- Statistics Unit, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Tracy A O'Mara
- Molecular Cancer Epidemiology Laboratory, Genetics and Computational Biology Division, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Donghwa Kim
- Department of Molecular Oncology, Moffitt Cancer Center, Tampa, Florida
| | - Hui-Yi Lin
- Department of Biostatistics and Bioinformatics, Moffitt Cancer Center, Tampa, Florida
| | | | - Thomas A Sellers
- Department of Cancer Epidemiology, Moffitt Cancer Center, Tampa, Florida
| | - Srilakshmi Srinivasan
- Australian Prostate Cancer Research Centre-Qld, Institute of Health and Biomedical Innovation and School of Biomedical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, Australia
| | - Rosalind Eeles
- The Institute of Cancer Research, London, United Kingdom. Royal Marsden NHS Foundation Trust, Fulham and Sutton, London and Surrey, United Kingdom
| | - Doug Easton
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Strangeways Laboratory, Cambridge, United Kingdom
| | | | - Ali Amin Al Olama
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Strangeways Laboratory, Cambridge, United Kingdom
| | - Sara Benlloch
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Strangeways Laboratory, Cambridge, United Kingdom
| | | | - Graham G Giles
- Cancer Epidemiology Centre, Cancer Council Victoria, Melbourne, Victoria, Australia. Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Victoria, Australia
| | - Fredrik Wiklund
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
| | - Henrik Gronberg
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
| | - Christopher A Haiman
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California/Norris Comprehensive Cancer Center, Los Angeles, California
| | - Johanna Schleutker
- Department of Medical Biochemistry and Genetics, University of Turku, Turku, Finland. Institute of Biomedical Technology/BioMediTech, University of Tampere and FimLab Laboratories, Tampere, Finland
| | - Børge G Nordestgaard
- Department of Clinical Biochemistry, Herlev Hospital, Copenhagen University Hospital, Herlev, Denmark
| | - Ruth C Travis
- Cancer Epidemiology Unit, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - David Neal
- Surgical Oncology (Uro-Oncology: S4), University of Cambridge, Addenbrooke's Hospital, Cambridge; Cancer Research UK, Cambridge Research Institute, Cambridge, United Kingdom
| | - Paul Pharoah
- Centre for Cancer Genetic Epidemiology, Department of Oncology, University of Cambridge, Strangeways Laboratory, Cambridge, United Kingdom
| | - Kay-Tee Khaw
- Cambridge Institute of Public Health, University of Cambridge, Cambridge, United Kingdom
| | - Janet L Stanford
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington. Department of Epidemiology, School of Public Health, University of Washington, Seattle, Washington
| | - William J Blot
- International Epidemiology Institute, Rockville, Maryland
| | | | - Christiane Maier
- Department of Urology, University Hospital Ulm, Ulm, Germany. Institute of Human Genetics, University Hospital Ulm, Ulm, Germany
| | - Adam S Kibel
- Brigham and Women's Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts. Washington University, St. Louis, Missouri
| | - Cezary Cybulski
- International Hereditary Cancer Center, Department of Genetics and Pathology, Pomeranian Medical University, Szczecin, Poland
| | - Lisa Cannon-Albright
- Division of Genetic Epidemiology, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah
| | - Hermann Brenner
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, Heidelberg, Germany. German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Radka Kaneva
- Molecular Medicine Center and Department of Medical Chemistry and Biochemistry, Medical University-Sofia, Sofia, Bulgaria
| | - Manuel R Teixeira
- Department of Genetics, Portuguese Oncology Institute, Porto; Biomedical Sciences Institute (ICBAS), Porto University, Porto, Portugal
| | - Amanda B Spurdle
- Molecular Cancer Epidemiology Laboratory, Genetics and Computational Biology Division, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Judith A Clements
- Australian Prostate Cancer Research Centre-Qld, Institute of Health and Biomedical Innovation and School of Biomedical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, Australia
| | - Jong Y Park
- Department of Cancer Epidemiology, Moffitt Cancer Center, Tampa, Florida
| | - Jyotsna Batra
- Australian Prostate Cancer Research Centre-Qld, Institute of Health and Biomedical Innovation and School of Biomedical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, Australia.
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Chen Y, Meng D, Wang H, Sun R, Wang D, Wang S, Fan J, Zhao Y, Wang J, Yang S, Huai C, Song X, Qin R, Xu T, Yun D, Hu L, Yang J, Zhang X, Chen H, Chen J, Chen H, Lu D. VAMP8 facilitates cellular proliferation and temozolomide resistance in human glioma cells. Neuro Oncol 2014; 17:407-18. [PMID: 25209430 DOI: 10.1093/neuonc/nou219] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 07/20/2014] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Malignant glioma is a common and lethal primary brain tumor in adults. Here we identified a novel oncoprotein, vesicle-associated membrane protein 8 (VAMP8), and investigated its roles in tumorigenisis and chemoresistance in glioma. METHODS The expression of gene and protein were determined by quantitative PCR and Western blot, respectively. Histological analysis of 282 glioma samples and 12 normal controls was performed by Pearson's chi-squared test. Survival analysis was performed using the log-rank test and Cox proportional hazards regression. Cell proliferation and cytotoxicity assay were conducted using Cell Counting Kit-8. Autophagy was detected by confocal microscopy and Western blot. RESULTS VAMP8 was significantly overexpressed in human glioma specimens and could become a potential novel prognostic and treatment-predictive marker for glioma patients. Overexpression of VAMP8 promoted cell proliferation in vitro and in vivo, whereas knockdown of VAMP8 attenuated glioma growth by arresting cell cycle in the G0/G1 phase. Moreover, VAMP8 contributed to temozolomide (TMZ) resistance by elevating the expression levels of autophagy proteins and the number of autophagosomes. Further inhibition of autophagy via siRNA-mediated knockdown of autophagy-related gene 5 (ATG5) or syntaxin 17 (STX17) reversed TMZ resistance in VAMP8-overexpressing cells, while silencing of VAMP8 impaired the autophagic flux and alleviated TMZ resistance in glioma cells. CONCLUSION Our findings identified VAMP8 as a novel oncogene by promoting cell proliferation and therapeutic resistance in glioma. Targeting VAMP8 may serve as a potential therapeutic regimen for the treatment of glioma.
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Affiliation(s)
- Yuanyuan Chen
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Delong Meng
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Huibo Wang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Ruochuan Sun
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Dongrui Wang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Shuai Wang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Jiajun Fan
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Yingjie Zhao
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Jingkun Wang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Song Yang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Cong Huai
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Xiao Song
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Rong Qin
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Tao Xu
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Dapeng Yun
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Lingna Hu
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Jingmin Yang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Xiaotian Zhang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Haoming Chen
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Juxiang Chen
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Hongyan Chen
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
| | - Daru Lu
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Shanghai, China (Y.C., D.M., D.W., Y.Z., J.W., C.H., X.S., D.Y., L.H., J.Y., H.C., H.C., D.L.); Department of Biosynthesis, School of Pharmacy, Fudan University, Shanghai, China (J.F.); Department of Neurosurgery, (H.W.); Department of Hematology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China (S.W.); Eighth Department of General Surgery and Department of Pathology, First Affiliated Hospital of Anhui Medical University, Hefei, China (R.S., S.Y.); Department of Molecular Human Genetics, Baylor College of Medicine, Houston, Texas (X.Z.); Neurosurgery Research Institution of Shanghai, Department of Neurosurgery, Changzheng Hospital, Second Military Medical University, Shanghai, China (R.Q., T.X., J.C.)
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Messenger SW, Falkowski MA, Thomas DDH, Jones EK, Hong W, Gaisano HY, Giasano HY, Boulis NM, Groblewski GE. Vesicle associated membrane protein 8 (VAMP8)-mediated zymogen granule exocytosis is dependent on endosomal trafficking via the constitutive-like secretory pathway. J Biol Chem 2014; 289:28040-53. [PMID: 25138214 DOI: 10.1074/jbc.m114.593913] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Acinar cell zymogen granules (ZG) express 2 isoforms of the vesicle-associated membrane protein family (VAMP2 and -8) thought to regulate exocytosis. Expression of tetanus toxin to cleave VAMP2 in VAMP8 knock-out (-/-) acini confirmed that VAMP2 and -8 are the primary VAMPs for regulated exocytosis, each contributing ∼50% of the response. Analysis of VAMP8(-/-) acini indicated that although stimulated secretion was significantly reduced, a compensatory increase in constitutive secretion maintained total secretion equivalent to wild type (WT). Using a perifusion system to follow secretion over time revealed VAMP2 mediates an early rapid phase peaking and falling within 2-3 min, whereas VAMP8 controls a second prolonged phase that peaks at 4 min and slowly declines over 20 min to support the protracted secretory response. VAMP8(-/-) acini show increased expression of the endosomal proteins Ti-VAMP7 (2-fold) and Rab11a (4-fold) and their redistribution from endosomes to ZGs. Expression of GDP-trapped Rab11a-S25N inhibited secretion exclusively from the VAMP8 but not the VAMP2 pathway. VAMP8(-/-) acini also showed a >90% decrease in the early endosomal proteins Rab5/D52/EEA1, which control anterograde trafficking in the constitutive-like secretory pathway. In WT acini, short term (14-16 h) culture also results in a >90% decrease in Rab5/D52/EEA1 and a complete loss of the VAMP8 pathway, whereas VAMP2-secretion remains intact. Remarkably, rescue of Rab5/D52/EEA1 expression restored the VAMP8 pathway. Expressed D52 shows extensive colocalization with Rab11a and VAMP8 and partially copurifies with ZG fractions. These results indicate that robust trafficking within the constitutive-like secretory pathway is required for VAMP8- but not VAMP2-mediated ZG exocytosis.
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Affiliation(s)
- Scott W Messenger
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706
| | - Michelle A Falkowski
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706
| | - Diana D H Thomas
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706
| | - Elaina K Jones
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706
| | - Wanjin Hong
- Institute of Molecular and Cellular Biology, National University of Singapore, Singapore 138673
| | | | - Herbert Y Giasano
- Departments of Medicine and Physiology, University of Toronto, Ontario M5S 1A8, Canada, and
| | - Nicholas M Boulis
- Department of Neurosurgery, Georgia Institute of Technology, Atlanta, Georgia 30322
| | - Guy E Groblewski
- From the Department of Nutritional Sciences, University of Wisconsin, Madison, Wisconsin 53706,
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Low JT, Zavortink M, Mitchell JM, Gan WJ, Do OH, Schwiening CJ, Gaisano HY, Thorn P. Insulin secretion from beta cells in intact mouse islets is targeted towards the vasculature. Diabetologia 2014; 57:1655-63. [PMID: 24795086 PMCID: PMC4079948 DOI: 10.1007/s00125-014-3252-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 04/03/2014] [Indexed: 12/28/2022]
Abstract
AIMS/HYPOTHESIS We set out to test the hypothesis that insulin secretion from beta cells is targeted towards the vasculature. METHODS The spatial location of granule fusion was identified by live-cell two-photon imaging of mouse pancreatic beta cells within intact islets, using sulforhodamine B labelling. Three-dimensional (3D) immunofluorescence of pancreatic slices was used to identify the location of proteins associated with neuronal synapses. RESULTS We demonstrated an asymmetric, non-random, distribution of sites of insulin granule fusion in response to glucose and focal targeting of insulin granule secretion to the beta cell membrane facing the vasculature. 3D immunofluorescence of islets showed that structural proteins, such as liprin, piccolo and Rab2-interacting molecule, normally associated with neuronal presynaptic targeting, were present in beta cells and enriched at the vascular face. In contrast, we found that syntaxin 1A and synaptosomal-associated protein 25 kDa (SNAP25) were relatively evenly distributed across the beta cells. CONCLUSIONS/INTERPRETATION Our results show that beta cells in situ, within intact islets, are polarised and target insulin secretion. This evidence for an 'endocrine synapse' has wide implications for our understanding of stimulus-secretion coupling in healthy islets and in disease.
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Affiliation(s)
- Jiun T Low
- School of Biomedical Sciences, University of Queensland, St Lucia, QLD, 4072, Australia
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Do OH, Low JT, Gaisano HY, Thorn P. The secretory deficit in islets from db/db mice is mainly due to a loss of responding beta cells. Diabetologia 2014; 57:1400-9. [PMID: 24705605 PMCID: PMC4052007 DOI: 10.1007/s00125-014-3226-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 03/07/2014] [Indexed: 12/03/2022]
Abstract
AIMS/HYPOTHESIS We used the db/db mouse to determine the nature of the secretory defect in intact islets. METHODS Glucose tolerance was compared in db/db and wild-type (WT) mice. Isolated islets were used: to measure insulin secretion and calcium in a two-photon assay of single-insulin-granule fusion; and for immunofluorescence of soluble N-ethylmaleimide-sensitive factor attachment proteins (SNAREs). RESULTS The 13-18-week-old db/db mice showed a diabetic phenotype. Isolated db/db islets showed a 77% reduction in insulin secretion induced by 15 mmol/l glucose and reductions in the amplitude and rise-time of the calcium response to glucose. Ionomycin-induced insulin secretion in WT but not db/db islets. Immunofluorescence showed an increase in the levels of the SNAREs synaptosomal-associated protein 25 (SNAP25) and vesicle-associated membrane protein 2 (VAMP2) in db/db islets, but reduced syntaxin-1A. Therefore, db/db islets have both a compromised calcium response to glucose and a compromised secretory response to calcium. Two-photon microscopy of isolated islets determined the number and distribution of insulin granule exocytic events. Compared with WT, db/db islets showed far fewer exocytic events (an 83% decline at 15 mmol/l glucose). This decline was due to a 73% loss of responding cells and, in the remaining responsive cells, a 50% loss of exocytic responses per cell. An assay measuring granule re-acidification showed evidence for more recaptured granules in db/db islets compared with WT. CONCLUSIONS/INTERPRETATION We showed that db/db islets had a reduced calcium response to glucose and a reduction in syntaxin-1A. Within the db/db islets, changes were manifest as both a reduction in responding cells and a reduction in fusing insulin granules per cell.
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Affiliation(s)
- Oanh H. Do
- School of Biomedical Sciences, University of Queensland, St Lucia, QLD 4072 Australia
| | - Jiun T. Low
- School of Biomedical Sciences, University of Queensland, St Lucia, QLD 4072 Australia
| | | | - Peter Thorn
- School of Biomedical Sciences, University of Queensland, St Lucia, QLD 4072 Australia
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Abstract
Little is known about the molecular mechanism mediating renin granule exocytosis and the identity of proteins involved. We previously showed that soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNAREs), a family of proteins required for exocytosis, mediate the stimulated release of renin from juxtaglomerular cells. This minireview focuses on the current knowledge of the proteins that facilitate renin-granule exocytosis. We discuss the identity of potential candidates that mediate the signaling and final steps of exocytosis of the renin granule.
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Affiliation(s)
- Mariela Mendez
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, Detroit, Michigan
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Azouz NP, Zur N, Efergan A, Ohbayashi N, Fukuda M, Amihai D, Hammel I, Rothenberg ME, Sagi-Eisenberg R. Rab5 Is a Novel Regulator of Mast Cell Secretory Granules: Impact on Size, Cargo, and Exocytosis. THE JOURNAL OF IMMUNOLOGY 2014; 192:4043-53. [DOI: 10.4049/jimmunol.1302196] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Messenger SW, Falkowski MA, Groblewski GE. Ca²⁺-regulated secretory granule exocytosis in pancreatic and parotid acinar cells. Cell Calcium 2014; 55:369-75. [PMID: 24742357 DOI: 10.1016/j.ceca.2014.03.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 03/04/2014] [Accepted: 03/09/2014] [Indexed: 01/09/2023]
Abstract
Protein secretion from acinar cells of the pancreas and parotid glands is controlled by G-protein coupled receptor activation and generation of the cellular messengers Ca(2+), diacylglycerol and cAMP. Secretory granule (SG) exocytosis shares some common characteristics with nerve, neuroendocrine and endocrine cells which are regulated mainly by elevated cell Ca(2+). However, in addition to diverse signaling pathways, acinar cells have large ∼1 μm diameter SGs (∼30 fold larger diameter than synaptic vesicles), respond to stimulation at slower rates (seconds versus milliseconds), demonstrate significant constitutive secretion, and in isolated acini, undergo sequential compound SG-SG exocytosis at the apical membrane. Exocytosis proceeds as an initial rapid phase that peaks and declines over 3 min followed by a prolonged phase that decays to near basal levels over 20-30 min. Studies indicate the early phase is triggered by Ca(2+) and involves the SG proteins VAMP2 (vesicle associated membrane protein2), Ca(2+)-sensing protein synatotagmin 1 (syt1) and the accessory protein complexin 2. The molecular details for regulation of VAMP8-mediated SG exocytosis and the prolonged phase of secretion are still emerging. Here we review the known regulatory molecules that impact the sequential exocytic process of SG tethering, docking, priming and fusion in acinar cells.
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Affiliation(s)
- Scott W Messenger
- Department of Nutritional Sciences, Graduate Program in Biochemical and Molecular Nutrition, University of Wisconsin, Madison, WI 53706, United States
| | - Michelle A Falkowski
- Department of Nutritional Sciences, Graduate Program in Biochemical and Molecular Nutrition, University of Wisconsin, Madison, WI 53706, United States
| | - Guy E Groblewski
- Department of Nutritional Sciences, Graduate Program in Biochemical and Molecular Nutrition, University of Wisconsin, Madison, WI 53706, United States.
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Xu R, Li Q, Zhou X, Perelman JM, Kolosov VP. Annexin II mediates the neutrophil elastase-stimulated exocytosis of mucin 5ac. Mol Med Rep 2013; 9:299-304. [PMID: 24247640 DOI: 10.3892/mmr.2013.1795] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2013] [Accepted: 11/06/2013] [Indexed: 11/06/2022] Open
Abstract
The overexpression and hypersecretion of mucus is a hallmark of several chronic pulmonary inflammatory diseases, including chronic obstructive pulmonary disease (COPD), asthma and cystic fibrosis. Mucin 5ac (MUC5AC) is a major component of airway mucus. Annexin II (ANXII) has been reported to be expressed in various cells and is associated with the fusion of secretory vesicles. Neutrophil elastase (NE) is present at high concentrations in the airway surface fluid in patients with cystic fibrosis and various other severe diseases. However, the role of ANXII in NE-induced secretion of MUC5AC granules remains unclear. It was determined that NE upregulates the transcription and protein synthesis of ANXII in 16HBE human bronchial epithelial cells. Following stimulation with NE, ANXII is recruited to the cell membrane, as visualised by cell immunochemistry and laser confocal microscopy, and the redistribution of ANXII is inhibited by the protein kinase-C (PKC) inhibitor bisindolylmaleimide I. Conversely, depleting endogenous ANXII decreases MUC5AC secretion into the cell culture supernatant and increases the levels of intracellular MUC5AC protein. The data indicated that ANXII is associated with the secretion of MUC5AC granules.
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Affiliation(s)
- Rui Xu
- Department of Respiratory Medicine, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010, P.R. China
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Directing exocrine secretory vesicles to the apical membrane by actin cables generated by the formin mDia1. Proc Natl Acad Sci U S A 2013; 110:10652-7. [PMID: 23754409 DOI: 10.1073/pnas.1303796110] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The final stage in exocrine secretion involves translocation of vesicles from their storage areas to the apical membrane. We show that actin-coated secretory vesicles of the exocrine pancreas travel this distance over bundles of specialized actin cables emanating from the apical plasma membrane. These bundles are stable structures that require constant G-actin incorporation and are distinct from the actin web that surrounds the exocrine lumen. The murine mammalian Diaphanous-related formin 1 (mDia1) was identified as a generator of these cables. The active form of mDia1 localized to the apical membrane, and introduction of an active form of mDia1 led to a marked increase in bundle density along the lumen perimeter. Compromising formation of the cables does not prevent secretion, but results in disorganized trafficking and fusion between secretory vesicles. Similar apical secretory tracks were also found in the submandibular salivary glands. Together with previous results that identified a role for Diaphanous in apical secretion in tubular organs of Drosophila, the role of Diaphanous formins at the final stages of secretion appears to be highly conserved.
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Stow JL, Murray RZ. Intracellular trafficking and secretion of inflammatory cytokines. Cytokine Growth Factor Rev 2013; 24:227-39. [PMID: 23647915 DOI: 10.1016/j.cytogfr.2013.04.001] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The secretion of cytokines by immune cells plays a significant role in determining the course of an inflammatory response. The levels and timing of each cytokine released are critical for mounting an effective but confined response, whereas excessive or dysregulated inflammation contributes to many diseases. Cytokines are both culprits and targets for effective treatments in some diseases. The multiple points and mechanisms that have evolved for cellular control of cytokine secretion highlight the potency of these mediators and the fine tuning required to manage inflammation. Cytokine production in cells is regulated by cell signaling, and at mRNA and protein synthesis levels. Thereafter, the intracellular transport pathways and molecular trafficking machinery have intricate and essential roles in dictating the release and activity of cytokines. The trafficking machinery and secretory (exocytic) pathways are complex and highly regulated in many cells, involving specialized membranes, molecules and organelles that enable these cells to deliver cytokines to often-distinct areas of the cell surface, in a timely manner. This review provides an overview of secretory pathways - both conventional and unconventional - and key families of trafficking machinery. The prevailing knowledge about the trafficking and secretion of a number of individual cytokines is also summarized. In conclusion, we present emerging concepts about the functional plasticity of secretory pathways and their modulation for controlling cytokines and inflammation.
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Affiliation(s)
- Jennifer L Stow
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia.
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Pols MS, ten Brink C, Gosavi P, Oorschot V, Klumperman J. The HOPS proteins hVps41 and hVps39 are required for homotypic and heterotypic late endosome fusion. Traffic 2012; 14:219-32. [PMID: 23167963 DOI: 10.1111/tra.12027] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 11/14/2012] [Accepted: 11/21/2012] [Indexed: 12/11/2022]
Abstract
The homotypic fusion and protein sorting (HOPS) complex is a multisubunit tethering complex that in yeast regulates membrane fusion events with the vacuole, the yeast lysosome. Mammalian homologs of all HOPS components have been found, but little is known about their function. Here, we studied the role of hVps41 and hVps39, two components of the putative human HOPS complex, in the endo-lysosomal pathway of human cells. By expressing hemagglutinin (HA)-tagged constructs, we show by immunoelectron microscopy (immunoEM) that both hVps41 and hVps39 associate with the limiting membrane of late endosomes as well as lysosomes. Small interference RNA (siRNA)-mediated knockdown of hVps41 or hVps39 resulted in an accumulation of late endosomes, a depletion in the number of lysosomes and a block in the degradation of endocytosed cargo. Lysosomal pH and cathepsin B activity remained unaltered in these conditions. By immunoEM we found that hVps41 or hVps39 knockdown impairs homotypic fusion between late endosomes as well as heterotypic fusion between late endosomes and lysosomes. Thus, our data show that both hVps41 and hVps39 are required for late endosomal-lysosomal fusion events and the delivery of endocytic cargo to lysosomes in human cells.
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Affiliation(s)
- Maaike S Pols
- Department of Cell Biology, University Medical Center Utrecht, Heidelberglaan 100, 3584, CX Utrecht, The Netherlands
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