1
|
Liu M, Duan Y, Dong J, Zhang K, Jin X, Gao M, Jia H, Chen J, Liu M, Wei M, Zhong X. Early signs of neurodegenerative diseases: Possible mechanisms and targets for Golgi stress. Biomed Pharmacother 2024; 175:116646. [PMID: 38692058 DOI: 10.1016/j.biopha.2024.116646] [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: 02/28/2024] [Revised: 04/17/2024] [Accepted: 04/24/2024] [Indexed: 05/03/2024] Open
Abstract
The Golgi apparatus plays a crucial role in mediating the modification, transport, and sorting of intracellular proteins and lipids. The morphological changes occurring in the Golgi apparatus are exceptionally important for maintaining its function. When exposed to external pressure or environmental stimulation, the Golgi apparatus undergoes adaptive changes in both structure and function, which are known as Golgi stress. Although certain signal pathway responses or post-translational modifications have been observed following Golgi stress, further research is needed to comprehensively summarize and understand the related mechanisms. Currently, there is evidence linking Golgi stress to neurodegenerative diseases; however, the role of Golgi stress in the progression of neurodegenerative diseases such as Alzheimer's disease remains largely unexplored. This review focuses on the structural and functional alterations of the Golgi apparatus during stress, elucidating potential mechanisms underlying the involvement of Golgi stress in regulating immunity, autophagy, and metabolic processes. Additionally, it highlights the pivotal role of Golgi stress as an early signaling event implicated in the pathogenesis and progression of neurodegenerative diseases. Furthermore, this study summarizes prospective targets that can be therapeutically exploited to mitigate neurodegenerative diseases by targeting Golgi stress. These findings provide a theoretical foundation for identifying novel breakthroughs in preventing and treating neurodegenerative diseases.
Collapse
Affiliation(s)
- Mengyu Liu
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China
| | - Ying Duan
- Liaoning Maternal and Child Health Hospital, Shayang, Liaoning 110005, China
| | - Jianru Dong
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China
| | - Kaisong Zhang
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China
| | - Xin Jin
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China
| | - Menglin Gao
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China
| | - Huachao Jia
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China
| | - Ju Chen
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China
| | - Mingyan Liu
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China.
| | - Minjie Wei
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China; Liaoning Medical Diagnosis and Treatment Center, Shenyang, Liaoning 110167, China.
| | - Xin Zhong
- School of Pharmacy, China Medical University, Shenyang, Liaoning 110122, China.
| |
Collapse
|
2
|
Lujan P, Garcia-Cabau C, Wakana Y, Vera Lillo J, Rodilla-Ramírez C, Sugiura H, Malhotra V, Salvatella X, Garcia-Parajo MF, Campelo F. Sorting of secretory proteins at the trans-Golgi network by human TGN46. eLife 2024; 12:RP91708. [PMID: 38466628 DOI: 10.7554/elife.91708] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024] Open
Abstract
Secretory proteins are sorted at the trans-Golgi network (TGN) for export into specific transport carriers. However, the molecular players involved in this fundamental process remain largely elusive. Here, we identified the human transmembrane protein TGN46 as a receptor for the export of secretory cargo protein PAUF in CARTS - a class of protein kinase D-dependent TGN-to-plasma membrane carriers. We show that TGN46 is necessary for cargo sorting and loading into nascent carriers at the TGN. By combining quantitative fluorescence microscopy and mutagenesis approaches, we further discovered that the lumenal domain of TGN46 encodes for its cargo sorting function. In summary, our results define a cellular function of TGN46 in sorting secretory proteins for export from the TGN.
Collapse
Affiliation(s)
- Pablo Lujan
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Carla Garcia-Cabau
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Yuichi Wakana
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Javier Vera Lillo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Carmen Rodilla-Ramírez
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Hideaki Sugiura
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Vivek Malhotra
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Xavier Salvatella
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Maria F Garcia-Parajo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Felix Campelo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| |
Collapse
|
3
|
Ma S, Sa L, Zhang J, Jiang K, Mi B, Shan L. KDELR2 as a diagnostic and prognostic biomarker of bladder urothelial carcinoma and its correlation with immune infiltration. Genet Mol Biol 2023; 46:e20230002. [PMID: 37791813 PMCID: PMC10548500 DOI: 10.1590/1678-4685-gmb-2023-0002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 07/21/2023] [Indexed: 10/05/2023] Open
Abstract
KDELR2 has been reported as a promotive factor for the genesis and progression of several malignancies. However, it is uncertain how it affects bladder urothelial carcinoma (BLCA). Using data extracted from online databases, an enhanced expression of KDELR2 in BLCA tissues was verified. Overexpression of KDELR2 was correlated with advanced clinicopathologic characteristics and unfavourable prognosis of BLCA. Receiver operating characteristic analysis highlighted the potential diagnostic value of KDELR2. Univariate and multivariate logistic regression analyses further revealed the predictive effect of KDELR2 for the prognosis of BLCA. KDELR2 was primarily enriched in biological functions related to organization of the extracellular matrix. TIMER, ssGSEA and GEPIA analyses suggested that KDELR2 expression is positively related to the infiltration of macrophages, Th2 cells and neutrophils. Finally, knocking-down of KDELR2 in T24 cells resulted in reduced proliferation, migration and macrophages recruitment. These results suggest that KDELR2 overexpression is an indicator for poor prognosis of BLCA and it has the potential to be employed as an immunotherapy target for BLCA.
Collapse
Affiliation(s)
- Sai Ma
- Air Force Medical University, School of Stomatology, National Clinical Research Centre for Oral Disease, State Key Laboratory of Military Stomatology, Department of Prosthodontics, Shaanxi Key Laboratory of Stomatology, Xi'an, Shaanxi, China
| | - Longqi Sa
- Xi'an Jiaotong University, Honghui Hospital, Department of Spine Surgery, Xi'an, Shaanxi, China
| | - Jitao Zhang
- Xi'an Jiaotong University, Honghui Hospital, Department of Spine Surgery, Xi'an, Shaanxi, China
| | - Kuo Jiang
- Xi'an Jiaotong University, Honghui Hospital, Department of Spine Surgery, Xi'an, Shaanxi, China
| | - Baoguo Mi
- Xi'an Jiaotong University, Honghui Hospital, Department of Spine Surgery, Xi'an, Shaanxi, China
| | - Lequn Shan
- Xi'an Jiaotong University, Honghui Hospital, Department of Spine Surgery, Xi'an, Shaanxi, China
| |
Collapse
|
4
|
Tan C, Du Y, Zhu L, Jing S, Gao J, Qian Y, Yue X, Lee I. KDEL Receptor Trafficking to the Plasma Membrane Is Regulated by ACBD3 and Rab4A-GTP. Cells 2023; 12:cells12071079. [PMID: 37048152 PMCID: PMC10093020 DOI: 10.3390/cells12071079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/01/2023] [Accepted: 03/14/2023] [Indexed: 04/07/2023] Open
Abstract
KDEL receptor-1 maintains homeostasis in the early secretory pathway by capturing and retrieving ER chaperones to the ER during heavy secretory activity. Unexpectedly, a fraction of the receptor is also known to reside in the plasma membrane (PM), although it is largely unknown exactly how the KDEL receptor gets exported from the Golgi and travels to the PM. We have previously shown that a Golgi scaffolding protein (ACBD3) facilitates KDEL receptor localization at the Golgi via the regulating cargo wave-induced cAMP/PKA-dependent signaling pathway. Upon endocytosis, surface-expressed KDEL receptor undergoes highly complex itineraries through the Golgi and the endo-lysosomal compartments, where the endocytosed receptor utilizes Rab14A- and Rab11A-positive recycling endosomes and clathrin-decorated tubulovesicular carriers. In this study, we sought to investigate the mechanism through which the KDEL receptor gets exported from the Golgi en route to the PM. We report here that ACBD3 depletion results in greatly increased trafficking of KDEL receptor to the PM via Rab4A-positive tubular carriers emanating from the Golgi. Expression of constitutively activated Rab4A mutant (Q72L) increases the surface expression of KDEL receptor up to 2~3-fold, whereas Rab4A knockdown or the expression of GDP-locked Rab4A mutant (S27N) inhibits KDEL receptor targeting of the PM. Importantly, KDELR trafficking from the Golgi to the PM is independent of PKA- and Src kinase-mediated mechanisms. Taken together, these results reveal that ACBD3 and Rab4A play a key role in regulating KDEL receptor trafficking to the cell surface.
Collapse
Affiliation(s)
- Chuanting Tan
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 101408, China
| | - Yulei Du
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 101408, China
| | - Lianhui Zhu
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Shuaiyang Jing
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 101408, China
| | - Jingkai Gao
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 101408, China
| | - Yi Qian
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Xihua Yue
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Intaek Lee
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| |
Collapse
|
5
|
Palazzo FC, Sitia R, Tempio T. Selective Secretion of KDEL-Bearing Proteins: Mechanisms and Functions. Front Cell Dev Biol 2022; 10:967875. [PMID: 35912099 PMCID: PMC9326092 DOI: 10.3389/fcell.2022.967875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 06/24/2022] [Indexed: 11/13/2022] Open
Abstract
In multicellular organisms, cells must continuously exchange messages with the right meaning, intensity, and duration. Most of these messages are delivered through cognate interactions between membrane and secretory proteins. Their conformational maturation is assisted by a vast array of chaperones and enzymes, ensuring the fidelity of intercellular communication. These folding assistants reside in the early secretory compartment (ESC), a functional unit that encompasses endoplasmic reticulum (ER), intermediate compartment and cis-Golgi. Most soluble ESC residents have C-terminal KDEL-like motifs that prevent their transport beyond the Golgi. However, some accumulate in the ER, while others in downstream stations, implying different recycling rates. Moreover, it is now clear that cells can actively secrete certain ESC residents but not others. This essay discusses the physiology of their differential intracellular distribution, and the mechanisms that may ensure selectivity of release.
Collapse
|
6
|
Zhang G, Wang B, Cheng S, Fan H, Liu S, Zhou B, Liu W, Liang R, Tang Y, Zhang Y. KDELR2 knockdown synergizes with temozolomide to induce glioma cell apoptosis through the CHOP and JNK/p38 pathways. Transl Cancer Res 2021; 10:3491-3506. [PMID: 35116653 PMCID: PMC8799170 DOI: 10.21037/tcr-21-869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/23/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND The C-terminal tetrapeptide Lys-Asp-Glu-Leu receptors (KDELRs) are transmembrane proteins that regulate ER stress (ERS) response, growth, differentiation, and immune responses. There is an association between KDELR2and promotion of glioblastoma tumorigenesis. The aim of the present study was to explore the functional mechanism of KDELR2 in glioma and during response to chemotherapy to temozolomide (TMZ). METHODS The expression of KDELR2 in glioma tissues and cells was evaluated by immunohistochemistry, western blot and RT-qPCR assay. Then role of KDELR2 was demonstrated by CCK8, colony formation, flow cytometry and Hochest 33258 assays. The expression of genes (ATF4, ATF6, PERK, eIF2-α, GRP78 and CHOP) in U373 cells was evaluated by RT-qPCR. The protein expression of genes (cleaved caspase 3, caspase 3, cleaved PARP, PARP, Bax, Bcl-2, JNK, p-JNK, p38, p-p38, ATF4, ATF6, XBP-1s, PERK, p-PERK, GRP78 and CHOP) was measured by western blot assay. RESULTS The expression of KDELR2 was upregulated in high-grade gliomas tissues. KDELR2 knockdown suppressed cell proliferation but increased cell apoptosis. Further, Knockdown of KDELR2 also activated the ER stress (ERS)-dependent CHOP pathway, and resulted in increased levels of phosphorylated c-Jun N-terminal kinase (JNK) and p38. Moreover, the combination of KDELR2 knockdown and TMZ application showed a synergistic cytotoxic effect in U373 cells through the ERS-dependent CHOP and JNK/p38 pathways. CONCLUSIONS KDELR2 knockdown induces apoptosis and sensitizes glioma cells to TMZ, which is mediated by the ERS-dependent CHOP and JNK/p38 pathways.
Collapse
Affiliation(s)
- Guofeng Zhang
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
- Department of Neurosurgery, The Affiliated Jiujiang Hospital of Nanchang University, Jiujiang, China
| | - Bin Wang
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Shiqi Cheng
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Hengyi Fan
- Department Radiation Oncology, Klinikum rechts der lsar, Technische Universität München, Munich, Germany
| | - Shaowen Liu
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Bin Zhou
- Department of Pathology, The Affiliated Jiujiang Hospital of Nanchang University, Jiujiang, China
| | - Weibin Liu
- Department of Neurosurgery, The Affiliated Jiujiang Hospital of Nanchang University, Jiujiang, China
| | - Rui Liang
- Department of Neurosurgery, The Affiliated Jiujiang Hospital of Nanchang University, Jiujiang, China
| | - Youjia Tang
- Department of Neurosurgery, The Affiliated Jiujiang Hospital of Nanchang University, Jiujiang, China
| | - Yan Zhang
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| |
Collapse
|
7
|
Zhang H, Chi J, Hu J, Ji T, Luo Z, Zhou C, Huang L, Dai Z, Li J, Wang G, Wang L, Wang Z. Intracellular AGR2 transduces PGE2 stimuli to promote epithelial-mesenchymal transition and metastasis of colorectal cancer. Cancer Lett 2021; 518:180-195. [PMID: 34216690 DOI: 10.1016/j.canlet.2021.06.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 06/02/2021] [Accepted: 06/29/2021] [Indexed: 01/01/2023]
Abstract
Human anterior gradient homolog 2 (AGR2) reportedly acts as an oncogene in multiple types of cancers. As a secreted protein, the oncogenic roles of extracellular AGR2 have been the focus of the increasing number of studies. In contrast, the oncological functions of intracellular AGR2 (iAGR2) remain elusive. Here, we report that intracellular AGR2 (iAGR2) is sufficient to promote CRC metastasis. iAGR2 binds to KDEL receptors (KDELRs) via its KTEL motif to activate downstream Gs-PKA signaling. Activated PKA upregulates the expression of NF-κB subunit c-Rel (REL) and acetylates histone H3 at lysine 9 (H3K9ac) to promote the transcription of SNAIL and SLUG. AGR2 can be upregulated by prostaglandin E2 (PGE2) via EP4-PI3K-AKT pathway and is indispensable for PGE2-induced CRC metastasis. AGR2 knockdown enhances therapeutic effects of a COX-2 inhibitor, celecoxib, in CRC metastasis. Collectively, our study reveals a promoting role and molecular mechanisms of iAGR2 in CRC metastasis and uncovers a new tumor microenvironment signal regulating AGR2 expression, which may provide new targets for treating metastatic CRC.
Collapse
Affiliation(s)
- Hongyan Zhang
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Jiangyang Chi
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Jia Hu
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Tiantian Ji
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Zhen Luo
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Caihong Zhou
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Lifeng Huang
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Zheng Dai
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China; Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Jing Li
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Guobin Wang
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China.
| | - Lin Wang
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China; Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China.
| | - Zheng Wang
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China; Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China.
| |
Collapse
|
8
|
The PKD-Dependent Biogenesis of TGN-to-Plasma Membrane Transport Carriers. Cells 2021; 10:cells10071618. [PMID: 34203456 PMCID: PMC8303525 DOI: 10.3390/cells10071618] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/14/2021] [Accepted: 06/24/2021] [Indexed: 01/30/2023] Open
Abstract
Membrane trafficking is essential for processing and transport of proteins and lipids and to establish cell compartmentation and tissue organization. Cells respond to their needs and control the quantity and quality of protein secretion accordingly. In this review, we focus on a particular membrane trafficking route from the trans-Golgi network (TGN) to the cell surface: protein kinase D (PKD)-dependent pathway for constitutive secretion mediated by carriers of the TGN to the cell surface (CARTS). Recent findings highlight the importance of lipid signaling by organelle membrane contact sites (MCSs) in this pathway. Finally, we discuss our current understanding of multiple signaling pathways for membrane trafficking regulation mediated by PKD, G protein-coupled receptors (GPCRs), growth factors, metabolites, and mechanosensors.
Collapse
|
9
|
Gonzalez-Gronow M, Gopal U, Austin RC, Pizzo SV. Glucose-regulated protein (GRP78) is an important cell surface receptor for viral invasion, cancers, and neurological disorders. IUBMB Life 2021; 73:843-854. [PMID: 33960608 DOI: 10.1002/iub.2502] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/14/2021] [Accepted: 05/01/2021] [Indexed: 12/22/2022]
Abstract
The 78 kDa glucose-regulated protein (GRP78) is an endoplasmic reticulum (ER)-resident molecular chaperone. GRP78 is a member of the 70 kDa heat shock family of proteins involved in correcting and clearing misfolded proteins in the ER. In response to cellular stress, GRP78 escapes from the ER and moves to the plasma membrane where it (a) functions as a receptor for many ligands, and (b) behaves as an autoantigen for autoantibodies that contribute to human disease and cancer. Cell surface GRP78 (csGRP78) associates with the major histocompatibility complex class I (MHC-I), and is the port of entry for several viruses, including the predictive binding of the novel SARS-CoV-2. Furthermore, csGRP78 is found in association with partners as diverse as the teratocarcinoma-derived growth factor 1 (Cripto), the melanocortin-4 receptor (MC4R) and the DnaJ-like protein MTJ-1. CsGRP78 also serves as a receptor for a large variety of ligands including activated α2 -macroglobulin (α2 M*), plasminogen kringle 5 (K5), microplasminogen, the voltage-dependent anion channel (VDAC), tissue factor (TF), and the prostate apoptosis response-4 protein (Par-4). In this review, we discuss the mechanisms involved in the translocation of GRP78 from the ER to the cell surface, and the role of secreted GRP78 and its autoantibodies in cancer and neurological disorders.
Collapse
Affiliation(s)
- Mario Gonzalez-Gronow
- Department of Biological Sciences, Laboratory of Environmental Neurotoxicology, Faculty of Medicine, Universidad Católica del Norte, Coquimbo, Chile.,Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
| | - Udhayakumar Gopal
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
| | - Richard C Austin
- Department of Medicine, Division of Nephrology, McMaster University and The Research Institute of St. Joseph's Hamilton, Hamilton, Ontario, Canada
| | - Salvatore V Pizzo
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
| |
Collapse
|
10
|
The Secreted Protein C10orf118 Is a New Regulator of Hyaluronan Synthesis Involved in Tumour-Stroma Cross-Talk. Cancers (Basel) 2021; 13:cancers13051105. [PMID: 33807583 PMCID: PMC7961460 DOI: 10.3390/cancers13051105] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 02/26/2021] [Indexed: 12/20/2022] Open
Abstract
Simple Summary Hyaluronan is a main glycosaminoglycan in extracellular matrix with an important role in breast cancer progression. Alterations in its synthesis and size may affect tu-mour growth and metastasis. Communication between stromal and breast cancer cells consists of the secretion of factors that provoke a series of cell signalling that influence cell fate and tis-sue microenvironment, by favouring tumour cell survival and motility. Here, we present the c10orf118 protein expressed in high amounts by breast tumour cells as a new regulator in hya-luronan synthesis. This protein is found both in Golgi and secreted in the extracellular matrix, whereas its role is still unknown. The secreted c10orf118 is found to induce hyaluronan synthase 2 in normal fibroblasts. Importantly, high expression of c10orf118 is positively correlated to pa-tient’s survival and to a low metastasis. Abstract Interaction between cancer cells and their microenvironment is central in defining the fate of cancer development. Tumour cells secrete signals (cytokines, chemokines, growth factors) that modify the surrounding area, while the niche supplies structures and activities necessary for tumour maintenance and growth. Hyaluronan (HA) is a glycosaminoglycan that constitute cancer cell niche and is known to influence tumour functions such as proliferation, migration and neoangiogenesis. The knowledge of the factors regulating HA synthesis and size is crucial in understanding the mechanisms sustaining tumour development. Here we show that a yet uncharacterized protein secreted by breast tumour cell lines, named c10orf118 (accession number NM_018017 in NCBI/BLAST, and Q7z3E2 according to the Uniprot identifier), with a predicted length of 898 amino acids, can induce the secretion of HA by stromal fibroblasts through the up-regulation of the hyaluronan synthase 2 gene (HAS2). Intracellularly, this protein is localized in the Golgi apparatus with a possible role in vesicle maturation and transport. The expression of c10orf118 was verified in breast cancer patient specimens and was found to be associated with the presence of estrogen receptor that characterizes a good patient survival. We suggest c10orf118 as a new player that influences the HA amount in breast cancer microenvironment and is associated with low aggressiveness of cancer.
Collapse
|
11
|
Deng S, Liu J, Wu X, Lu W. Golgi Apparatus: A Potential Therapeutic Target for Autophagy-Associated Neurological Diseases. Front Cell Dev Biol 2020; 8:564975. [PMID: 33015059 PMCID: PMC7509445 DOI: 10.3389/fcell.2020.564975] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 08/17/2020] [Indexed: 12/13/2022] Open
Abstract
Autophagy has dual effects in human diseases: appropriate autophagy may protect cells from stress, while excessive autophagy may cause cell death. Additionally, close interactions exist between autophagy and the Golgi. This review outlines recent advances regarding the role of the Golgi apparatus in autophagy. The signaling processes of autophagy are dependent on the normal function of the Golgi. Specifically, (i) autophagy-related protein 9 is mainly located in the Golgi and forms new autophagosomes in response to stressors; (ii) Golgi fragmentation is induced by Golgi-related proteins and accompanied with autophagy induction; and (iii) the endoplasmic reticulum-Golgi intermediate compartment and the reticular trans-Golgi network play essential roles in autophagosome formation to provide a template for lipidation of microtubule-associated protein 1A/1B-light chain 3 and induce further ubiquitination. Golgi-related proteins regulate formation of autophagosomes, and disrupted formation of autophagy can influence Golgi function. Notably, aberrant autophagy has been demonstrated to be implicated in neurological diseases. Thus, targeted therapies aimed at protecting the Golgi or regulating Golgi proteins might prevent or ameliorate autophagy-related neurological diseases. Further studies are needed to investigate the potential application of Golgi therapy in autophagy-based neurological diseases.
Collapse
Affiliation(s)
- Shuwen Deng
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Jia Liu
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Xiaomei Wu
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Wei Lu
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| |
Collapse
|
12
|
Bajaj R, Kundu ST, Grzeskowiak CL, Fradette JJ, Scott KL, Creighton CJ, Gibbons DL. IMPAD1 and KDELR2 drive invasion and metastasis by enhancing Golgi-mediated secretion. Oncogene 2020; 39:5979-5994. [PMID: 32753652 PMCID: PMC7539228 DOI: 10.1038/s41388-020-01410-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 07/14/2020] [Accepted: 07/23/2020] [Indexed: 01/12/2023]
Abstract
Non-small cell lung cancer (NSCLC) is the deadliest form of cancer worldwide, due in part to its proclivity to metastasize. Identifying novel drivers of invasion and metastasis holds therapeutic potential for the disease. We conducted a gain-of-function invasion screen, which identified two separate hits, IMPAD1 and KDELR2, as robust, independent drivers of lung cancer invasion and metastasis. Given that IMPAD1 and KDELR2 are known to be localized to the ER-Golgi pathway, we studied their common mechanism of driving in vitro invasion and in vivo metastasis and demonstrated that they enhance Golgi-mediated function and secretion. Therapeutically inhibiting matrix metalloproteases (MMPs) suppressed both IMPAD1- and KDELR2-mediated invasion. The hits from this unbiased screen and the mechanistic validation highlight Golgi function as one of the key cellular features altered during invasion and metastasis.
Collapse
Affiliation(s)
- Rakhee Bajaj
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Samrat T Kundu
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.
| | - Caitlin L Grzeskowiak
- Department of Molecular and Human Genetics, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Medicine, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Jared J Fradette
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Kenneth L Scott
- Department of Medicine, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Chad J Creighton
- Department of Medicine, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Don L Gibbons
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.
| |
Collapse
|
13
|
Annaert W, Kaether C. Bring it back, bring it back, don't take it away from me - the sorting receptor RER1. J Cell Sci 2020; 133:133/17/jcs231423. [PMID: 32873699 DOI: 10.1242/jcs.231423] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The quote "bring it back, bring it back, don't take it away from me" from Queen's Love of my life describes the function of the sorting receptor RER1, a 23 kDa protein with four transmembrane domains (TMDs) that localizes to the intermediate compartment and the cis-Golgi. From there it returns escaped proteins that are not supposed to leave the endoplasmic reticulum (ER) back to it. Unique about RER1 is its ability to recognize its ligands through binding motifs in TMDs. Among its substrates are ER-resident proteins, as well as unassembled subunits of multimeric complexes that are retrieved back into the ER, this way guarding the full assembly of their respective complexes. The basic mechanisms for RER1-dependent retrieval have been already elucidated some years ago in yeast. More recently, several important cargoes of RER1 have been described in mammalian cells, and the in vivo role of RER1 is being unveiled by using mouse models. In this Review, we give an overview of the cell biology of RER1 in different models, discuss its controversial role in the brain and provide an outlook on future directions for RER1 research.
Collapse
Affiliation(s)
- Wim Annaert
- VIB Center for Brain and Disease Research & KU Leuven, Department of Neurosciences, Gasthuisberg, B-3000 Leuven, Belgium
| | - Christoph Kaether
- Leibniz Institut für Alternsforschung-Fritz Lipmann Institut, 07745 Jena, Germany
| |
Collapse
|
14
|
Medrano-Soto A, Ghazi F, Hendargo KJ, Moreno-Hagelsieb G, Myers S, Saier MH. Expansion of the Transporter-Opsin-G protein-coupled receptor superfamily with five new protein families. PLoS One 2020; 15:e0231085. [PMID: 32320418 PMCID: PMC7176098 DOI: 10.1371/journal.pone.0231085] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 03/17/2020] [Indexed: 02/06/2023] Open
Abstract
Here we provide bioinformatic evidence that the Organo-Arsenical Exporter (ArsP), Endoplasmic Reticulum Retention Receptor (KDELR), Mitochondrial Pyruvate Carrier (MPC), L-Alanine Exporter (AlaE), and the Lipid-linked Sugar Translocase (LST) protein families are members of the Transporter-Opsin-G Protein-coupled Receptor (TOG) Superfamily. These families share domains homologous to well-established TOG superfamily members, and their topologies of transmembranal segments (TMSs) are compatible with the basic 4-TMS repeat unit characteristic of this Superfamily. These repeat units tend to occur twice in proteins as a result of intragenic duplication events, often with subsequent gain/loss of TMSs in many superfamily members. Transporters within the ArsP family allow microbial pathogens to expel toxic arsenic compounds from the cell. Members of the KDELR family are involved in the selective retrieval of proteins that reside in the endoplasmic reticulum. Proteins of the MPC family are involved in the transport of pyruvate into mitochondria, providing the organelle with a major oxidative fuel. Members of family AlaE excrete L-alanine from the cell. Members of the LST family are involved in the translocation of lipid-linked glucose across the membrane. These five families substantially expand the range of substrates of transport carriers in the superfamily, although KDEL receptors have no known transport function. Clustering of protein sequences reveals the relationships among families, and the resulting tree correlates well with the degrees of sequence similarity documented between families. The analyses and programs developed to detect distant relatedness, provide insights into the structural, functional, and evolutionary relationships that exist between families of the TOG superfamily, and should be of value to many other investigators.
Collapse
Affiliation(s)
- Arturo Medrano-Soto
- Department of Molecular Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - Faezeh Ghazi
- Department of Molecular Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - Kevin J. Hendargo
- Department of Molecular Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | | | - Scott Myers
- Department of Molecular Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - Milton H. Saier
- Department of Molecular Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
- * E-mail:
| |
Collapse
|
15
|
Mironov AA, Beznoussenko GV. Models of Intracellular Transport: Pros and Cons. Front Cell Dev Biol 2019; 7:146. [PMID: 31440506 PMCID: PMC6693330 DOI: 10.3389/fcell.2019.00146] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/16/2019] [Indexed: 12/22/2022] Open
Abstract
Intracellular transport is one of the most confusing issues in the field of cell biology. Many different models and their combinations have been proposed to explain the experimental data on intracellular transport. Here, we analyse the data related to the mechanisms of endoplasmic reticulum-to-Golgi and intra-Golgi transport from the point of view of the main models of intracellular transport; namely: the vesicular model, the diffusion model, the compartment maturation–progression model, and the kiss-and-run model. This review initially describes our current understanding of Golgi function, while highlighting the recent progress that has been made. It then continues to discuss the outstanding questions and potential avenues for future research with regard to the models of these transport steps. To compare the power of these models, we have applied the method proposed by K. Popper; namely, the formulation of prohibitive observations according to, and the consecutive evaluation of, previous data, on the basis on the new models. The levels to which the different models can explain the experimental observations are different, and to date, the most powerful has been the kiss-and-run model, whereas the least powerful has been the diffusion model.
Collapse
Affiliation(s)
- Alexander A Mironov
- Department of Cell Biology, The FIRC Institute of Molecular Oncology, Milan, Italy
| | | |
Collapse
|
16
|
Chen L, Liu YC, Tan H, Zhang Y, Xu J, Liu WL, Li ZY, Li WP. Santacruzamate A Ameliorates AD-Like Pathology by Enhancing ER Stress Tolerance Through Regulating the Functions of KDELR and Mia40-ALR in vivo and in vitro. Front Cell Neurosci 2019; 13:61. [PMID: 30886573 PMCID: PMC6409322 DOI: 10.3389/fncel.2019.00061] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 02/06/2019] [Indexed: 11/13/2022] Open
Abstract
Aggregated amyloid-β protein (Aβ) and Aβ-induced neuronal apoptosis have been implicated as critical factors in the pathophysiology of Alzheimer’s disease (AD). Certain preclinical results have indicated that the increased accumulation of protein aggregates in AD-affected neurons activates the unfolded protein response (UPR), a pathological phenomenon, which predominantly mediates the aberrant endoplasmic reticulum (ER) stress and apoptotic cascades in neuronal cells. In the present study, we confirmed that Santacruzamate A (STA, a natural product isolated from a Panamanian marine cyanobacterium) attenuates Aβ protein fragment 25–35 (Aβ25–35)-induced toxicity in PC12 cells and rescues cognitive deficits in APPswe/PS1dE9 mice by enhancing ER stress tolerance. We first demonstrated the anti-apoptotic effects of STA by evaluating caspase-3 activity, annexin V/propidium iodide (PI) staining, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Behavioral testing of STA-treated APPswe/PS1dE9 mice showed that the pronounced memory impairments were ameliorated and that the consolidated memories were stably maintained over a 2-week period. The mechanistic studies provided evidence that STA inhibited Aβ25–35-induced UPR and ER stress by regulating the ER retention signal (KDEL) receptor, which reinforced the retention of resident chaperones in the ER lumen. Furthermore, STA regulated the expression of the mitochondrial intermembrane space assembly protein 40 (Mia40) and augmenter of liver regeneration (ALR), which ultimately attenuated the mitochondrial fission and apoptosis pathways. Together, our present findings suggest that the KDEL receptor and Mia40-ALR play a role in mitigating Aβ25–35-induced neurotoxicity, which might in turn positively regulate learning and memory. These observations support that STA may be a promising agent for reversing the progression of AD.
Collapse
Affiliation(s)
- Lei Chen
- Shenzhen Key Laboratory of Neurosurgery, Brain Center, Shenzhen Second People's Hospital, Shenzhen University 1st Affiliated Hospital, Shenzhen, China
| | | | - Hui Tan
- Shenzhen Key Laboratory of Neurosurgery, Brain Center, Shenzhen Second People's Hospital, Shenzhen University 1st Affiliated Hospital, Shenzhen, China
| | - Yuan Zhang
- Shenzhen Key Laboratory of Neurosurgery, Brain Center, Shenzhen Second People's Hospital, Shenzhen University 1st Affiliated Hospital, Shenzhen, China
| | - Ji Xu
- Shenzhen Key Laboratory of Neurosurgery, Brain Center, Shenzhen Second People's Hospital, Shenzhen University 1st Affiliated Hospital, Shenzhen, China
| | - Wen-Lan Liu
- Shenzhen Key Laboratory of Neurosurgery, Brain Center, Shenzhen Second People's Hospital, Shenzhen University 1st Affiliated Hospital, Shenzhen, China
| | - Zong-Yang Li
- Shenzhen Key Laboratory of Neurosurgery, Brain Center, Shenzhen Second People's Hospital, Shenzhen University 1st Affiliated Hospital, Shenzhen, China
| | - Wei-Ping Li
- Shenzhen Key Laboratory of Neurosurgery, Brain Center, Shenzhen Second People's Hospital, Shenzhen University 1st Affiliated Hospital, Shenzhen, China
| |
Collapse
|
17
|
Singh M, Beri D, Nageshan RK, Chavaan L, Gadara D, Poojary M, Subramaniam S, Tatu U. A secreted Heat shock protein 90 of Trichomonas vaginalis. PLoS Negl Trop Dis 2018; 12:e0006493. [PMID: 29768419 PMCID: PMC5973626 DOI: 10.1371/journal.pntd.0006493] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 05/29/2018] [Accepted: 05/03/2018] [Indexed: 11/18/2022] Open
Abstract
Trichomonas vaginalis is a causative agent of Trichomoniasis, a leading non-viral sexually transmitted disease worldwide. In the current study, we show Heat shock protein 90 is essential for its growth. Upon genomic analysis of the parasite, it was found to possess seven ORFs which could potentially encode Hsp90 isoforms. We identified a cytosolic Hsp90 homolog, four homologs which can align to truncated cytosolic Hsp90 gene products along with two Grp94 homologs (ER isoform of Hsp90). However, both Grp94 orthologs lacked an ER retention motif. In cancer cells, it is very well established that Hsp90 is secreted and regulates key clients involved in metastases, migration, and invasion. Since Trichomonas Grp94 lacks ER retention motif, we examined the possibility of its secretion. By using cell biology and biochemical approaches we show that the Grp94 isoform of Hsp90 is secreted by the parasite by the classical ER-Golgi pathway. This is the first report of a genome encoded secreted Hsp90 in a clinically important parasitic protozoan. Hsp90 is an essential chaperone in eukaryotes and it is often described as a master regulator of cellular homeostasis. In addition to its well-known functions inside the cell, extracellular Hsp90 has also been implicated in migration and invasion of tumor cells. We have, for the first time, identified the presence of an extracellular Hsp90 in a parasitic protozoan, Trichomonas vaginalis. The extracellular Hsp90 is a Grp94 homolog that lacks a canonical ER retention signal. Our analysis of Grp94 sequences from protozoa shows that it is uncommon for a Grp94 to lack ER retention signal. In the current study, we characterized the biochemical parameters and established the extracellular localization of this Hsp90 paralog. This secreted Hsp90 in Trichomonas can potentially modulate host-pathogen interaction.
Collapse
Affiliation(s)
- Meetali Singh
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Divya Beri
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | | | - Leena Chavaan
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Darshak Gadara
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Mukta Poojary
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Suraj Subramaniam
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Utpal Tatu
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
- * E-mail:
| |
Collapse
|
18
|
Gosavi P, Houghton FJ, McMillan PJ, Hanssen E, Gleeson PA. The Golgi ribbon in mammalian cells negatively regulates autophagy by modulating mTOR activity. J Cell Sci 2018; 131:jcs.211987. [PMID: 29361552 DOI: 10.1242/jcs.211987] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/20/2017] [Indexed: 12/25/2022] Open
Abstract
In vertebrates, individual Golgi stacks are joined into a compact ribbon structure; however, the relevance of a ribbon structure has been elusive. Here, we exploit the finding that the membrane tether of the trans-Golgi network, GCC88 (encoded by GCC1), regulates the balance between Golgi mini-stacks and the Golgi ribbon. Loss of Golgi ribbons in stable cells overexpressing GCC88 resulted in compromised mechanistic target of rapamycin (mTOR) signaling and a dramatic increase in LC3-II-positive autophagosomes, whereas RNAi-mediated depletion of GCC88 restored the Golgi ribbon and reduced autophagy. mTOR was absent from dispersed Golgi mini-stacks whereas recruitment of mTOR to lysosomes was unaffected. We show that the Golgi ribbon is a site for localization and activation of mTOR, a process dependent on the ribbon structure. We demonstrate a strict temporal sequence of fragmentation of Golgi ribbon, loss of Golgi mTOR and subsequent increased autophagy. Golgi ribbon fragmentation has been reported in various neurodegenerative diseases and we demonstrate the potential relevance of our findings in neuronal cells using a model of neurodegeneration. Overall, this study highlights a role for the Golgi ribbon in pathways central to cellular homeostasis.This article has an associated First Person interview with the first author of the paper.
Collapse
Affiliation(s)
- Prajakta Gosavi
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Fiona J Houghton
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Paul J McMillan
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia.,Biological Optical Microscopy Platform, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Eric Hanssen
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia.,Advanced Microscopy Facility, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Paul A Gleeson
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| |
Collapse
|
19
|
Gosavi P, Gleeson PA. The Function of the Golgi Ribbon Structure - An Enduring Mystery Unfolds! Bioessays 2017; 39. [PMID: 28984991 DOI: 10.1002/bies.201700063] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 08/31/2017] [Indexed: 12/13/2022]
Abstract
The Golgi apparatus in vertebrate cells consists of individual Golgi stacks fused together in a continuous ribbon structure. The ribbon structure per se is not required to mediate the classical functions of this organelle and the relevance of the "ribbon" structure has been a mystery since first identified ultrastructurally in the 1950s. Recent advances recognize a role for the Golgi apparatus in a range of cellular processes, some mediated by signaling networks which are regulated at the Golgi. Here we review the cellular processes and signaling events regulated by the Golgi apparatus and, in particular, explore an emerging theme that the ribbon structure of the Golgi contributes directly to the regulation of these higher order functions.
Collapse
Affiliation(s)
- Prajakta Gosavi
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria, 3010, Australia
| | - Paul A Gleeson
- The Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria, 3010, Australia
| |
Collapse
|
20
|
Ayala I, Colanzi A. Mitotic inheritance of the Golgi complex and its role in cell division. Biol Cell 2017; 109:364-374. [PMID: 28799169 DOI: 10.1111/boc.201700032] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/04/2017] [Accepted: 08/04/2017] [Indexed: 12/30/2022]
Abstract
The Golgi apparatus plays essential roles in the processing and sorting of proteins and lipids, but it can also act as a signalling hub and a microtubule-nucleation centre. The Golgi complex (GC) of mammalian cells is composed of stacks connected by tubular bridges to form a continuous membranous system. In spite of this structural complexity, the GC is highly dynamic, and this feature becomes particularly evident during mitosis, when the GC undergoes a multi-step disassembly process that allows its correct partitioning and inheritance by daughter cells. Strikingly, different steps of Golgi disassembly control mitotic entry and progression, indicating that cells actively monitor Golgi integrity during cell division. Here, we summarise the basic mechanisms and the molecular players that are involved in Golgi disassembly, focussing in particular on recent studies that have revealed the fundamental signalling pathways that connect Golgi inheritance to mitotic entry and progression.
Collapse
Affiliation(s)
- Inmaculada Ayala
- Institute of Protein Biochemistry, National Research Council, Naples, 80131, Italy
| | - Antonino Colanzi
- Institute of Protein Biochemistry, National Research Council, Naples, 80131, Italy
| |
Collapse
|
21
|
Michalska M, Wolf P. Pseudomonas Exotoxin A: optimized by evolution for effective killing. Front Microbiol 2015; 6:963. [PMID: 26441897 PMCID: PMC4584936 DOI: 10.3389/fmicb.2015.00963] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 08/31/2015] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas Exotoxin A (PE) is the most toxic virulence factor of the pathogenic bacterium Pseudomonas aeruginosa. This review describes current knowledge about the intoxication pathways of PE. Moreover, PE represents a remarkable example for pathoadaptive evolution, how bacterial molecules have been structurally and functionally optimized under evolutionary pressure to effectively impair and kill their host cells.
Collapse
Affiliation(s)
- Marta Michalska
- Department of Urology, Medical Center, University of Freiburg Freiburg, Germany
| | - Philipp Wolf
- Department of Urology, Medical Center, University of Freiburg Freiburg, Germany
| |
Collapse
|
22
|
Huang HH, Hassinen A, Sundaram S, Spiess AN, Kellokumpu S, Stanley P. GnT1IP-L specifically inhibits MGAT1 in the Golgi via its luminal domain. eLife 2015; 4. [PMID: 26371870 PMCID: PMC4572887 DOI: 10.7554/elife.08916] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 08/12/2015] [Indexed: 12/15/2022] Open
Abstract
Mouse GnT1IP-L, and membrane-bound GnT1IP-S (MGAT4D) expressed in cultured cells
inhibit MGAT1, the N-acetylglucosaminyltransferase that initiates the synthesis of
hybrid and complex N-glycans. However, it is not known where in the secretory pathway
GnT1IP-L inhibits MGAT1, nor whether GnT1IP-L inhibits other N-glycan branching
N-acetylglucosaminyltransferases of the medial Golgi. We show here that the luminal
domain of GnT1IP-L contains its inhibitory activity. Retention of GnT1IP-L in the
endoplasmic reticulum (ER) via the N-terminal region of human invariant chain p33,
with or without C-terminal KDEL, markedly reduced inhibitory activity. Dynamic
fluorescent resonance energy transfer (FRET) and bimolecular fluorescence
complementation (BiFC) assays revealed homomeric interactions for GnT1IP-L in the ER,
and heteromeric interactions with MGAT1 in the Golgi. GnT1IP-L did not generate a
FRET signal with MGAT2, MGAT3, MGAT4B or MGAT5 medial Golgi GlcNAc-tranferases.
GnT1IP/Mgat4d transcripts are expressed predominantly in
spermatocytes and spermatids in mouse, and are reduced in men with impaired
spermatogenesis. DOI:http://dx.doi.org/10.7554/eLife.08916.001 Proteins are made up of chains of amino acids that fold into three-dimensional shapes
and many are assembled in a cell compartment known as the endoplasmic reticulum. From
here, these new proteins move to another compartment called the Golgi, where they may
be further modified before they are transported to their final destination in the
cell. One way that proteins may be modified is known as glycosylation, in which sugar
molecules are attached to specific amino acids. Some sugar molecules can act as
labels that ensure the new proteins are transported to the correct destination in the
cell. For proteins that are delivered to the surface of the cell, the sugar molecules
can also play important roles in communication with other cells. A simple sugar molecule, or a complex arrangement of many sugar molecules, may be
attached to an amino acid by glycosylation. An enzyme called MGAT1 controls the
synthesis of sugars called complex N-glycans in the Golgi. In 2010, researchers
reported that a glycoprotein called GnT1IP-L binds to MGAT1 and inhibits its
activity, thereby blocking the production of complex N-glycans. GnT1IP-L was found in
the endoplasmic reticulum and Golgi, but it was not clear how it inhibits MGAT1. Huang et al.—including some of the researchers from the 2010 study—have
now investigated the activity of GnT1IP-L in cells grown in the laboratory using
several biochemical techniques. The experiments show that GnT1IP-L only binds to
MGAT1 when both proteins are in the Golgi. There are three sections (or
‘domains’) in GnT1IP-L, but Huang et al. found that only the domain
that is on the inside of the Golgi is involved in this interaction. Previous work indicated that GnT1IP-L may be involved in the formation of sperm in
mice. Huang et al. have now analyzed previously published data on samples of testis
tissue from human patients and found that the gene that encodes GnT1IP-L is present
in very low amounts in patients whose sperm do not develop properly. Huang et al.'s findings suggest that GnT1IP-L may inhibit MGAT1 to control the
glycosylation of proteins in the Golgi of developing sperm. The next step is to test
this hypothesis by generating mutant mice that lack GnT1IP-L, or to make GnT1P-L in
other cells in which it is not normally made, to find out if this affects the
production of sperm. DOI:http://dx.doi.org/10.7554/eLife.08916.002
Collapse
Affiliation(s)
- Hung-Hsiang Huang
- Department of Cell Biology, Albert Einstein College of Medicine, New York, United States
| | - Antti Hassinen
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Subha Sundaram
- Department of Cell Biology, Albert Einstein College of Medicine, New York, United States
| | | | - Sakari Kellokumpu
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Pamela Stanley
- Department of Cell Biology, Albert Einstein College of Medicine, New York, United States
| |
Collapse
|
23
|
Lugo MR, Merrill AR. The Father, Son and Cholix Toxin: The Third Member of the DT Group Mono-ADP-Ribosyltransferase Toxin Family. Toxins (Basel) 2015. [PMID: 26213968 PMCID: PMC4549722 DOI: 10.3390/toxins7082757] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The cholix toxin gene (chxA) was first identified in V. cholerae strains in 2007, and the protein was identified by bioinformatics analysis in 2008. It was identified as the third member of the diphtheria toxin group of mono-ADP-ribosyltransferase toxins along with P. aeruginosa exotoxin A and C. diphtheriae diphtheria toxin. Our group determined the structure of the full-length, three-domain cholix toxin at 2.1 Å and its C-terminal catalytic domain (cholixc) at 1.25 Å resolution. We showed that cholix toxin is specific for elongation factor 2 (diphthamide residue), similar to exotoxin A and diphtheria toxin. Cholix toxin possesses molecular features required for infection of eukaryotes by receptor-mediated endocytosis, translocation to the host cytoplasm and inhibition of protein synthesis. More recently, we also solved the structure of full-length cholix toxin in complex with NAD+ and proposed a new kinetic model for cholix enzyme activity. In addition, we have taken a computational approach that revealed some important properties of the NAD+-binding pocket at the residue level, including the role of crystallographic water molecules in the NAD+ substrate interaction. We developed a pharmacophore model of cholix toxin, which revealed a cationic feature in the side chain of cholix toxin active-site inhibitors that may determine the active pose. Notably, several recent reports have been published on the role of cholix toxin as a major virulence factor in V. cholerae (non-O1/O139 strains). Additionally, FitzGerald and coworkers prepared an immunotoxin constructed from domains II and III as a cancer treatment strategy to complement successful immunotoxins derived from P. aeruginosa exotoxin A.
Collapse
Affiliation(s)
- Miguel R Lugo
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
| | - A Rod Merrill
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
| |
Collapse
|
24
|
KDEL Receptors Assist Dengue Virus Exit from the Endoplasmic Reticulum. Cell Rep 2015; 10:1496-1507. [PMID: 25753416 DOI: 10.1016/j.celrep.2015.02.021] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 10/16/2014] [Accepted: 02/04/2015] [Indexed: 11/23/2022] Open
Abstract
Membrane receptors at the surface of target cells are key host factors for virion entry; however, it is unknown whether trafficking and secretion of progeny virus requires host intracellular receptors. In this study, we demonstrate that dengue virus (DENV) interacts with KDEL receptors (KDELR), which cycle between the ER and Golgi apparatus, for vesicular transport from ER to Golgi. Depletion of KDELR by siRNA reduced egress of both DENV progeny and recombinant subviral particles (RSPs). Coimmunoprecipitation of KDELR with dengue structural protein prM required three positively charged residues at the N terminus, whose mutation disrupted protein interaction and inhibited RSP transport from the ER to the Golgi. Finally, siRNA depletion of class II Arfs, which results in KDELR accumulation in the Golgi, phenocopied results obtained with mutagenized prME and KDELR knockdown. Our results have uncovered a function for KDELR as an internal receptor involved in DENV trafficking.
Collapse
|
25
|
Wiersma VR, Michalak M, Abdullah TM, Bremer E, Eggleton P. Mechanisms of Translocation of ER Chaperones to the Cell Surface and Immunomodulatory Roles in Cancer and Autoimmunity. Front Oncol 2015; 5:7. [PMID: 25688334 PMCID: PMC4310273 DOI: 10.3389/fonc.2015.00007] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 01/10/2015] [Indexed: 01/12/2023] Open
Abstract
Endoplasmic reticulum (ER) chaperones (e.g., calreticulin, heat shock proteins, and isomerases) perform a multitude of functions within the ER. However, many of these chaperones can translocate to the cytosol and eventually the surface of cells, particularly during ER stress induced by e.g., drugs, UV irradiation, and microbial stimuli. Once on the cell surface or in the extracellular space, the ER chaperones can take on immunogenic characteristics, as mostly described in the context of cancer, appearing as damage-associated molecular patterns recognized by the immune system. How ER chaperones relocate to the cell surface and interact with other intracellular proteins appears to influence whether a tumor cell is targeted for cell death. The relocation of ER proteins to the cell surface can be exploited to target cancer cells for elimination by immune mechanism. Here we evaluate the evidence for the different mechanisms of ER protein translocation and binding to the cell surface and how ER protein translocation can act as a signal for cancer cells to undergo killing by immunogenic cell death and other cell death pathways. The release of chaperones can also exacerbate underlying autoimmune conditions, such as rheumatoid arthritis and multiple sclerosis, and the immunomodulatory role of extracellular chaperones as potential cancer immunotherapies requires cautious monitoring, particularly in cancer patients with underlying autoimmune disease.
Collapse
Affiliation(s)
- Valerie R. Wiersma
- Department of Surgery, Translational Surgical Oncology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Marek Michalak
- University of Exeter Medical School, Exeter Devon, UK
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | | | - Edwin Bremer
- Department of Surgery, Translational Surgical Oncology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- University of Exeter Medical School, Exeter Devon, UK
| | - Paul Eggleton
- University of Exeter Medical School, Exeter Devon, UK
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
26
|
Luini A, Mavelli G, Jung J, Cancino J. Control systems and coordination protocols of the secretory pathway. F1000PRIME REPORTS 2014; 6:88. [PMID: 25374666 PMCID: PMC4191269 DOI: 10.12703/p6-88] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Like other cellular modules, the secretory pathway and the Golgi complex are likely to be supervised by control systems that support homeostasis and optimal functionality under all conditions, including external and internal perturbations. Moreover, the secretory apparatus must be functionally connected with other cellular modules, such as energy metabolism and protein degradation, via specific rules of interaction, or “coordination protocols”. These regulatory devices are of fundamental importance for optimal function; however, they are generally “hidden” at steady state. The molecular components and the architecture of the control systems and coordination protocols of the secretory pathway are beginning to emerge through studies based on the use of controlled transport-specific perturbations aimed specifically at the detection and analysis of these internal regulatory devices.
Collapse
Affiliation(s)
- Alberto Luini
- Consiglio Nazionale delle Ricerche (CNR), Istituto di Biochimica delle Proteine (IBP)Via Pietro Castellino 111, 80131 NapoliItaly
- Telethon Institute of Genetics and Medicine (TIGEM)Via Pietro Castellino 111, 80131 NapoliItaly
| | - Gabriella Mavelli
- Istituto di Analisi dei Sistemi ed Informatica Antonio Ruberti, Consiglio Nazionale delle RicercheViale Manzoni 30, 00185 RomaItaly
| | - Juan Jung
- Istituto di Ricovero e Cura a Carattere Scientifico-SDN80143 NapoliItaly
| | - Jorge Cancino
- Consiglio Nazionale delle Ricerche (CNR), Istituto di Biochimica delle Proteine (IBP)Via Pietro Castellino 111, 80131 NapoliItaly
- Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andrés BelloQuillota 980, 2520000 Viña del MarChile
| |
Collapse
|
27
|
The Histochem Cell Biol conspectus: the year 2013 in review. Histochem Cell Biol 2014; 141:337-63. [PMID: 24610091 PMCID: PMC7087837 DOI: 10.1007/s00418-014-1207-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2014] [Indexed: 11/29/2022]
Abstract
Herein, we provide a brief synopsis of all manuscripts published in Histochem Cell Biol in the year 2013. For ease of reference, we have divided the manuscripts into the following categories: Advances in Methodologies; Molecules in Health and Disease; Organelles, Subcellular Structures and Compartments; Golgi Apparatus; Intermediate Filaments and Cytoskeleton; Connective Tissue and Extracellular Matrix; Autophagy; Stem Cells; Musculoskeletal System; Respiratory and Cardiovascular Systems; Gastrointestinal Tract; Central Nervous System; Peripheral Nervous System; Excretory Glands; Kidney and Urinary Bladder; and Male and Female Reproductive Systems. We hope that the readership will find this annual journal synopsis of value and serve as a quick, categorized reference guide for “state-of-the-art” manuscripts in the areas of histochemistry, immunohistochemistry, and cell biology.
Collapse
|
28
|
Tröße C, Nilsen F, Dalvin S. RNA interference mediated knockdown of the KDEL receptor and COPB2 inhibits digestion and reproduction in the parasitic copepod Lepeophtheirus salmonis. Comp Biochem Physiol B Biochem Mol Biol 2013; 170:1-9. [PMID: 24382395 DOI: 10.1016/j.cbpb.2013.12.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 12/18/2013] [Accepted: 12/19/2013] [Indexed: 11/29/2022]
Abstract
Retrograde transport of proteins from the endoplasmic reticulum to the Golgi is an essential part of the secretory pathway that all newly synthesised secreted and membrane proteins in eukaryotic cells undergo. The aim of this study was to characterise two components of the retrograde transport pathway in the parasitic copepod Lepeophtheirus salmonis (salmon louse) on a molecular and functional level. LsKDELR and LsCOPB2 were confirmed to be the salmon louse homologues of the chosen target proteins by sequence similarity. Ontogenetic analysis by qRT-PCR revealed the highest expression levels of both genes in adult females and the earliest larval stage. LsKDELR and LsCOPB2 localisation in adult females was detected by immunofluorescence and in situ hybridisation, respectively. Both LsKDELR and LsCOPB2 were found in the ovaries, the oocytes and the gut. LsKDELR and LsCOPB2 were knocked down by RNA interference in preadult females, which was confirmed by qRT-PCR. LsCOPB2 knockdown lice had a significantly higher mortality and failed to develop normally, while both LsCOPB2 and LsKDELR knockdown caused disturbed digestion and the absence of egg strings. This shows the potential of LsKDELR and LsCOPB2 as suitable target candidates for new pest control methods.
Collapse
Affiliation(s)
- Christiane Tröße
- Department of Biology, University of Bergen, P.O. Box 7803, 5020 Bergen, Norway.
| | - Frank Nilsen
- SLRC-Sea Lice Research Centre, Department of Biology, University of Bergen, P.O. Box 7803, 5020 Bergen, Norway
| | - Sussie Dalvin
- SLRC-Sea Lice Research Centre, Institute of Marine Research, P.O. Box 1870, 5817 Bergen, Norway
| |
Collapse
|
29
|
Coria AS, Masseroni ML, Díaz Añel AM. Regulation of PKD1-mediated Golgi to cell surface trafficking by Gαq subunits. Biol Cell 2013; 106:30-43. [PMID: 24175919 DOI: 10.1111/boc.201300052] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 10/28/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND INFORMATION Heterotrimeric GTP-binding proteins play a key role in cell trafficking regulation. Above all, specific Gβγ subunits have been shown to be a major component of a signal transduction pathway, which also involves phospholipases C (PLC), protein kinases C (PKC) and D (PKD), whose main function is to regulate transport between Golgi and plasma membrane. It was the involvement of PLC which led us to study the role of the other member of this G protein family, the α subunits, in the regulation of membrane fission at the Golgi apparatus. RESULTS Among constitutive active (QL) variants of different G protein α subunit sub-families, only GαqQL subunits were able to induce Golgi fragmentation, a phenotype that mainly reflects a membrane fission increase at this organelle. This phenotype was not observed with a GαqQL palmitoylation mutant, showing the need for a membrane-bounded subunit. Besides, GαqQL-dependent Golgi fission was blocked by specific PLC and PKC inhibitors, and in the presence of a PKD1-kinase dead variant. In addition, GαqQL was the only α subunit capable of inducing PKD1 phosphorylation. Finally, Vesicular Stomatitis Virus thermosensitive mutant glycoprotein (VSVG tsO45) transport assays have demonstrated that GαqQL acts directly on Golgi membranes to regulate trafficking between this organelle and plasma membrane. CONCLUSIONS All these results indicate Gαq subunits for the first time as a regulator of PKD-mediated intracellular trafficking between Golgi apparatus and plasma membrane, opening new perspectives in the understanding of internal trafficking regulation by external signals through G protein-coupled receptors.
Collapse
Affiliation(s)
- A Soledad Coria
- Laboratory of Neurobiology and Cell Biology, Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC), CONICET and Universidad Nacional de Córdoba. Friuli 2434, Barrio Parque Vélez Sarsfield, Córdoba 5016, Provincia de Córdoba, Argentina
| | | | | |
Collapse
|