1
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Niu H, Bi F, Zhao W, Xu Y, Han Q, Guo W, Chen Y. Smurf1 regulates ameloblast polarization by ubiquitination-mediated degradation of RhoA. Cell Prolif 2022; 56:e13387. [PMID: 36579844 PMCID: PMC10068949 DOI: 10.1111/cpr.13387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/06/2022] [Accepted: 12/12/2022] [Indexed: 12/30/2022] Open
Abstract
Cell polarity is essential for ameloblast differentiation and enamel formation. Smurf1 can mediate cell polarization through ubiquitination degradation of specific substrates. But it remains unclear whether Smurf1 could regulate ameloblast polarity and the underlying mechanism. Here, immuno-fluorescence staining and RT-qPCR were applied to detect the expression of Smurf1 and F-actin. A mouse lower incisor defect model was constructed. Scanning electron microscope, rat lower incisor culture, western blot, wound healing assay and trans-well migration assay were performed to detect the influence of Smurf1 knockdown on ameloblast. IF double staining, western blot and co-immunoprecipitation were conducted to detect the interaction between Smurf1 and RhoA. The in vivo experiment was also performed. We found that Smurf1 was mainly expressed in the membrane and cell cortex of ameloblast, similar to F-actin. Smurf1 expression increased along ameloblast polarization and differentiation. After knocking down Smurf1, the cytoskeleton and cell morphology changed and the cell polarity was damaged. Smurf1 regulated ameloblast polarity through ubiquitination degradation of activated RhoA in vitro. Local knockdown of Smurf1 in rat lower incisor ameloblast resulted in ameloblast polarity loss, enamel matrix secretion disorder and chalky enamel, but RhoA inhibitor Y-27632 could reverse this effect. Collectively, Smurf1 could regulate the polarization of ameloblast through ubiquitination degradation of activated RhoA, which contributed to the knowledge of tooth development and provided new research ideas for cell polarity.
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Affiliation(s)
- Haoman Niu
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Oral Pathology, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Fei Bi
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Pediatric Dentistry, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Wenjun Zhao
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Oral Pathology, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Yuchan Xu
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Pediatric Dentistry, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Qi Han
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Oral Pathology, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Weihua Guo
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Pediatric Dentistry, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Yu Chen
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.,Department of Oral Pathology, West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
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2
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Jamil F, Aslam L, Ali H, Shoukat K, Rasheed MA, Raza S, Ibrahim M. An In silico study of derivative of Newcastle disease virus epitopes based vaccine against Hemagglutunin neuraminidase protein. J Anim Sci 2022; 101:skac375. [PMID: 36371806 PMCID: PMC9883717 DOI: 10.1093/jas/skac375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 11/11/2022] [Indexed: 11/14/2022] Open
Abstract
The causative agent of Newcastle disease (ND) is Newcastle disease virus. It belongs to avian species of Orthoavulavirus, Avulavirinae subfamily and if left untreated it may cause epidemic in poultry. Many vaccines have been made against Newcastle disease based on inactivated and attenuated viruses but become useless due to the genetic changes in the virus. We have recently reported epitope based vaccine by using immunoinformatics approaches. The vaccine was previously constructed against Hemagglutunin neuraminidase protein of Newcastle disease virus. Here we extended our work to develop several chimera of the proposed vaccine to design a new multi-epitope vaccine by shuffling the cytotoxic T lymphocytes (CTL) segments of the vaccine. Total 5040 constructs have been analyzed by shuffling 7 CTL epitopes. Highest antigenic multi-epitope construct was selected for the further study. Our new multi-epitope vaccine (MEV) construct contains 259 amino acids and is immunogenic, more antigenic and non-allergen. The refinement of the structure of MEV construct was performed. Molecular docking analyses showed its maximum binding with avian Toll-like 4 receptor. Subsequently, immune simulations showed its predicted ability to induce the host primary and secondary responses. Study suggests that our new multi-epitope vaccine chimera is more effective and stable protein against Newcastle disease virus strains in Pakistan. However, further studies are required to validate the vaccine through In vitro and In vivo studies.
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Affiliation(s)
- Farrukh Jamil
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Sahiwal, Pakistan
| | - Laiba Aslam
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Sahiwal, Pakistan
| | - Hira Ali
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Sahiwal, Pakistan
| | - Kainaat Shoukat
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Sahiwal, Pakistan
| | - Muhammad Asif Rasheed
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Sahiwal, Pakistan
| | - Sohail Raza
- Institute of Microbiology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Ibrahim
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Sahiwal, Pakistan
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3
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Li X, Li L, Si X, Zhang Z, Ni Z, Zhou Y, Liu K, Xia W, Zhang Y, Gu X, Huang J, Yin C, Shao A, Jiang L. The regulatory roles of circular RNAs via autophagy in ischemic stroke. Front Neurol 2022; 13:963508. [PMID: 36330428 PMCID: PMC9623297 DOI: 10.3389/fneur.2022.963508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 09/07/2022] [Indexed: 11/24/2022] Open
Abstract
Ischemic stroke (IS) is a severe disease with a high disability, recurrence, and mortality rates. Autophagy, a highly conserved process that degrades damaged or aging organelles and excess cellular components to maintain homeostasis, is activated during IS. It influences the blood–brain barrier integrity and regulates apoptosis. Circular RNAs (circRNAs) are novel non-coding RNAs involved in IS-induced autophagy and participate in various pathological processes following IS. In addition, they play a role in autophagy regulation. This review summarizes current evidence on the roles of autophagy and circRNA in IS and the potential mechanisms by which circRNAs regulate autophagy to influence IS injury. This review serves as a basis for the clinical application of circRNAs as novel biomarkers and therapeutic targets in the future.
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Affiliation(s)
- Xiaoqin Li
- The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Lingfei Li
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaoli Si
- Department of Neurology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Zheng Zhang
- The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Zhumei Ni
- Department of Emergency, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yongji Zhou
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Keqin Liu
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Wenqing Xia
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yuyao Zhang
- The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Xin Gu
- The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Jinyu Huang
- Department of Cardiology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Congguo Yin
- The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- *Correspondence: Congguo Yin
| | - Anwen Shao
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Key Laboratory of Precise Treatment and Clinical Translational Research of Neurological Disease, Hangzhou, China
- Anwen Shao
| | - Lin Jiang
- The Fourth School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Lin Jiang
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4
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Omelchenko T. Cellular protrusions in 3D: Orchestrating early mouse embryogenesis. Semin Cell Dev Biol 2022; 129:63-74. [PMID: 35577698 DOI: 10.1016/j.semcdb.2022.05.005] [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: 02/23/2022] [Revised: 05/04/2022] [Accepted: 05/04/2022] [Indexed: 12/26/2022]
Abstract
Cellular protrusions generated by the actin cytoskeleton are central to the process of building the body of the embryo. Problems with cellular protrusions underlie human diseases and syndromes, including implantation defects and pregnancy loss, congenital birth defects, and cancer. Cells use protrusive activity together with actin-myosin contractility to create an ordered body shape of the embryo. Here, I review how actin-rich protrusions are used by two major morphological cell types, epithelial and mesenchymal cells, during collective cell migration to sculpt the mouse embryo body. Pre-gastrulation epithelial collective migration of the anterior visceral endoderm is essential for establishing the anterior-posterior body axis. Gastrulation mesenchymal collective migration of the mesoderm wings is crucial for body elongation, and somite and heart formation. Analysis of mouse mutants with disrupted cellular protrusions revealed the key role of protrusions in embryonic morphogenesis and embryo survival. Recent technical approaches have allowed examination of the mechanisms that control cell and tissue movements in vivo in the complex 3D microenvironment of living mouse embryos. Advancing our understanding of protrusion-driven morphogenesis should provide novel insights into human developmental disorders and cancer metastasis.
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Affiliation(s)
- Tatiana Omelchenko
- Laboratory of Mammalian Cell Biology and Development, The Rockefeller University, 1230 York Avenue, New York 10065, USA.
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5
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Machin PA, Tsonou E, Hornigold DC, Welch HCE. Rho Family GTPases and Rho GEFs in Glucose Homeostasis. Cells 2021; 10:cells10040915. [PMID: 33923452 PMCID: PMC8074089 DOI: 10.3390/cells10040915] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/11/2021] [Accepted: 04/13/2021] [Indexed: 12/17/2022] Open
Abstract
Dysregulation of glucose homeostasis leading to metabolic syndrome and type 2 diabetes is the cause of an increasing world health crisis. New intriguing roles have emerged for Rho family GTPases and their Rho guanine nucleotide exchange factor (GEF) activators in the regulation of glucose homeostasis. This review summates the current knowledge, focusing in particular on the roles of Rho GEFs in the processes of glucose-stimulated insulin secretion by pancreatic β cells and insulin-stimulated glucose uptake into skeletal muscle and adipose tissues. We discuss the ten Rho GEFs that are known so far to regulate glucose homeostasis, nine of which are in mammals, and one is in yeast. Among the mammalian Rho GEFs, P-Rex1, Vav2, Vav3, Tiam1, Kalirin and Plekhg4 were shown to mediate the insulin-stimulated translocation of the glucose transporter GLUT4 to the plasma membrane and/or insulin-stimulated glucose uptake in skeletal muscle or adipose tissue. The Rho GEFs P-Rex1, Vav2, Tiam1 and β-PIX were found to control the glucose-stimulated release of insulin by pancreatic β cells. In vivo studies demonstrated the involvement of the Rho GEFs P-Rex2, Vav2, Vav3 and PDZ-RhoGEF in glucose tolerance and/or insulin sensitivity, with deletion of these GEFs either contributing to the development of metabolic syndrome or protecting from it. This research is in its infancy. Considering that over 80 Rho GEFs exist, it is likely that future research will identify more roles for Rho GEFs in glucose homeostasis.
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Affiliation(s)
- Polly A. Machin
- Signalling Programme, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; (P.A.M.); (E.T.)
| | - Elpida Tsonou
- Signalling Programme, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; (P.A.M.); (E.T.)
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Cambridge CB22 3AT, UK;
| | - David C. Hornigold
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Cambridge CB22 3AT, UK;
| | - Heidi C. E. Welch
- Signalling Programme, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; (P.A.M.); (E.T.)
- Correspondence: ; Tel.: +44-(0)1223-496-596
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6
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Legumain is a predictor of all-cause mortality and potential therapeutic target in acute myocardial infarction. Cell Death Dis 2020; 11:1014. [PMID: 33243972 PMCID: PMC7691341 DOI: 10.1038/s41419-020-03211-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 10/28/2020] [Accepted: 11/02/2020] [Indexed: 12/23/2022]
Abstract
The prognostic impact of extracellular matrix (ECM) modulation and its regulatory mechanism post-acute myocardial infarction (AMI), require further clarification. Herein, we explore the predictive role of legumain—which showed the ability in ECM degradation—in an AMI patient cohort and investigate the underlying mechanisms. A total of 212 AMI patients and 323 healthy controls were enrolled in the study. Moreover, AMI was induced in mice by permanent ligation of the left anterior descending artery and fibroblasts were adopted for mechanism analysis. Based on the cut-off value for the receiver-operating characteristics curve, AMI patients were stratified into low (n = 168) and high (n = 44) plasma legumain concentration (PLG) groups. However, PLG was significantly higher in AMI patients than that in the healthy controls (median 5.9 μg/L [interquartile range: 4.2–9.3 μg/L] vs. median 4.4 μg/L [interquartile range: 3.2–6.1 μg/L], P < 0.001). All-cause mortality was significantly higher in the high PLG group compared to that in the low PLG group (median follow-up period, 39.2 months; 31.8% vs. 12.5%; P = 0.002). Multivariate Cox regression analysis showed that high PLG was associated with increased all-cause mortality after adjusting for clinical confounders (HR = 3.1, 95% confidence interval (CI) = 1.4–7.0, P = 0.005). In accordance with the clinical observations, legumain concentration was also increased in peripheral blood, and infarcted cardiac tissue from experimental AMI mice. Pharmacological blockade of legumain with RR-11a, improved cardiac function, decreased cardiac rupture rate, and attenuated left chamber dilation and wall thinning post-AMI. Hence, plasma legumain concentration is of prognostic value in AMI patients. Moreover, legumain aggravates cardiac remodelling through promoting ECM degradation which occurs, at least partially, via activation of the MMP-2 pathway.
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7
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Li JC, Chang X, Chen Y, Li XZ, Zhang XL, Yang SM, Hu CJ, Zhang H. Loss of the Tumor Suppressor HACE1 Contributes to Cancer Progression. Curr Drug Targets 2020; 20:1018-1028. [PMID: 30827236 DOI: 10.2174/1389450120666190227184654] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/20/2019] [Accepted: 02/14/2019] [Indexed: 12/15/2022]
Abstract
HACE1 belongs to the family of HECT domain-containing E3 ligases, which plays an important role in the occurrence, invasion and metastatic process in many human malignancies. HACE1 is a tumor suppressor gene that is reduced in most cancer tissues compared to adjacent normal tissue. The loss or knocking out of HACE1 leads to enhanced tumor growth, invasion, and metastasis; in contrast, the overexpression of HACE1 can inhibit the development of tumors. Hypermethylation reduces the expression of HACE1, thereby promoting tumor development. HACE1 can inhibit the development of inflammation or tumors via the ubiquitination pathway. Therefore, HACE1 may be a potential therapeutic target, providing new strategies for disease prevention and treatment.
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Affiliation(s)
- Jun-Chen Li
- Department of Gastroenterology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China.,Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University (Army Medical University), Chongqing 400037, China
| | - Xing Chang
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University (Army Medical University), Chongqing 400037, China
| | - Yang Chen
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University (Army Medical University), Chongqing 400037, China
| | - Xin-Zhe Li
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University (Army Medical University), Chongqing 400037, China
| | - Xiang-Lian Zhang
- Department of Gastroenterology, The First Affiliated Hospital of Guangxi Medical University, Guangxi 530021, China
| | - Shi-Ming Yang
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University (Army Medical University), Chongqing 400037, China
| | - Chang-Jiang Hu
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University (Army Medical University), Chongqing 400037, China
| | - Hao Zhang
- Department of Gastroenterology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China
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8
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Dysregulation of Rho GTPases in Human Cancers. Cancers (Basel) 2020; 12:cancers12051179. [PMID: 32392742 PMCID: PMC7281333 DOI: 10.3390/cancers12051179] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/24/2020] [Accepted: 04/30/2020] [Indexed: 01/28/2023] Open
Abstract
Rho GTPases play central roles in numerous cellular processes, including cell motility, cell polarity, and cell cycle progression, by regulating actin cytoskeletal dynamics and cell adhesion. Dysregulation of Rho GTPase signaling is observed in a broad range of human cancers, and is associated with cancer development and malignant phenotypes, including metastasis and chemoresistance. Rho GTPase activity is precisely controlled by guanine nucleotide exchange factors, GTPase-activating proteins, and guanine nucleotide dissociation inhibitors. Recent evidence demonstrates that it is also regulated by post-translational modifications, such as phosphorylation, ubiquitination, and sumoylation. Here, we review the current knowledge on the role of Rho GTPases, and the precise mechanisms controlling their activity in the regulation of cancer progression. In addition, we discuss targeting strategies for the development of new drugs to improve cancer therapy.
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9
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The ubiquitin ligase HERC1 regulates cell migration via RAF-dependent regulation of MKK3/p38 signaling. Sci Rep 2020; 10:824. [PMID: 31965002 PMCID: PMC6972752 DOI: 10.1038/s41598-020-57756-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 01/03/2020] [Indexed: 12/12/2022] Open
Abstract
Protein modifications by phosphorylation or ubiquitylation have been selected throughout evolution as efficient regulatory mechanisms of cellular processes. Cell migration is a complex, highly coordinated process where these mechanisms must participate in an integrated manner to transmit signaling during migration. In this study, we show that the ubiquitin ligase HERC1 regulates the p38 signaling pathway, and that this regulation is mediated by the MAPK kinase MKK3. Moreover, we demonstrate a crosstalk between RAF and MKK3/p38 pathways where RAF acts upstream of MKK3. Mechanistically, HERC1 regulates the protein levels of C-RAF and MKK3. Thus, HERC1 ubiquitylates C-RAF, targeting it for proteasomal degradation, and RAF proteins regulate MKK3 mRNA levels. Accordingly, HERC1 knockdown induces C-RAF stabilization and activation of RAF proteins; in turn, this activation increases MKK3, which phosphorylates and activates p38. The importance of these observations is demonstrated by HERC1 regulation of cell migration through regulation of p38 signaling via a RAF-dependent mechanism. Thus, HERC1 plays an essential role as a regulator of crosstalk between RAF/MKK3/p38 signaling pathways during cell migration.
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10
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Chu H, Wang W, Luo W, Zhang W, Cheng Y, Huang J, Wang J, Dai X, Fang S, Chao J. CircHECTD1 mediates pulmonary fibroblast activation via HECTD1. Ther Adv Chronic Dis 2019; 10:2040622319891558. [PMID: 31832126 PMCID: PMC6887829 DOI: 10.1177/2040622319891558] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 11/04/2019] [Indexed: 11/16/2022] Open
Abstract
Background: Circular RNA (circRNA), a new class of noncoding RNA, has been shown to be important in silicosis due to its unique role as a transcription regulator or as a sponge of small RNA regulators. Here, the mechanisms underlying circHECTD1/HECTD1 in fibroblast activation and subsequent fibrosis induced by SiO2 were investigated. Methods: Primary human pulmonary fibroblasts (HPF-a) were utilized, combined with quantitative real-time PCR (qRT-PCR) and fluorescence in situ hybridization (FISH) assays. LC3B-LV-RFP lentivirus was used to evaluate the role of autophagy. The CRISPR/Cas9 system was applied to specifically knock down HECTD1, combined with MTT, BrdU, and migration assays, to explore the functional changes induced by SiO2. Results: After exposure to SiO2, the circHECTD1 level was decreased, which was associated with an increase in HECTD1 in HPF-a cells. SiO2-induced autophagy was reversed by either circHECTD1 overexpression or HECTD1 knockdown in HPF-a cells, with restored SiO2-induced fibroblast activation, proliferation, and migration via downstream autophagy. The lungs of mice exposed to SiO2 confirmed the upregulation of HECTD1 in pulmonary fibroblasts. Conclusions: Our data suggested a link between circHECTD1/HECTD1 and fibroblast activation with subsequent fibrosis induced by SiO2, providing novel insight into the potential of circHECTD1/HECTD1 to be a therapeutic target for silicosis.
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Affiliation(s)
- Han Chu
- Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Wei Wang
- Department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, Jiangsu, China
| | - Wei Luo
- Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Wei Zhang
- Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Yusi Cheng
- Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Jie Huang
- Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Jing Wang
- Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Xiaoniu Dai
- Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu, China
| | - Shencun Fang
- Department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, Jiangsu, China
| | - Jie Chao
- Department of Physiology, School of Medicine, Southeast University, 87 Dingjiaqiao Road, Nanjing, Jiangsu, 210009, China
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11
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Silvestre JG, Baptista IL, Silva WJ, Cruz A, Silva MT, Miyabara EH, Labeit S, Moriscot AS. The E3 ligase MuRF2 plays a key role in the functional capacity of skeletal muscle fibroblasts. ACTA ACUST UNITED AC 2019; 52:e8551. [PMID: 31482977 PMCID: PMC6720025 DOI: 10.1590/1414-431x20198551] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 07/11/2019] [Indexed: 12/13/2022]
Abstract
Fibroblasts are a highly heterogeneous population of cells, being found in a large number of different tissues. These cells produce the extracellular matrix, which is essential to preserve structural integrity of connective tissues. Fibroblasts are frequently engaged in migration and remodeling, exerting traction forces in the extracellular matrix, which is crucial for matrix deposition and wound healing. In addition, previous studies performed on primary myoblasts suggest that the E3 ligase MuRF2 might function as a cytoskeleton adaptor. Here, we hypothesized that MuRF2 also plays a functional role in skeletal muscle fibroblasts. We found that skeletal muscle fibroblasts express MuRF2 and its siRNA knock-down promoted decreased fibroblast migration, cell border accumulation of polymerized actin, and down-regulation of the phospho-Akt expression. Our results indicated that MuRF2 was necessary to maintain the actin cytoskeleton functionality in skeletal muscle fibroblasts via Akt activity and exerted an important role in extracellular matrix remodeling in the skeletal muscle tissue.
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Affiliation(s)
- J G Silvestre
- Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - I L Baptista
- Faculdade de Ciências Aplicadas, UNICAMP, Limeira, SP, Brasil
| | - W J Silva
- Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - A Cruz
- Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - M T Silva
- Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - E H Miyabara
- Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - S Labeit
- Institute for Integrative Pathophysiology, Mannheim Medical University, Faculty for Clinical Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - A S Moriscot
- Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
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12
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Hudson AM, Mannix KM, Gerdes JA, Kottemann MC, Cooley L. Targeted substrate degradation by Kelch controls the actin cytoskeleton during ring canal expansion. Development 2019; 146:dev.169219. [PMID: 30559276 DOI: 10.1242/dev.169219] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 11/27/2018] [Indexed: 11/20/2022]
Abstract
During Drosophila oogenesis, specialized actin-based structures called ring canals form and expand to accommodate growth of the oocyte. Previous work demonstrated that Kelch and Cullin 3 function together in a Cullin 3-RING ubiquitin ligase complex (CRL3Kelch) to organize the ring canal cytoskeleton, presumably by targeting a substrate for proteolysis. Here, we use tandem affinity purification followed by mass spectrometry to identify HtsRC as the CRL3Kelch ring canal substrate. CRISPR-mediated mutagenesis of HtsRC revealed its requirement in the recruitment of the ring canal F-actin cytoskeleton. We present genetic evidence consistent with HtsRC being the CRL3Kelch substrate, as well as biochemical evidence indicating that HtsRC is ubiquitylated and degraded by the proteasome. Finally, we identify a short sequence motif in HtsRC that is necessary for Kelch binding. These findings uncover an unusual mechanism during development wherein a specialized cytoskeletal structure is regulated and remodeled by the ubiquitin-proteasome system.
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Affiliation(s)
- Andrew M Hudson
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Katelynn M Mannix
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Julianne A Gerdes
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Molly C Kottemann
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Lynn Cooley
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA .,Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06520, USA.,Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT 06520, USA
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13
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Ma TJ, Zhang ZW, Lu YL, Zhang YY, Tao DC, Liu YQ, Ma YX. CLOCK and BMAL1 stabilize and activate RHOA to promote F-actin formation in cancer cells. Exp Mol Med 2018; 50:1-15. [PMID: 30287810 PMCID: PMC6172197 DOI: 10.1038/s12276-018-0156-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 06/20/2018] [Accepted: 06/22/2018] [Indexed: 02/05/2023] Open
Abstract
Circadian genes control most of the physiological functions in cancer cells, including cell proliferation, migration, and invasion. The CLOCK and BMAL1 complex plays a central role in circadian rhythms. Previous studies have shown that circadian genes may act as oncogenes or tumor-suppressor genes. In addition, F-actin, regulated by RHOA, has been shown to participate in tumor progression. However, the roles of the CLOCK and BMAL1 genes in the regulation of tumor progression via the RHOA-ROCK-CFL pathway remain largely unclear. Here we first indicate that the rearrangement of F-actin is regulated by CLOCK and BMAL1. We found that CLOCK and BMAL1 can upregulate RHOA expression by inhibiting CUL3-mediated ubiquitination and activate RHOA by reducing the interaction between RHOA and RhoGDI. Consequently, CLOCK and BMAL1 control the expression of the components of the RHOA-ROCK-CFL pathway, which alters the dynamics of F-actin/G-actin turnover and promotes cancer cell proliferation, migration, and invasion. In conclusion, our research proposes a novel insight into the role of CLOCK and BMAL1 in tumor cells.
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Affiliation(s)
- Teng-Jiao Ma
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Zhi-Wei Zhang
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Yi-Lu Lu
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Ying-Ying Zhang
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Da-Chang Tao
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Yun-Qiang Liu
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Yong-Xin Ma
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China.
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14
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Nichols AEC, Settlage RE, Werre SR, Dahlgren LA. Novel roles for scleraxis in regulating adult tenocyte function. BMC Cell Biol 2018; 19:14. [PMID: 30086712 PMCID: PMC6081934 DOI: 10.1186/s12860-018-0166-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 07/30/2018] [Indexed: 12/15/2022] Open
Abstract
Background Tendinopathies are common and difficult to resolve due to the formation of scar tissue that reduces the mechanical integrity of the tissue, leading to frequent reinjury. Tenocytes respond to both excessive loading and unloading by producing pro-inflammatory mediators, suggesting that these cells are actively involved in the development of tendon degeneration. The transcription factor scleraxis (Scx) is required for the development of force-transmitting tendon during development and for mechanically stimulated tenogenesis of stem cells, but its function in adult tenocytes is less well-defined. The aim of this study was to further define the role of Scx in mediating the adult tenocyte mechanoresponse. Results Equine tenocytes exposed to siRNA targeting Scx or a control siRNA were maintained under cyclic mechanical strain before being submitted for RNA-seq analysis. Focal adhesions and extracellular matrix-receptor interaction were among the top gene networks downregulated in Scx knockdown tenocytes. Correspondingly, tenocytes exposed to Scx siRNA were significantly softer, with longer vinculin-containing focal adhesions, and an impaired ability to migrate on soft surfaces. Other pathways affected by Scx knockdown included increased oxidative phosphorylation and diseases caused by endoplasmic reticular stress, pointing to a larger role for Scx in maintaining tenocyte homeostasis. Conclusions Our study identifies several novel roles for Scx in adult tenocytes, which suggest that Scx facilitates mechanosensing by regulating the expression of several mechanosensitive focal adhesion proteins. Furthermore, we identified a number of other pathways and targets affected by Scx knockdown that have the potential to elucidate the role that tenocytes may play in the development of degenerative tendinopathy. Electronic supplementary material The online version of this article (10.1186/s12860-018-0166-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anne E C Nichols
- Department of Large Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, 205 Duck Pond Drive, Blacksburg, VA, 24061-0442, USA
| | - Robert E Settlage
- Advanced Research Computing, Virginia Biocomplexity Institute, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Stephen R Werre
- Laboratory for Study Design and Statistical Analysis, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, 24061, USA
| | - Linda A Dahlgren
- Department of Large Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, 205 Duck Pond Drive, Blacksburg, VA, 24061-0442, USA.
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15
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Abstract
Excessive proliferation and migration of fibroblasts contribute to pulmonary fibrosis in silicosis, and both epithelial cells and endothelial cells participate in the accumulation of fibroblasts via the epithelial–mesenchymal transition (EMT) and the endothelial–mesenchymal transition (EndMT), respectively. A mouse endothelial cell line (MML1) was exposed to silicon dioxide (SiO2, 50 μg/cm2), and immunofluorescence and western blot analyses were performed to evaluate levels of specific endothelial and mesenchymal markers and to elucidate the mechanisms by which SiO2 induces the EndMT. Functional changes were evaluated by analyzing cell migration and proliferation. The mRNA and circular RNA (circRNA) levels were measured using qPCR and fluorescent in situ hybridization (FISH). Lung tissue samples from both Tie2-GFP mice exposed to SiO2 and silicosis patients were applied to confirm the observations from in vitro experiments. Based on the results from the current study, SiO2 increased the expression of mesenchymal markers (type I collagen (COL1A1), type III collagen (COL3A1) and alpha smooth muscle actin (α-SMA/Acta2)) and decreased the expression of endothelial markers (vascular endothelial cadherin (VE-Cad/Cdh 5) and platelet endothelial cell adhesion molecule-1 (PECAM1)), indicating the occurrence of the EndMT in response to SiO2 exposure both in vivo and in vitro. SiO2 concomitantly increased circHECTD1 expression, which, in turn, inhibited HECTD1 protein expression. SiO2-induced increases in cell proliferation, migration, and changes in marker levels were restored by either a small interfering RNA (siRNA) targeting circHECTD1 or overexpression of HECTD1 via the CRISPR/Cas9 system, confirming the involvement of the circHECTD1/HECTD1 pathway in the EndMT. Moreover, tissue samples from SiO2-exposed mice and silicosis patients confirmed the EndMT and change in HECTD1 expression. Our findings reveal a potentially new function for the circHECTD1/HECTD1 pathway and suggest a possible mechanism of fibrosis in patients with pulmonary silicosis.
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16
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Bai Y, Zhang Y, Han B, Yang L, Chen X, Huang R, Wu F, Chao J, Liu P, Hu G, Zhang JH, Yao H. Circular RNA DLGAP4 Ameliorates Ischemic Stroke Outcomes by Targeting miR-143 to Regulate Endothelial-Mesenchymal Transition Associated with Blood-Brain Barrier Integrity. J Neurosci 2018; 38:32-50. [PMID: 29114076 PMCID: PMC6705810 DOI: 10.1523/jneurosci.1348-17.2017] [Citation(s) in RCA: 288] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 10/24/2017] [Accepted: 10/29/2017] [Indexed: 01/01/2023] Open
Abstract
Circular RNAs (circRNAs) are highly expressed in the CNS and regulate physiological and pathophysiological processes. However, the potential role of circRNAs in stroke remains largely unknown. Here, we show that the circRNA DLGAP4 (circDLGAP4) functions as an endogenous microRNA-143 (miR-143) sponge to inhibit miR-143 activity, resulting in the inhibition of homologous to the E6-AP C-terminal domain E3 ubiquitin protein ligase 1 expression. circDLGAP4 levels were significantly decreased in the plasma of acute ischemic stroke patients (13 females and 13 males) and in a mouse stroke model. Upregulation of circDLGAP4 expression significantly attenuated neurological deficits and decreased infarct areas and blood-brain barrier damage in the transient middle cerebral artery occlusion mouse stroke model. Endothelial-mesenchymal transition contributes to blood-brain barrier disruption and circDLGAP4 overexpression significantly inhibited endothelial-mesenchymal transition by regulating tight junction protein and mesenchymal cell marker expression. Together, the results of our study are illustrative of the involvement of circDLGAP4 and its coupling mechanism in cerebral ischemia, providing translational evidence that circDLGAP4 serves as a novel therapeutic target for acute cerebrovascular protection.SIGNIFICANCE STATEMENT Circular RNAs (circRNAs) are involved in the regulation of physiological and pathophysiological processes. However, whether circRNAs are involved in ischemic injury, particularly cerebrovascular disorders, remains largely unknown. Here, we demonstrate a critical role for circular RNA DLGAP4 (circDLGAP4), a novel circular RNA originally identified as a sponge for microRNA-143 (miR-143), in ischemic stroke outcomes. Overexpression of circDLGAP4 significantly attenuated neurological deficits and decreased infarct areas and blood-brain barrier damage in the transient middle cerebral artery occlusion mouse stroke model. To our knowledge, this is the first report describing the efficacy of circRNA injection in an ischemic stroke model. Our investigation suggests that circDLGAP4 may serve as a novel therapeutic target for acute ischemic injury.
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Affiliation(s)
- Ying Bai
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Yuan Zhang
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Bing Han
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Li Yang
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xufeng Chen
- Emergency Department, Jiangsu Province Hospital, Nanjing 210029, China
| | - Rongrong Huang
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Fangfang Wu
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Jie Chao
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Pei Liu
- Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing 210009, China
| | - Gang Hu
- Jiangsu Key Laboratory of Neurodegeneration, Department of Pharmacology, Nanjing Medical University, Nanjing 210029, China
| | - John H Zhang
- Department of Anesthesiology, School of Medicine, Loma Linda University, Loma Linda, California 92354, and
| | - Honghong Yao
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing 210009, China,
- Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China
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17
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Zhou Z, Jiang R, Yang X, Guo H, Fang S, Zhang Y, Cheng Y, Wang J, Yao H, Chao J. circRNA Mediates Silica-Induced Macrophage Activation Via HECTD1/ZC3H12A-Dependent Ubiquitination. Am J Cancer Res 2018; 8:575-592. [PMID: 29290828 PMCID: PMC5743568 DOI: 10.7150/thno.21648] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 10/12/2017] [Indexed: 12/16/2022] Open
Abstract
Rationale: Phagocytosis of silicon dioxide (SiO2) into lung cells causes an inflammatory cascade that results in fibroblast proliferation and migration, followed by fibrosis. Circular RNAs (circRNAs) are a subclass of non-coding RNAs detected within mammalian cells; however, researchers have not determined whether circRNAs are involved in the pathophysiological process of silicosis. The upstream molecular mechanisms and functional effects on cell apoptosis, proliferation and migration were investigated to elucidate the role of circRNAs in SiO2-induced inflammation in pulmonary macrophages. Methods: Primary cultures of alveolar macrophages from healthy donors and patients as well as the RAW264.7 macrophage cell line were used to explore the functions of circHECTD1 (HECT domain E3 ubiquitin protein ligase 1) in macrophage activation. Results: The results of the experiments indicated that 1) SiO2 concomitantly decreased circHECTD1 levels and increased HECTD1 protein expression; 2) circHECTD1 and HECTD1 were involved in SiO2-induced macrophage activation via ubiquitination; and 3) SiO2-activated macrophages promoted fibroblast proliferation and migration via the circHECTD1/HECTD1 pathway. Tissue samples from silicosis patients confirmed the upregulation of HECTD1. Conclusions: Our study elucidated a link between SiO2-induced macrophage activation and the circHECTD1/HECTD1 pathway, thereby providing new insight into the potential use of HECTD1 in the development of novel therapeutic strategies for treating silicosis.
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18
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The molecular basis of talin2's high affinity toward β1-integrin. Sci Rep 2017; 7:41989. [PMID: 28155884 PMCID: PMC5290461 DOI: 10.1038/srep41989] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 01/04/2017] [Indexed: 01/16/2023] Open
Abstract
Talin interacts with β-integrin tails and actin to control integrin activation, thus regulating focal adhesion dynamics and cell migration. There are two talin genes, Tln1 and Tln2, which encode talin1 and talin2, and it is generally believed that talin2 functions redundantly with talin1. However, we show here that talin2 has a higher affinity to β1-integrin tails than talin1. Mutation of talin2 S339 to leucine, which can cause Fifth Finger Camptodactyly, a human genetic disease, completely disrupted its binding to β–integrin tails. Also, substitution of talin1 C336 with Ser enhanced the affinity of talin1, whereas substitution of talin2 S339 with Cys diminished that of talin2. Further computational modeling analysis shows that talin2 S339 formed a hydrogen bond with E353, which is critical for inducing key hydrogen bonds between talin2 N326 and β1-integrin R760, and between talin2 K327 and β1-integrin D759. Mutation at any of these residues significantly diminished the interaction of talin2 with β1- integrin tails. These hydrogen bonds were not observed in talin1/β1-integrin, but did exist in talin1C336S/β1-integrin complex. These results suggest that talin2 S339 forms a hydrogen bond with E353 to mediate its high affinity to β1-integrin.
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19
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Vlahakis A, Debnath J. The Interconnections between Autophagy and Integrin-Mediated Cell Adhesion. J Mol Biol 2016; 429:515-530. [PMID: 27932295 DOI: 10.1016/j.jmb.2016.11.027] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 11/27/2016] [Accepted: 11/29/2016] [Indexed: 12/25/2022]
Abstract
Autophagy is a cellular degradation process integral for promoting cellular adaptation during metabolic stress while also functioning as a cellular homeostatic mechanism. Mounting evidence also demonstrates that autophagy is induced upon loss of integrin-mediated cell attachments to the surrounding extracellular matrix (ECM). Analogous to its established cytoprotective role during nutrient starvation, autophagy protects cells from detachment-induced cell death, termed anoikis. Here, we review the significance of autophagy as an anoikis resistance pathway, focusing on the intracellular signals associated with integrins that modulate the autophagy response and dictate the balance between cell death and survival following loss of cell-matrix contact. In addition, we highlight recent studies demonstrating that autophagy functions in the upstream regulation of integrin-mediated cell adhesion via the control of focal adhesion remodeling, and discuss how these emerging interconnections between integrin-mediated adhesion pathways and autophagy influence cancer progression and metastasis.
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Affiliation(s)
- Ariadne Vlahakis
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA.
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20
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Szasz T, Webb RC. Rho-Mancing to Sensitize Calcium Signaling for Contraction in the Vasculature: Role of Rho Kinase. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2016; 78:303-322. [PMID: 28212799 DOI: 10.1016/bs.apha.2016.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Vascular smooth muscle contraction is an important physiological process contributing to cardiovascular homeostasis. The principal determinant of smooth muscle contraction is the intracellular free Ca2+ concentration, and phosphorylation of myosin light chain (MLC) by activated myosin light chain kinase (MLCK) in response to increased Ca2+ is the main pathway by which vasoconstrictor stimuli induce crossbridge cycling of myosin and actin filaments. A secondary pathway for vascular smooth muscle contraction that is not directly dependent on Ca2+ concentration, but rather mediating Ca2+ sensitization, is the RhoA/Rho kinase pathway. In response to contractile stimuli, the small GTPase RhoA activates its downstream effector Rho kinase which, in turn, promotes contraction via myosin light chain phosphatase (MLCP) inhibition. RhoA/Rho kinase-mediated MLCP inhibition occurs mainly by phosphorylation and inhibition of MYPT1, the regulatory subunit of MLCP, or by CPI-17-mediated inhibition of the catalytic subunit of MLCP. In this review, we describe the molecular mechanisms underlying the pivotal role exerted by Rho kinase on vascular smooth muscle contraction and discuss the main regulatory pathways for its activity.
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Affiliation(s)
- T Szasz
- Augusta University, Augusta, GA, United States.
| | - R C Webb
- Augusta University, Augusta, GA, United States
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21
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Gao ZF, Wu YN, Bai ZT, Zhang L, Zhou Q, Li X. Tumor-suppressive role of HACE1 in hepatocellular carcinoma and its clinical significance. Oncol Rep 2016; 36:3427-3435. [PMID: 27805249 DOI: 10.3892/or.2016.5205] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 04/13/2016] [Indexed: 11/05/2022] Open
Abstract
An increasing body of evidence suggests that downregulation or deletion of HECT domain and ankyrin repeat containing E3 ubiquitin protein ligase 1 (HACE1) gene plays an important role in the occurrence, invasion and metastasis process in many human malignancies and is closely related to prognosis. However, sparse evidence exists concerning the precise function and clinical significance of HACE1 in hepatocellular carcinoma (HCC). In the present study, we investigated the expression pattern of HACE1 in HCC tissues and cell lines, and determined the potential functions of HACE1 in HCC cell lines and evaluated the relationships between HACE1 expression and clinicopathological characteristics. Protein and mRNA expression levels of HACE1 in human HCC tissues and cell lines were examined by western blot analysis, quantitative real‑time polymerase chain reaction and immunohistochemical (IHC) analyses. IHC was used to analyze the correlations between HACE1 expression and clinicopathological features. HACE1 was upregulated in SMCC7721 cells by transfection with pcDNA3.1-HACE1 and Huh7 cells were transfected with siRNA targeting HACE1 for downregulation. Cell Counting Κit-8, Transwell and wound healing assays were performed to investigate the effects of the overexpression and knockdown of HACE1 on cellular proliferation and migration. The results revealed that HACE1 expression was lower in the HCC tissues and cell lines at the mRNA and protein levels compared to levels noted in the matched non‑tumor tissues and the normal liver cell line L02. Knockdown of HACE1 in Huh7 cells accelerated cell proliferation and migration (P<0.05), and overexpression of HACE1 in SMCC7721 cells was found to decrease the capacity for proliferation and migration (P<0.01). The results of IHC suggested that the HACE1 expression level was closely related to the serum AFP level, tumor differentiation and vascular invasion (P<0.05). Patients with low HACE1 expression levels exhibited poorer overall survival and HACE1 was found to be an independent prognostic factor for survival. In conclusion, as a tumor suppressor, HACE1 may be a valuable prognostic biomarker and potential therapeutic target for HCC treatment.
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Affiliation(s)
- Zeng-Fa Gao
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu 730000, P.R. China
| | - Yong-Na Wu
- Gansu Province Key Laboratory of Biotherapy and Regenerative Medicine, Lanzhou, Gansu 730000, P.R. China
| | - Zhong-Tian Bai
- The Second Department of General Surgery, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China
| | - Lei Zhang
- The Second Department of General Surgery, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China
| | - Qi Zhou
- Department of Pathology, The First Hospital of Lanzhou University (The Branch Hospital of Donggang), Lanzhou, Gansu 730000, P.R. China
| | - Xun Li
- Gansu Province Key Laboratory of Biotherapy and Regenerative Medicine, Lanzhou, Gansu 730000, P.R. China
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22
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Jafari N, Zheng Q, Li L, Li W, Qi L, Xiao J, Gao T, Huang C. p70S6K1 (S6K1)-mediated Phosphorylation Regulates Phosphatidylinositol 4-Phosphate 5-Kinase Type I γ Degradation and Cell Invasion. J Biol Chem 2016; 291:25729-25741. [PMID: 27780861 DOI: 10.1074/jbc.m116.742742] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 10/22/2016] [Indexed: 11/06/2022] Open
Abstract
Phosphatidylinositol 4-phosphate 5-kinase type I γ (PIPKIγ90) ubiquitination and subsequent degradation regulate focal adhesion assembly, cell migration, and invasion. However, it is unknown how upstream signals control PIPKIγ90 ubiquitination or degradation. Here we show that p70S6K1 (S6K1), a downstream target of mechanistic target of rapamycin (mTOR), phosphorylates PIPKIγ90 at Thr-553 and Ser-555 and that S6K1-mediated PIPKIγ90 phosphorylation is essential for cell migration and invasion. Moreover, PIPKIγ90 phosphorylation is required for the development of focal adhesions and invadopodia, key machineries for cell migration and invasion. Surprisingly, substitution of Thr-553 and Ser-555 with Ala promoted PIPKIγ90 ubiquitination but enhanced the stability of PIPKIγ90, and depletion of S6K1 also enhanced the stability of PIPKIγ90, indicating that PIPKIγ90 ubiquitination alone is insufficient for its degradation. These data suggest that S6K1-mediated PIPKIγ90 phosphorylation regulates cell migration and invasion by controlling PIPKIγ90 degradation.
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Affiliation(s)
- Naser Jafari
- From the Markey Cancer Center and.,the Veterans Affairs Medical Center, Lexington, Kentucky 40502
| | | | | | - Wei Li
- From the Markey Cancer Center and
| | - Lei Qi
- From the Markey Cancer Center and
| | | | | | - Cai Huang
- From the Markey Cancer Center and .,the Veterans Affairs Medical Center, Lexington, Kentucky 40502.,the Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky 40506 and
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23
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Abstract
Rho GTPases regulate cytoskeletal and cell adhesion dynamics and thereby coordinate a wide range of cellular processes, including cell migration, cell polarity and cell cycle progression. Most Rho GTPases cycle between a GTP-bound active conformation and a GDP-bound inactive conformation to regulate their ability to activate effector proteins and to elicit cellular responses. However, it has become apparent that Rho GTPases are regulated by post-translational modifications and the formation of specific protein complexes, in addition to GTP-GDP cycling. The canonical regulators of Rho GTPases - guanine nucleotide exchange factors, GTPase-activating proteins and guanine nucleotide dissociation inhibitors - are regulated similarly, creating a complex network of interactions to determine the precise spatiotemporal activation of Rho GTPases.
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Affiliation(s)
- Richard G Hodge
- Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK
| | - Anne J Ridley
- Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK
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24
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Zhang W, Wu KP, Sartori MA, Kamadurai HB, Ordureau A, Jiang C, Mercredi PY, Murchie R, Hu J, Persaud A, Mukherjee M, Li N, Doye A, Walker JR, Sheng Y, Hao Z, Li Y, Brown KR, Lemichez E, Chen J, Tong Y, Harper JW, Moffat J, Rotin D, Schulman BA, Sidhu SS. System-Wide Modulation of HECT E3 Ligases with Selective Ubiquitin Variant Probes. Mol Cell 2016; 62:121-36. [PMID: 26949039 DOI: 10.1016/j.molcel.2016.02.005] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 01/23/2016] [Accepted: 02/03/2016] [Indexed: 11/20/2022]
Abstract
HECT-family E3 ligases ubiquitinate protein substrates to control virtually every eukaryotic process and are misregulated in numerous diseases. Nonetheless, understanding of HECT E3s is limited by a paucity of selective and potent modulators. To overcome this challenge, we systematically developed ubiquitin variants (UbVs) that inhibit or activate HECT E3s. Structural analysis of 6 HECT-UbV complexes revealed UbV inhibitors hijacking the E2-binding site and activators occupying a ubiquitin-binding exosite. Furthermore, UbVs unearthed distinct regulation mechanisms among NEDD4 subfamily HECTs and proved useful for modulating therapeutically relevant targets of HECT E3s in cells and intestinal organoids, and in a genetic screen that identified a role for NEDD4L in regulating cell migration. Our work demonstrates versatility of UbVs for modulating activity across an E3 family, defines mechanisms and provides a toolkit for probing functions of HECT E3s, and establishes a general strategy for systematic development of modulators targeting families of signaling proteins.
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Affiliation(s)
- Wei Zhang
- Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, 160 College Street, Toronto, ON M5S3E1, Canada
| | - Kuen-Phon Wu
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Maria A Sartori
- Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, 160 College Street, Toronto, ON M5S3E1, Canada
| | - Hari B Kamadurai
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Alban Ordureau
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Chong Jiang
- Program in Cell Biology, Hospital for Sick Children, and Department of Biochemistry, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Peter Y Mercredi
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Ryan Murchie
- Program in Cell Biology, Hospital for Sick Children, and Department of Biochemistry, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Jicheng Hu
- Structural Genomics Consortium, University of Toronto, Toronto, ON M5G1L7, Canada
| | - Avinash Persaud
- Program in Cell Biology, Hospital for Sick Children, and Department of Biochemistry, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Manjeet Mukherjee
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Nan Li
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030, USA
| | - Anne Doye
- Inserm U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Equipe Labellisée La Ligue Contre Le Cancer, Université de Nice-Sophia Antipolis, 151 Route St Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex, France
| | - John R Walker
- Structural Genomics Consortium, University of Toronto, Toronto, ON M5G1L7, Canada
| | - Yi Sheng
- Department of Biology, York University, Toronto, Ontario M3J1P3, Canada
| | - Zhenyue Hao
- Campbell Family Cancer Research Institute, University Health Network, Toronto, ON M5G2C1, Canada
| | - Yanjun Li
- Structural Genomics Consortium, University of Toronto, Toronto, ON M5G1L7, Canada
| | - Kevin R Brown
- Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, 160 College Street, Toronto, ON M5S3E1, Canada
| | - Emmanuel Lemichez
- Inserm U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Equipe Labellisée La Ligue Contre Le Cancer, Université de Nice-Sophia Antipolis, 151 Route St Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex, France
| | - Junjie Chen
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030, USA
| | - Yufeng Tong
- Structural Genomics Consortium, University of Toronto, Toronto, ON M5G1L7, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON M5G1L7, Canada
| | - J Wade Harper
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Jason Moffat
- Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, 160 College Street, Toronto, ON M5S3E1, Canada; Department of Molecular Genetics, University of Toronto, 1 King's College Cir, Toronto, ON M5S1A8, Canada
| | - Daniela Rotin
- Program in Cell Biology, Hospital for Sick Children, and Department of Biochemistry, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Brenda A Schulman
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Sachdev S Sidhu
- Donnelly Centre for Cellular and Biomolecular Research, Banting and Best Department of Medical Research, University of Toronto, 160 College Street, Toronto, ON M5S3E1, Canada; Department of Molecular Genetics, University of Toronto, 1 King's College Cir, Toronto, ON M5S1A8, Canada.
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25
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Kenific CM, Stehbens SJ, Goldsmith J, Leidal AM, Faure N, Ye J, Wittmann T, Debnath J. NBR1 enables autophagy-dependent focal adhesion turnover. J Cell Biol 2016; 212:577-90. [PMID: 26903539 PMCID: PMC4772495 DOI: 10.1083/jcb.201503075] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 01/19/2016] [Indexed: 12/21/2022] Open
Abstract
The selective autophagy cargo receptor NBR1 enhances the disassembly of cell-matrix focal adhesions during cell migration. Autophagy is a catabolic pathway involving the sequestration of cellular contents into a double-membrane vesicle, the autophagosome. Although recent studies have demonstrated that autophagy supports cell migration, the underlying mechanisms remain unknown. Using live-cell imaging, we uncover that autophagy promotes optimal migratory rate and facilitates the dynamic assembly and disassembly of cell-matrix focal adhesions (FAs), which is essential for efficient motility. Additionally, our studies reveal that autophagosomes associate with FAs primarily during disassembly, suggesting autophagy locally facilitates the destabilization of cell-matrix contact sites. Furthermore, we identify the selective autophagy cargo receptor neighbor of BRCA1 (NBR1) as a key mediator of autophagy-dependent FA remodeling. NBR1 depletion impairs FA turnover and decreases targeting of autophagosomes to FAs, whereas ectopic expression of autophagy-competent, but not autophagy-defective, NBR1 enhances FA disassembly and reduces FA lifetime during migration. Our findings provide mechanistic insight into how autophagy promotes migration by revealing a requirement for NBR1-mediated selective autophagy in enabling FA disassembly in motile cells.
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Affiliation(s)
- Candia M Kenific
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143 Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Samantha J Stehbens
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143
| | - Juliet Goldsmith
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143 Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Andrew M Leidal
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Nathalie Faure
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Jordan Ye
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Torsten Wittmann
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
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26
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Conte F, Oti M, Dixon J, Carels CEL, Rubini M, Zhou H. Systematic analysis of copy number variants of a large cohort of orofacial cleft patients identifies candidate genes for orofacial clefts. Hum Genet 2015; 135:41-59. [PMID: 26561393 PMCID: PMC4698300 DOI: 10.1007/s00439-015-1606-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 10/15/2015] [Indexed: 12/16/2022]
Abstract
Orofacial clefts (OFCs) represent a large fraction of human birth defects and are one of the most common phenotypes affected by large copy number variants (CNVs). Due to the limited number of CNV patients in individual centers, CNV analyses of a large number of OFC patients are challenging. The present study analyzed 249 genomic deletions and 226 duplications from a cohort of 312 OFC patients reported in two publicly accessible databases of chromosome imbalance and phenotype in humans, DECIPHER and ECARUCA. Genomic regions deleted or duplicated in multiple patients were identified, and genes in these overlapping CNVs were prioritized based on the number of genes encompassed by the region and gene expression in embryonic mouse palate. Our analyses of these overlapping CNVs identified two genes known to be causative for human OFCs, SATB2 and MEIS2, and 12 genes (DGCR6, FGF2, FRZB, LETM1, MAPK3, SPRY1, THBS1, TSHZ1, TTC28, TULP4, WHSC1, WHSC2) that are associated with OFC or orofacial development. Additionally, we report 34 deleted and 24 duplicated genes that have not previously been associated with OFCs but are associated with the BMP, MAPK and RAC1 pathways. Statistical analyses show that the high number of overlapping CNVs is not due to random occurrence. The identified genes are not located in highly variable genomic regions in healthy populations and are significantly enriched for genes that are involved in orofacial development. In summary, we report a CNV analysis pipeline of a large cohort of OFC patients and identify novel candidate OFC genes.
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Affiliation(s)
- Federica Conte
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands.,Medical Genetic Unit, Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy
| | - Martin Oti
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Jill Dixon
- Faculty of Medical and Human Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Carine E L Carels
- Department of Orthodontics and Craniofacial Biology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Michele Rubini
- Medical Genetic Unit, Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy.
| | - Huiqing Zhou
- Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands. .,Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
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27
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McGraw KL, Basiorka AA, Johnson JO, Clark J, Caceres G, Padron E, Heaton R, Ozawa Y, Wei S, Sokol L, List AF. Lenalidomide induces lipid raft assembly to enhance erythropoietin receptor signaling in myelodysplastic syndrome progenitors. PLoS One 2014; 9:e114249. [PMID: 25469886 PMCID: PMC4254997 DOI: 10.1371/journal.pone.0114249] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 11/05/2014] [Indexed: 02/06/2023] Open
Abstract
Anemia remains the principal management challenge for patients with lower risk Myelodysplastic Syndromes (MDS). Despite appropriate cytokine production and cellular receptor display, erythropoietin receptor (EpoR) signaling is impaired. We reported that EpoR signaling is dependent upon receptor localization within lipid raft microdomains, and that disruption of raft integrity abolishes signaling capacity. Here, we show that MDS erythroid progenitors display markedly diminished raft assembly and smaller raft aggregates compared to normal controls (p = 0.005, raft number; p = 0.023, raft size). Because lenalidomide triggers raft coalescence in T-lymphocytes promoting immune synapse formation, we assessed effects of lenalidomide on raft assembly in MDS erythroid precursors and UT7 cells. Lenalidomide treatment rapidly induced lipid raft formation accompanied by EpoR recruitment into raft fractions together with STAT5, JAK2, and Lyn kinase. The JAK2 phosphatase, CD45, a key negative regulator of EpoR signaling, was displaced from raft fractions. Lenalidomide treatment prior to Epo stimulation enhanced both JAK2 and STAT5 phosphorylation in UT7 and primary MDS erythroid progenitors, accompanied by increased STAT5 DNA binding in UT7 cells, and increased erythroid colony forming capacity in both UT7 and primary cells. Raft induction was associated with F-actin polymerization, which was blocked by Rho kinase inhibition. These data indicate that deficient raft integrity impairs EpoR signaling, and provides a novel strategy to enhance EpoR signal fidelity in non-del(5q) MDS.
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Affiliation(s)
- Kathy L. McGraw
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612, United States of America
| | - Ashley A. Basiorka
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center-Cancer Biology Ph.D. Program, University of South Florida, 12902 Magnolia Drive, Tampa, FL, 33612, United States of America
| | - Joseph O. Johnson
- Analytic Microscopy Core Facility, H. Lee Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL, 33612, United States of America
| | - Justine Clark
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612, United States of America
| | - Gisela Caceres
- Morsani Molecular Diagnostic Laboratory, H. Lee Moffitt Cancer Center, 10902 N. McKinley Drive, Tampa, FL, 33612, United States of America
| | - Eric Padron
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612, United States of America
| | - Ruth Heaton
- Department of Pathology, University of Arizona, 1501 N Campbell Ave, Tucson, AZ, 85724, United States of America
| | - Yukiyasu Ozawa
- Department of Hematology, Japanese Red Cross Nagoya First Hospital, 3-35 Michishita-cho, Nakamura-ku, Aichi, 453-8511, Japan
| | - Sheng Wei
- Department of Immunology, H. Lee Moffitt Cancer Center, 12902 Magnolia Drive Tampa, FL, 33612, United States of America
| | - Lubomir Sokol
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612, United States of America
| | - Alan F. List
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612, United States of America
- * E-mail:
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