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Strandberg H, Hagströmer CJ, Werin B, Wendler M, Johanson U, Törnroth-Horsefield S. Structural Basis for the Interaction between the Ezrin FERM-Domain and Human Aquaporins. Int J Mol Sci 2024; 25:7672. [PMID: 39062914 PMCID: PMC11277499 DOI: 10.3390/ijms25147672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Revised: 07/08/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024] Open
Abstract
The Ezrin/Radixin/Moesin (ERM) family of proteins act as cross-linkers between the plasma membrane and the actin cytoskeleton. This mechanism plays an essential role in processes related to membrane remodeling and organization, such as cell polarization, morphogenesis and adhesion, as well as in membrane protein trafficking and signaling pathways. For several human aquaporin (AQP) isoforms, an interaction between the ezrin band Four-point-one, Ezrin, Radixin, Moesin (FERM)-domain and the AQP C-terminus has been demonstrated, and this is believed to be important for AQP localization in the plasma membrane. Here, we investigate the structural basis for the interaction between ezrin and two human AQPs: AQP2 and AQP5. Using microscale thermophoresis, we show that full-length AQP2 and AQP5 as well as peptides corresponding to their C-termini interact with the ezrin FERM-domain with affinities in the low micromolar range. Modelling of the AQP2 and AQP5 FERM complexes using ColabFold reveals a common mode of binding in which the proximal and distal parts of the AQP C-termini bind simultaneously to distinct binding sites of FERM. While the interaction at each site closely resembles other FERM-complexes, the concurrent interaction with both sites has only been observed in the complex between moesin and its C-terminus which causes auto-inhibition. The proposed interaction between AQP2/AQP5 and FERM thus represents a novel binding mode for extrinsic ERM-interacting partners.
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Affiliation(s)
| | | | | | | | | | - Susanna Törnroth-Horsefield
- Department of Biochemistry and Structural Biology, Lund University, 221 00 Lund, Sweden; (H.S.); (C.J.H.); (B.W.); (M.W.); (U.J.)
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Qiao J, Tan Y, Liu H, Yang B, Zhang Q, Liu Q, Sun W, Li Z, Wang Q, Feng W, Yang S, Cui L. Histone H3K18 and Ezrin Lactylation Promote Renal Dysfunction in Sepsis-Associated Acute Kidney Injury. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2307216. [PMID: 38767134 PMCID: PMC11267308 DOI: 10.1002/advs.202307216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 04/29/2024] [Indexed: 05/22/2024]
Abstract
Histone lactylation is a metabolic stress-related histone modification. However, the role of histone lactylation in the development of sepsis-associated acute kidney injury (SA-AKI) remains unclear. Here, histone H3K18 lactylation (H3K18la) is elevated in SA-AKI, which is reported in this study. Furthermore, this lactate-dependent histone modification is enriched at the promoter of Ras homolog gene family member A (RhoA) and positively correlated with the transcription. Correction of abnormal lactate levels resulted in a reversal of abnormal histone lactylation at the promoter of RhoA. Examination of related mechanism revealed that histone lactylation promoted the RhoA/Rho-associated protein kinase (ROCK) /Ezrin signaling, the activation of nuclear factor-κB (NF-κB), inflammation, cell apoptosis, and aggravated renal dysfunction. In addition, Ezrin can undergo lactylation modification. Multiple lactylation sites are identified in Ezrin and confirmed that lactylation mainly occurred at the K263 site. The role of histone lactylation is revealed in SA-AKI and reportes a novel post-translational modification in Ezrin. Its potential role in regulating inflammatory metabolic adaptation of renal proximal tubule epithelial cells is also elucidated. The results provide novel insights into the epigenetic regulation of the onset of SA-AKI.
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Affiliation(s)
- Jiao Qiao
- Institute of Medical TechnologyPeking University Health Science CenterBeijing100191China
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Yuan Tan
- Institute of Medical TechnologyPeking University Health Science CenterBeijing100191China
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Hongchao Liu
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Boxin Yang
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Qian Zhang
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Qi Liu
- Institute of Medical TechnologyPeking University Health Science CenterBeijing100191China
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Wenyuan Sun
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Zhongxin Li
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Qingchen Wang
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Weimin Feng
- Institute of Medical TechnologyPeking University Health Science CenterBeijing100191China
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Shuo Yang
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
| | - Liyan Cui
- Institute of Medical TechnologyPeking University Health Science CenterBeijing100191China
- Department of Laboratory MedicinePeking University Third HospitalBeijing100191China
- Core Unit of National Clinical Research Center for Laboratory MedicinePeking University Third HospitalBeijing100191China
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3
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Chen L, Qian Z, Zheng Y, Zhang J, Sun J, Zhou C, Xiao H. Structural analysis of PTPN21 reveals a dominant-negative effect of the FERM domain on its phosphatase activity. SCIENCE ADVANCES 2024; 10:eadi7404. [PMID: 38416831 PMCID: PMC10901363 DOI: 10.1126/sciadv.adi7404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 01/24/2024] [Indexed: 03/01/2024]
Abstract
PTPN21 belongs to the four-point-one, ezrin, radixin, moesin (FERM) domain-containing protein tyrosine phosphatases (PTP) and plays important roles in cytoskeleton-associated cellular processes like cell adhesion, motility, and cargo transport. Because of the presence of a WPE loop instead of a WPD loop in the phosphatase domain, it is often considered to lack phosphatase activity. However, many of PTPN21's biological functions require its catalytic activity. To reconcile these findings, we have determined the structures of individual PTPN21 FERM, PTP domains, and a complex between FERM-PTP. Combined with biochemical analysis, we have found that PTPN21 PTP is weakly active and is autoinhibited by association with its FERM domain. Disruption of FERM-PTP interaction results in enhanced ERK activation. The oncogenic HPV18 E7 protein binds to PTP at the same location as PTPN21 FERM, indicating that it may act by displacing the FERM domain from PTP. Our results provide mechanistic insight into PTPN21 and benefit functional studies of PTPN21-mediated processes.
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Affiliation(s)
- Lu Chen
- Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Zijun Qian
- Department of Hematology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Yuyuan Zheng
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Jie Zhang
- Department of Hematology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Jie Sun
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Chun Zhou
- Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Haowen Xiao
- Department of Hematology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
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Du Y, Bradshaw WJ, Leisner TM, Annor-Gyamfi JK, Qian K, Bashore FM, Sikdar A, Nwogbo FO, Ivanov AA, Frye SV, Gileadi O, Brennan PE, Levey AI, Axtman AD, Pearce KH, Fu H, Katis VL. Discovery of FERM domain protein-protein interaction inhibitors for MSN and CD44 as a potential therapeutic approach for Alzheimer's disease. J Biol Chem 2023; 299:105382. [PMID: 37866628 PMCID: PMC10692723 DOI: 10.1016/j.jbc.2023.105382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 09/11/2023] [Accepted: 09/27/2023] [Indexed: 10/24/2023] Open
Abstract
Proteomic studies have identified moesin (MSN), a protein containing a four-point-one, ezrin, radixin, moesin (FERM) domain, and the receptor CD44 as hub proteins found within a coexpression module strongly linked to Alzheimer's disease (AD) traits and microglia. These proteins are more abundant in Alzheimer's patient brains, and their levels are positively correlated with cognitive decline, amyloid plaque deposition, and neurofibrillary tangle burden. The MSN FERM domain interacts with the phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2) and the cytoplasmic tail of CD44. Inhibiting the MSN-CD44 interaction may help limit AD-associated neuronal damage. Here, we investigated the feasibility of developing inhibitors that target this protein-protein interaction. We have employed structural, mutational, and phage-display studies to examine how CD44 binds to the FERM domain of MSN. Interestingly, we have identified an allosteric site located close to the PIP2 binding pocket that influences CD44 binding. These findings suggest a mechanism in which PIP2 binding to the FERM domain stimulates CD44 binding through an allosteric effect, leading to the formation of a neighboring pocket capable of accommodating a receptor tail. Furthermore, high-throughput screening of a chemical library identified two compounds that disrupt the MSN-CD44 interaction. One compound series was further optimized for biochemical activity, specificity, and solubility. Our results suggest that the FERM domain holds potential as a drug development target. Small molecule preliminary leads generated from this study could serve as a foundation for additional medicinal chemistry efforts with the goal of controlling microglial activity in AD by modifying the MSN-CD44 interaction.
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Affiliation(s)
- Yuhong Du
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA; Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - William J Bradshaw
- Alzheimer's Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, UK
| | - Tina M Leisner
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, North Carolina, USA
| | - Joel K Annor-Gyamfi
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Structural Genomics Consortium, Chapel Hill, North Carolina, USA
| | - Kun Qian
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA; Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Frances M Bashore
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Structural Genomics Consortium, Chapel Hill, North Carolina, USA
| | - Arunima Sikdar
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, North Carolina, USA
| | - Felix O Nwogbo
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, North Carolina, USA
| | - Andrey A Ivanov
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA; Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Stephen V Frye
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, North Carolina, USA
| | - Opher Gileadi
- Alzheimer's Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, UK
| | - Paul E Brennan
- Alzheimer's Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, UK
| | - Allan I Levey
- Department of Neurology, Emory Goizueta Alzheimer's Disease Research Center, Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Alison D Axtman
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Structural Genomics Consortium, Chapel Hill, North Carolina, USA.
| | - Kenneth H Pearce
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, North Carolina, USA.
| | - Haian Fu
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA; Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, Georgia, USA.
| | - Vittorio L Katis
- Alzheimer's Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, UK.
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5
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Du Y, Bradshaw WJ, Leisner TM, Annor-Gyamfi JK, Qian K, Bashore FM, Sikdar A, Nwogbo FO, Ivanov AA, Frye SV, Gileadi O, Brennan PE, Levey AI, Axtman AD, Pearce KH, Fu H, Katis VL. Development of FERM domain protein-protein interaction inhibitors for MSN and CD44 as a potential therapeutic strategy for Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.22.541727. [PMID: 37292860 PMCID: PMC10245921 DOI: 10.1101/2023.05.22.541727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Recent genome-wide association studies have revealed genetic risk factors for Alzheimer's disease (AD) that are exclusively expressed in microglia within the brain. A proteomics approach identified moesin (MSN), a FERM (four-point-one ezrin radixin moesin) domain protein, and the receptor CD44 as hub proteins found within a co-expression module strongly linked to AD clinical and pathological traits as well as microglia. The FERM domain of MSN interacts with the phospholipid PIP2 and the cytoplasmic tails of receptors such as CD44. This study explored the feasibility of developing protein-protein interaction inhibitors that target the MSN-CD44 interaction. Structural and mutational analyses revealed that the FERM domain of MSN binds to CD44 by incorporating a beta strand within the F3 lobe. Phage-display studies identified an allosteric site located close to the PIP2 binding site in the FERM domain that affects CD44 binding within the F3 lobe. These findings support a model in which PIP2 binding to the FERM domain stimulates receptor tail binding through an allosteric mechanism that causes the F3 lobe to adopt an open conformation permissive for binding. High-throughput screening of a chemical library identified two compounds that disrupt the MSN-CD44 interaction, and one compound series was further optimized for biochemical activity, specificity, and solubility. The results suggest that the FERM domain holds potential as a drug development target. The small molecule preliminary leads generated from the study could serve as a foundation for additional medicinal chemistry effort with the goal of controlling microglial activity in AD by modifying the MSN-CD44 interaction.
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Affiliation(s)
- Yuhong Du
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - William J. Bradshaw
- Alzheimer’s Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine Research Building, Old Road Campus, University of Oxford, Oxford, OX3 7FZ, UK
| | - Tina M. Leisner
- UNC Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, NC 27599, USA
| | - Joel K. Annor-Gyamfi
- UNC Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Structural Genomics Consortium, Chapel Hill, NC 27599, USA
| | - Kun Qian
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, GA 30322, USA
- Current address: Chemical Biology Consortium Sweden, Division of Chemical Biology and Genome Engineering, Department of Medical Biochemistry and Biophysics, Karolinska Institute, 171 65 Solna, Sweden
| | - Frances M. Bashore
- UNC Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Structural Genomics Consortium, Chapel Hill, NC 27599, USA
| | - Arunima Sikdar
- UNC Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, NC 27599, USA
| | - Felix O. Nwogbo
- UNC Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, NC 27599, USA
| | - Andrey A. Ivanov
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Stephen V. Frye
- UNC Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, NC 27599, USA
| | - Opher Gileadi
- Alzheimer’s Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine Research Building, Old Road Campus, University of Oxford, Oxford, OX3 7FZ, UK
- Current address: Structural Genomics Consortium, Department of Medicine, Karolinska Hospital and Karolinska Institute, 171 76 Stockholm, Sweden
| | - Paul E. Brennan
- Alzheimer’s Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine Research Building, Old Road Campus, University of Oxford, Oxford, OX3 7FZ, UK
| | - Allan I. Levey
- Department of Neurology, Emory Goizueta Alzheimer’s Disease Research Center, Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, GA 30322, USA
| | | | - Alison D. Axtman
- UNC Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Structural Genomics Consortium, Chapel Hill, NC 27599, USA
| | - Kenneth H. Pearce
- UNC Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Center for Integrative Chemical Biology and Drug Discovery, Chapel Hill, NC 27599, USA
| | - Haian Fu
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Vittorio L. Katis
- Alzheimer’s Research UK Oxford Drug Discovery Institute, Centre for Medicines Discovery, Nuffield Department of Medicine Research Building, Old Road Campus, University of Oxford, Oxford, OX3 7FZ, UK
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Mackrill JJ. Non-inositol 1,4,5-trisphosphate (IP3) receptor IP3-binding proteins. BIOCHIMICA ET BIOPHYSICA ACTA (BBA) - MOLECULAR CELL RESEARCH 2023; 1870:119470. [PMID: 37011730 DOI: 10.1016/j.bbamcr.2023.119470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/23/2023] [Accepted: 03/23/2023] [Indexed: 04/03/2023]
Abstract
Conventionally, myo-D-inositol 1, 4,5-trisphosphate (IP3) is thought to exert its second messenger effects through the gating of IP3R Ca2+ release channels, located in Ca2+-storage organelles like the endoplasmic reticulum. However, there is considerable indirect evidence to support the concept that IP3 might interact with other, non-IP3R proteins within cells. To explore this possibility further, the Protein Data Bank was searched using the term "IP3". This resulted in the retrieval of 203 protein structures, the majority of which were members of the IP3R/ryanodine receptor superfamily of channels. Only 49 of these structures were complexed with IP3. These were inspected for their ability to interact with the carbon-1 phosphate of IP3, since this is the least accessible phosphate group of its precursor, phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2). This reduced the number of structures retrieved to 35, of which 9 were IP3Rs. The remaining 26 structures represent a diverse range of proteins, including inositol-lipid metabolizing enzymes, signal transducers, PH domain containing proteins, cytoskeletal anchor proteins, the TRPV4 ion channel, a retroviral Gag protein and fibroblast growth factor 2. Such proteins may impact on IP3 signalling and its effects on cell-biology. This represents an area open for exploration in the field of IP3 signalling.
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Affiliation(s)
- John James Mackrill
- Department of Physiology, University College Cork, Western Gateway Building, Western Road, Cork T12 XF62, Ireland.
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7
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Xie T, Dong J, Zhou X, Tang D, Li D, Chen J, Chen Y, Xu H, Xue W, Liu D, Hong X, Tang F, Yin L, Dai Y. Proteomics analysis of lysine crotonylation and 2-hydroxyisobutyrylation reveals significant features of systemic lupus erythematosus. Clin Rheumatol 2022; 41:3851-3858. [PMID: 35941338 PMCID: PMC9652266 DOI: 10.1007/s10067-022-06254-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 05/14/2022] [Accepted: 06/15/2022] [Indexed: 11/28/2022]
Abstract
INTRODUCTION/OBJECTIVES To seek significant features of systemic lupus erythematosus (SLE) by utilizing bioinformatics analysis. METHOD Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to quantify lysine crotonylation (Kcr) and lysine 2-hydroxyisobutyrylation (Khib) in peripheral blood mononuclear cells (PBMCs) of systemic lupus erythematosus (SLE) patients and normal controls. RESULTS Seventy-six differentially modified proteins (DMPs) dually modified by Kcr and Khib were identified between SLE patients and healthy people. GO enrichment analysis prompted significant enrichment of seventy-six DMPs in MHC class II protein complex binding and leukocyte migration. KEGG pathways were enriched in antigen processing and presentation pathway and leukocyte transendothelial migration pathway. Six DMPs (CLTC, HSPA1B, HSPA8, HSP90AB1, HSPD1, and PDIA3) were identified in antigen processing and presentation pathway, of which HSPA8 was the core protein. Significant changes of Kcr and Khib in HSPA8 may increase ATP hydrolysis and promote antigen binding to MHC II molecule. In leukocyte transendothelial migration pathway, 7 DMPs (ACTN1, ACTN4, EZR, MSN, RAC1, RHOA, and VCL) were identified. MSN was the protein with the most modification sites in this pathway. In amino terminal ferm region of MSN, Kcr and Khib expression change may lead to the adhesion between leukocytes and endothelial cells, which was an important step of leukocyte migration. CONCLUSION Kcr and Khib may promote the antigen presentation and jointly regulate the tissue damage mediated by leukocyte migration in SLE patients, which may play key roles in the pathogenesis of SLE probably. Key Points • Antigen processing and presentation and leukocyte transendothelial migration may play key roles in the pathogenesis of SLE.
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Affiliation(s)
- Ting Xie
- Institute of Nephrology and Blood Purification, the First Affiliated Hospital of Jinan University, Guangzhou, 510632, Guangdong, China
| | - Jingjing Dong
- Institute of Nephrology and Blood Purification, the First Affiliated Hospital of Jinan University, Guangzhou, 510632, Guangdong, China
- Clinical Medical Research Center, the Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, Shenzhen, 518020, Guangdong, China
| | - Xianqing Zhou
- Department of Pathology, Guangxi Key Laboratory of Metabolic Diseases Research, No.924 Hospital of PLA Joint Logistic Support Force, Guilin, 541002, Guangxi, China
| | - Donge Tang
- Clinical Medical Research Center, the Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, Shenzhen, 518020, Guangdong, China
| | - Dandan Li
- Institute of Nephrology and Blood Purification, the First Affiliated Hospital of Jinan University, Guangzhou, 510632, Guangdong, China
| | - Jiejing Chen
- Department of Pathology, Guangxi Key Laboratory of Metabolic Diseases Research, No.924 Hospital of PLA Joint Logistic Support Force, Guilin, 541002, Guangxi, China
| | - Yumei Chen
- Clinical Medical Research Center, the Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, Shenzhen, 518020, Guangdong, China
| | - Huixuan Xu
- Clinical Medical Research Center, the Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, Shenzhen, 518020, Guangdong, China
| | - Wen Xue
- Department of Pathology, Guangxi Key Laboratory of Metabolic Diseases Research, No.924 Hospital of PLA Joint Logistic Support Force, Guilin, 541002, Guangxi, China
| | - Dongzhou Liu
- Clinical Medical Research Center, the Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, Shenzhen, 518020, Guangdong, China
| | - Xiaoping Hong
- Clinical Medical Research Center, the Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, Shenzhen, 518020, Guangdong, China
| | - Fang Tang
- Department of Pathology, Guangxi Key Laboratory of Metabolic Diseases Research, No.924 Hospital of PLA Joint Logistic Support Force, Guilin, 541002, Guangxi, China.
| | - Lianghong Yin
- Institute of Nephrology and Blood Purification, the First Affiliated Hospital of Jinan University, Guangzhou, 510632, Guangdong, China.
| | - Yong Dai
- Clinical Medical Research Center, the Second Clinical Medical College of Jinan University, Shenzhen People's Hospital, Shenzhen, 518020, Guangdong, China.
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Kawaguchi K, Asano S. Pathophysiological Roles of Actin-Binding Scaffold Protein, Ezrin. Int J Mol Sci 2022; 23:ijms23063246. [PMID: 35328667 PMCID: PMC8952289 DOI: 10.3390/ijms23063246] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/14/2022] [Accepted: 03/14/2022] [Indexed: 02/06/2023] Open
Abstract
Ezrin is one of the members of the ezrin/radixin/moesin (ERM) family of proteins. It was originally discovered as an actin-binding protein in the microvilli structure about forty years ago. Since then, it has been revealed as a key protein with functions in a variety of fields including cell migration, survival, and signal transduction, as well as functioning as a structural component. Ezrin acts as a cross-linker of membrane proteins or phospholipids in the plasma membrane and the actin cytoskeleton. It also functions as a platform for signaling molecules at the cell surface. Moreover, ezrin is regarded as an important target protein in cancer diagnosis and therapy because it is a key protein involved in cancer progression and metastasis, and its high expression is linked to poor survival in many cancers. Small molecule inhibitors of ezrin have been developed and investigated as candidate molecules that suppress cancer metastasis. Here, we wish to comprehensively review the roles of ezrin from the pathophysiological points of view.
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9
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Chen D, Yu W, Aitken L, Gunn-Moore F. Willin/FRMD6: A Multi-Functional Neuronal Protein Associated with Alzheimer's Disease. Cells 2021; 10:cells10113024. [PMID: 34831245 PMCID: PMC8616527 DOI: 10.3390/cells10113024] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/24/2021] [Accepted: 10/25/2021] [Indexed: 12/18/2022] Open
Abstract
The FERM domain-containing protein 6 (FRMD6), also known as Willin, is an upstream regulator of Hippo signaling that has recently been shown to modulate actin cytoskeleton dynamics and mechanical phenotype of neuronal cells through ERK signaling. Physiological functions of Willin/FRMD6 in the nervous system include neuronal differentiation, myelination, nerve injury repair, and vesicle exocytosis. The newly established neuronal role of Willin/FRMD6 is of particular interest given the mounting evidence suggesting a role for Willin/FRMD6 in Alzheimer's disease (AD), including a series of genome wide association studies that position Willin/FRMD6 as a novel AD risk gene. Here we describe recent findings regarding the role of Willin/FRMD6 in the nervous system and its actions in cellular perturbations related to the pathogenesis of AD.
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10
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Salman A, Hutton SB, Newall T, Scott JA, Griffiths HL, Lee H, Gomez-Nicola D, Lotery AJ, Self JE. Characterization of the Frmd7 Knock-Out Mice Generated by the EUCOMM/COMP Repository as a Model for Idiopathic Infantile Nystagmus (IIN). Genes (Basel) 2020; 11:genes11101157. [PMID: 33007925 PMCID: PMC7601595 DOI: 10.3390/genes11101157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/21/2020] [Accepted: 09/24/2020] [Indexed: 12/30/2022] Open
Abstract
In this study, we seek to exclude other pathophysiological mechanisms by which Frmd7 knock-down may cause Idiopathic Infantile Nystagmus (IIN) using the Frmd7.tm1a and Frmd7.tm1b murine models. We used a combination of genetic, histological and visual function techniques to characterize the role of Frmd7 gene in IIN using a novel murine model for the disease. We demonstrate that the Frmd7.tm1b allele represents a more robust model of Frmd7 knock-out at the mRNA level. The expression of Frmd7 was investigated using both antibody staining and X-gal staining confirming previous reports that Frmd7 expression in the retina is restricted to starburst amacrine cells and demonstrating that X-gal staining recapitulates the expression pattern in this model. Thus, it offers a useful tool for further expression studies. We also show that gross retinal morphology and electrophysiology are unchanged in these Frmd7 mutant models when compared with wild-type mice. High-speed eye-tracking recordings of Frmd7 mutant mice confirm a specific horizontal optokinetic reflex defect. In summary, our study confirms the likely role for Frmd7 in the optokinetic reflex in mice mediated by starburst amacrine cells. We show that the Frmd7.tm1b model provides a more robust knock-out than the Frmd7.tm1a model at the mRNA level, although the functional consequence is unchanged. Finally, we establish a robust eye-tracking technique in mice that can be used in a variety of future studies using this model and others. Although our data highlight a deficit in the optiokinetic reflex as a result of the starburst amacrine cells in the retina, this does not rule out the involvement of other cells, in the brain or the retina where Frmd7 is expressed, in the pathophysiology of IIN.
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MESH Headings
- Alleles
- Amacrine Cells/metabolism
- Animals
- Cytoskeletal Proteins/genetics
- Cytoskeletal Proteins/metabolism
- Disease Models, Animal
- Electroretinography
- Female
- Gene Expression
- Genetic Diseases, X-Linked/genetics
- Genetic Diseases, X-Linked/pathology
- Genetic Diseases, X-Linked/physiopathology
- Male
- Mice
- Mice, Knockout
- Mutation
- Nystagmus, Congenital/genetics
- Nystagmus, Congenital/pathology
- Nystagmus, Congenital/physiopathology
- Nystagmus, Optokinetic
- Retina/metabolism
- Retina/pathology
- Retina/physiopathology
- Tomography, Optical Coherence
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Affiliation(s)
- Ahmed Salman
- Clinical and Experimental Neurosciences, University of Southampton, Southampton SO16 6YD, UK; (T.N.); (J.A.S.); (H.L.G.); (H.L.); (A.J.L.); (J.E.S.)
- Correspondence:
| | - Samuel B. Hutton
- School of Psychology, University of Sussex, Brighton BN1 9QH, UK;
| | - Tutte Newall
- Clinical and Experimental Neurosciences, University of Southampton, Southampton SO16 6YD, UK; (T.N.); (J.A.S.); (H.L.G.); (H.L.); (A.J.L.); (J.E.S.)
| | - Jennifer A. Scott
- Clinical and Experimental Neurosciences, University of Southampton, Southampton SO16 6YD, UK; (T.N.); (J.A.S.); (H.L.G.); (H.L.); (A.J.L.); (J.E.S.)
| | - Helen L. Griffiths
- Clinical and Experimental Neurosciences, University of Southampton, Southampton SO16 6YD, UK; (T.N.); (J.A.S.); (H.L.G.); (H.L.); (A.J.L.); (J.E.S.)
| | - Helena Lee
- Clinical and Experimental Neurosciences, University of Southampton, Southampton SO16 6YD, UK; (T.N.); (J.A.S.); (H.L.G.); (H.L.); (A.J.L.); (J.E.S.)
| | - Diego Gomez-Nicola
- School of Biological Sciences, University of Southampton, Southampton SO171BJ, UK;
| | - Andrew J. Lotery
- Clinical and Experimental Neurosciences, University of Southampton, Southampton SO16 6YD, UK; (T.N.); (J.A.S.); (H.L.G.); (H.L.); (A.J.L.); (J.E.S.)
| | - Jay E. Self
- Clinical and Experimental Neurosciences, University of Southampton, Southampton SO16 6YD, UK; (T.N.); (J.A.S.); (H.L.G.); (H.L.); (A.J.L.); (J.E.S.)
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11
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Martinelli L, Adamopoulos A, Johansson P, Wan PT, Gunnarsson J, Guo H, Boyd H, Zelcer N, Sixma TK. Structural analysis of the LDL receptor-interacting FERM domain in the E3 ubiquitin ligase IDOL reveals an obscured substrate-binding site. J Biol Chem 2020; 295:13570-13583. [PMID: 32727844 PMCID: PMC7521653 DOI: 10.1074/jbc.ra120.014349] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/21/2020] [Indexed: 12/31/2022] Open
Abstract
Hepatic abundance of the low-density lipoprotein receptor (LDLR) is a critical determinant of circulating plasma LDL cholesterol levels and hence development of coronary artery disease. The sterol-responsive E3 ubiquitin ligase inducible degrader of the LDLR (IDOL) specifically promotes ubiquitination and subsequent lysosomal degradation of the LDLR and thus controls cellular LDL uptake. IDOL contains an extended N-terminal FERM (4.1 protein, ezrin, radixin, and moesin) domain, responsible for substrate recognition and plasma membrane association, and a second C-terminal RING domain, responsible for the E3 ligase activity and homodimerization. As IDOL is a putative lipid-lowering drug target, we investigated the molecular details of its substrate recognition. We produced and isolated full-length IDOL protein, which displayed high autoubiquitination activity. However, in vitro ubiquitination of its substrate, the intracellular tail of the LDLR, was low. To investigate the structural basis for this, we determined crystal structures of the extended FERM domain of IDOL and multiple conformations of its F3ab subdomain. These reveal the archetypal F1-F2-F3 trilobed FERM domain structure but show that the F3c subdomain orientation obscures the target-binding site. To substantiate this finding, we analyzed the full-length FERM domain and a series of truncated FERM constructs by small-angle X-ray scattering (SAXS). The scattering data support a compact and globular core FERM domain with a more flexible and extended C-terminal region. This flexibility may explain the low activity in vitro and suggests that IDOL may require activation for recognition of the LDLR.
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Affiliation(s)
- Luca Martinelli
- Division of Biochemistry, Netherlands Cancer Institute, Amsterdam, The Netherlands; Department of Medical Biochemistry, Amsterdam UMC, Amsterdam Cardiovascular Sciences and Gastroenterology and Metabolism, University of Amsterdam, Amsterdam, the Netherlands
| | | | - Patrik Johansson
- IMED Biotech Unit, Discovery Sciences, AstraZeneca, Mölndal, Sweden
| | - Paul T Wan
- IMED Biotech Unit, Discovery Sciences, AstraZeneca, Mölndal, Sweden
| | - Jenny Gunnarsson
- IMED Biotech Unit, Discovery Sciences, AstraZeneca, Mölndal, Sweden
| | - Hongwei Guo
- IMED Biotech Unit, Discovery Sciences, AstraZeneca, Mölndal, Sweden
| | - Helen Boyd
- IMED Biotech Unit, Discovery Sciences, AstraZeneca, Mölndal, Sweden
| | - Noam Zelcer
- Department of Medical Biochemistry, Amsterdam UMC, Amsterdam Cardiovascular Sciences and Gastroenterology and Metabolism, University of Amsterdam, Amsterdam, the Netherlands.
| | - Titia K Sixma
- Division of Biochemistry, Netherlands Cancer Institute, Amsterdam, The Netherlands; Oncode Institute, Utrecht, The Netherlands.
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12
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Michie KA, Bermeister A, Robertson NO, Goodchild SC, Curmi PMG. Two Sides of the Coin: Ezrin/Radixin/Moesin and Merlin Control Membrane Structure and Contact Inhibition. Int J Mol Sci 2019; 20:ijms20081996. [PMID: 31018575 PMCID: PMC6515277 DOI: 10.3390/ijms20081996] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/16/2019] [Accepted: 04/19/2019] [Indexed: 12/21/2022] Open
Abstract
The merlin-ERM (ezrin, radixin, moesin) family of proteins plays a central role in linking the cellular membranes to the cortical actin cytoskeleton. Merlin regulates contact inhibition and is an integral part of cell–cell junctions, while ERM proteins, ezrin, radixin and moesin, assist in the formation and maintenance of specialized plasma membrane structures and membrane vesicle structures. These two protein families share a common evolutionary history, having arisen and separated via gene duplication near the origin of metazoa. During approximately 0.5 billion years of evolution, the merlin and ERM family proteins have maintained both sequence and structural conservation to an extraordinary level. Comparing crystal structures of merlin-ERM proteins and their complexes, a picture emerges of the merlin-ERM proteins acting as switchable interaction hubs, assembling protein complexes on cellular membranes and linking them to the actin cytoskeleton. Given the high level of structural conservation between the merlin and ERM family proteins we speculate that they may function together.
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Affiliation(s)
- Katharine A Michie
- School of Physics, University of New South Wales, Sydney 2052, Australia.
| | - Adam Bermeister
- School of Physics, University of New South Wales, Sydney 2052, Australia.
| | - Neil O Robertson
- School of Physics, University of New South Wales, Sydney 2052, Australia.
| | - Sophia C Goodchild
- Department of Molecular Sciences, Macquarie University, Sydney 2109, Australia.
| | - Paul M G Curmi
- School of Physics, University of New South Wales, Sydney 2052, Australia.
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13
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Zhang L, Shen H, Gong Y, Pang X, Yi M, Guo L, Li J, Arroyo S, Lu X, Ovchinnikov S, Cheng G, Liu X, Jiang X, Feng S, Deng H. Development of a dual-functional conjugate of antigenic peptide and Fc-III mimetics (DCAF) for targeted antibody blocking. Chem Sci 2019; 10:3271-3280. [PMID: 30996912 PMCID: PMC6429600 DOI: 10.1039/c8sc05273e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 01/28/2019] [Indexed: 01/12/2023] Open
Abstract
Targeted antibody blocking enables characterization of binding sites on immunoglobulin G (IgG), and can efficiently eliminate harmful antibodies from organisms. In this report, we present a novel peptide-denoted as a dual-functional conjugate of antigenic peptide and Fc-III mimetics (DCAF)-for targeted blocking of antibodies. Synthesis of DCAF was achieved by native chemical ligation, and the molecule consists of three functional parts: a specific antigenic peptide, a linker and the Fc-III mimetic peptide, which has a high affinity toward the Fc region of IgG molecules. We demonstrate that DCAF binds the cognate antibody with high selectivity by simultaneously binding to the Fab and Fc regions of IgG. Animal experiments revealed that DCAF molecules diminish the antibody-dependent enhancement effect in a dengue virus infection model, and rescue the acetylcholine receptor by inhibiting the complement cascade in a myasthenia gravis model. These results suggest that DCAFs could have utility in the development of new therapeutics against harmful antibodies.
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Affiliation(s)
- Lin Zhang
- MOE Key Laboratory of Bioinformatics , Center for Synthetic and Systems Biology , School of Life Sciences , Tsinghua University , Beijing , China .
| | - Hao Shen
- Institute for Protein Design , Department of Biochemistry , University of Washington , Seattle , WA , USA
| | - Yiyi Gong
- Central Research Laboratory , Peking Union Medical College Hospital , Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing , China
| | - Xiaojing Pang
- Tsinghua-Peking Center for Life Sciences , School of Medicine , Tsinghua University , Beijing , China
| | - Meiqi Yi
- MOE Key Laboratory of Bioinformatics , Center for Synthetic and Systems Biology , School of Life Sciences , Tsinghua University , Beijing , China .
| | - Lin Guo
- MOE Key Laboratory of Bioinformatics , Center for Synthetic and Systems Biology , School of Life Sciences , Tsinghua University , Beijing , China .
| | - Jin Li
- MOE Key Laboratory of Bioinformatics , Center for Synthetic and Systems Biology , School of Life Sciences , Tsinghua University , Beijing , China .
| | - Sam Arroyo
- Department of Biological Sciences , University of Notre Dame , South Bend , IN , USA
| | - Xin Lu
- Department of Biological Sciences , University of Notre Dame , South Bend , IN , USA
| | - Sergey Ovchinnikov
- Institute for Protein Design , Department of Biochemistry , University of Washington , Seattle , WA , USA
| | - Gong Cheng
- Tsinghua-Peking Center for Life Sciences , School of Medicine , Tsinghua University , Beijing , China
| | - Xudong Liu
- Central Research Laboratory , Peking Union Medical College Hospital , Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing , China
| | - Xu Jiang
- Central Research Laboratory , Peking Union Medical College Hospital , Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing , China
| | - Shan Feng
- Mass Spectrometry Facility , Westlake Lake University , Hangzhou , Zhejiang Province , China .
| | - Haiteng Deng
- MOE Key Laboratory of Bioinformatics , Center for Synthetic and Systems Biology , School of Life Sciences , Tsinghua University , Beijing , China .
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14
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Pemberton JG, Balla T. Polyphosphoinositide-Binding Domains: Insights from Peripheral Membrane and Lipid-Transfer Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1111:77-137. [PMID: 30483964 DOI: 10.1007/5584_2018_288] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Within eukaryotic cells, biochemical reactions need to be organized on the surface of membrane compartments that use distinct lipid constituents to dynamically modulate the functions of integral proteins or influence the selective recruitment of peripheral membrane effectors. As a result of these complex interactions, a variety of human pathologies can be traced back to improper communication between proteins and membrane surfaces; either due to mutations that directly alter protein structure or as a result of changes in membrane lipid composition. Among the known structural lipids found in cellular membranes, phosphatidylinositol (PtdIns) is unique in that it also serves as the membrane-anchored precursor of low-abundance regulatory lipids, the polyphosphoinositides (PPIn), which have restricted distributions within specific subcellular compartments. The ability of PPIn lipids to function as signaling platforms relies on both non-specific electrostatic interactions and the selective stereospecific recognition of PPIn headgroups by specialized protein folds. In this chapter, we will attempt to summarize the structural diversity of modular PPIn-interacting domains that facilitate the reversible recruitment and conformational regulation of peripheral membrane proteins. Outside of protein folds capable of capturing PPIn headgroups at the membrane interface, recent studies detailing the selective binding and bilayer extraction of PPIn species by unique functional domains within specific families of lipid-transfer proteins will also be highlighted. Overall, this overview will help to outline the fundamental physiochemical mechanisms that facilitate localized interactions between PPIn lipids and the wide-variety of PPIn-binding proteins that are essential for the coordinate regulation of cellular metabolism and membrane dynamics.
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Affiliation(s)
- Joshua G Pemberton
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Tamas Balla
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
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15
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Mu L, Tu Z, Miao L, Ruan H, Kang N, Hei Y, Chen J, Wei W, Gong F, Wang B, Du Y, Ma G, Amerein MW, Xia T, Shi Y. A phosphatidylinositol 4,5-bisphosphate redistribution-based sensing mechanism initiates a phagocytosis programing. Nat Commun 2018; 9:4259. [PMID: 30323235 PMCID: PMC6189171 DOI: 10.1038/s41467-018-06744-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 09/20/2018] [Indexed: 12/30/2022] Open
Abstract
Phagocytosis is one of the earliest cellular functions, developing approximately 2 billion years ago. Although FcR-based phagocytic signaling is well-studied, how it originated from ancient phagocytosis is unknown. Lipid redistribution upregulates a phagocytic program recapitulating FcR-based phagocytosis with complete dependence on Src family kinases, Syk, and phosphoinositide 3-kinases (PI3K). Here we show that in phagocytes, an atypical ITAM sequence in the ancient membrane anchor protein Moesin transduces signal without receptor activation. Plasma membrane deformation created by solid structure binding generates phosphatidylinositol 4,5-bisphosphate (PIP2) accumulation at the contact site, which binds the Moesin FERM domain and relocalizes Syk to the membrane via the ITAM motif. Phylogenic analysis traces this signaling using PI3K and Syk to 0.8 billion years ago, earlier than immune receptor signaling. The proposed general model of solid structure phagocytosis implies a preexisting lipid redistribution-based activation platform collecting intracellular signaling components for the emergence of immune receptors.
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Affiliation(s)
- Libing Mu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine; Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Zhongyuan Tu
- Department of Microbiology, Immunology & Infectious Diseases and Snyder Institute, University of Calgary, Calgary, T2N 4N1, AB, Canada
| | - Lin Miao
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine; Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
- School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Hefei Ruan
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine; Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Ning Kang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine; Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yongzhen Hei
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine; Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jiahuan Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine; Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Wei Wei
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Fangling Gong
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Bingjie Wang
- Department of Biomedical Engineering, School of Medicine, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Tsinghua University, Beijing, 100084, China
| | - Yanan Du
- Department of Biomedical Engineering, School of Medicine, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Tsinghua University, Beijing, 100084, China
| | - Guanghui Ma
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China
| | - Matthias W Amerein
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, T2N 4N1, AB, Canada
- Snyder Institute of Chronic Diseases, University of Calgary, Calgary, T2N 4N1, AB, Canada
| | - Tie Xia
- School of Life Sciences, Tsinghua University, Beijing, 100084, China.
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine; Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China.
| | - Yan Shi
- School of Life Sciences, Tsinghua University, Beijing, 100084, China.
- Institute for Immunology and Department of Basic Medical Sciences, Beijing Key Lab for Immunological Research on Chronic Diseases, School of Medicine; Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China.
- Department of Microbiology, Immunology & Infectious Diseases and Snyder Institute, University of Calgary, Calgary, T2N 4N1, AB, Canada.
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16
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Duran CL, Howell DW, Dave JM, Smith RL, Torrie ME, Essner JJ, Bayless KJ. Molecular Regulation of Sprouting Angiogenesis. Compr Physiol 2017; 8:153-235. [PMID: 29357127 DOI: 10.1002/cphy.c160048] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The term angiogenesis arose in the 18th century. Several studies over the next 100 years laid the groundwork for initial studies performed by the Folkman laboratory, which were at first met with some opposition. Once overcome, the angiogenesis field has flourished due to studies on tumor angiogenesis and various developmental models that can be genetically manipulated, including mice and zebrafish. In addition, new discoveries have been aided by the ability to isolate primary endothelial cells, which has allowed dissection of various steps within angiogenesis. This review will summarize the molecular events that control angiogenesis downstream of biochemical factors such as growth factors, cytokines, chemokines, hypoxia-inducible factors (HIFs), and lipids. These and other stimuli have been linked to regulation of junctional molecules and cell surface receptors. In addition, the contribution of cytoskeletal elements and regulatory proteins has revealed an intricate role for mobilization of actin, microtubules, and intermediate filaments in response to cues that activate the endothelium. Activating stimuli also affect various focal adhesion proteins, scaffold proteins, intracellular kinases, and second messengers. Finally, metalloproteinases, which facilitate matrix degradation and the formation of new blood vessels, are discussed, along with our knowledge of crosstalk between the various subclasses of these molecules throughout the text. Compr Physiol 8:153-235, 2018.
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Affiliation(s)
- Camille L Duran
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, Texas, USA
| | - David W Howell
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, Texas, USA
| | - Jui M Dave
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, Texas, USA
| | - Rebecca L Smith
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, Texas, USA
| | - Melanie E Torrie
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa, USA
| | - Jeffrey J Essner
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa, USA
| | - Kayla J Bayless
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, Texas, USA
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17
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Mechanistic principles underlying regulation of the actin cytoskeleton by phosphoinositides. Proc Natl Acad Sci U S A 2017; 114:E8977-E8986. [PMID: 29073094 DOI: 10.1073/pnas.1705032114] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The actin cytoskeleton powers membrane deformation during many cellular processes, such as migration, morphogenesis, and endocytosis. Membrane phosphoinositides, especially phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], regulate the activities of many actin-binding proteins (ABPs), including profilin, cofilin, Dia2, N-WASP, ezrin, and moesin, but the underlying molecular mechanisms have remained elusive. Moreover, because of a lack of available methodology, the dynamics of membrane interactions have not been experimentally determined for any ABP. Here, we applied a combination of biochemical assays, photobleaching/activation approaches, and atomistic molecular dynamics simulations to uncover the molecular principles by which ABPs interact with phosphoinositide-rich membranes. We show that, despite using different domains for lipid binding, these proteins associate with membranes through similar multivalent electrostatic interactions, without specific binding pockets or penetration into the lipid bilayer. Strikingly, our experiments reveal that these proteins display enormous differences in the dynamics of membrane interactions and in the ranges of phosphoinositide densities that they sense. Profilin and cofilin display transient, low-affinity interactions with phosphoinositide-rich membranes, whereas F-actin assembly factors Dia2 and N-WASP reside on phosphoinositide-rich membranes for longer periods to perform their functions. Ezrin and moesin, which link the actin cytoskeleton to the plasma membrane, bind membranes with very high affinity and slow dissociation dynamics. Unlike profilin, cofilin, Dia2, and N-WASP, they do not require high "stimulus-responsive" phosphoinositide density for membrane binding. Moreover, ezrin can limit the lateral diffusion of PI(4,5)P2 along the lipid bilayer. Together, these findings demonstrate that membrane-interaction mechanisms of ABPs evolved to precisely fulfill their specific functions in cytoskeletal dynamics.
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18
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Clausen MP, Colin-York H, Schneider F, Eggeling C, Fritzsche M. Dissecting the actin cortex density and membrane-cortex distance in living cells by super-resolution microscopy. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2017; 50:064002. [PMID: 28458398 PMCID: PMC5390943 DOI: 10.1088/1361-6463/aa52a1] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 11/30/2016] [Accepted: 12/08/2016] [Indexed: 05/30/2023]
Abstract
Nanoscale spacing between the plasma membrane and the underlying cortical actin cytoskeleton profoundly modulates cellular morphology, mechanics, and function. Measuring this distance has been a key challenge in cell biology. Current methods for dissecting the nanoscale spacing either limit themselves to complex survey design using fixed samples or rely on diffraction-limited fluorescence imaging whose spatial resolution is insufficient to quantify distances on the nanoscale. Using dual-color super-resolution STED (stimulated-emission-depletion) microscopy, we here overcome this challenge and accurately measure the density distribution of the cortical actin cytoskeleton and the distance between the actin cortex and the membrane in live Jurkat T-cells. We found an asymmetric cortical actin density distribution with a mean width of 230 (+105/-125) nm. The spatial distances measured between the maximum density peaks of the cortex and the membrane were bi-modally distributed with mean values of 50 ± 15 nm and 120 ± 40 nm, respectively. Taken together with the finite width of the cortex, our results suggest that in some regions the cortical actin is closer than 10 nm to the membrane and a maximum of 20 nm in others.
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Affiliation(s)
- M P Clausen
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, UK
- Department of Physics, Chemistry, and Pharmacy, MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - H Colin-York
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, UK
| | - F Schneider
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, UK
| | - C Eggeling
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, UK
| | - M Fritzsche
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, UK
- Kennedy Institute for Rheumatology, Roosevelt Drive, University of Oxford, Oxford OX3 7LF Oxford, UK
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19
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Structural characterization suggests models for monomeric and dimeric forms of full-length ezrin. Biochem J 2016; 473:2763-82. [DOI: 10.1042/bcj20160541] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 06/29/2016] [Indexed: 12/12/2022]
Abstract
Ezrin is a member of the ERM (ezrin–radixin–moesin) family of proteins that have been conserved through metazoan evolution. These proteins have dormant and active forms, where the latter links the actin cytoskeleton to membranes. ERM proteins have three domains: an N-terminal FERM [band Four-point-one (4.1) ERM] domain comprising three subdomains (F1, F2, and F3); a helical domain; and a C-terminal actin-binding domain. In the dormant form, FERM and C-terminal domains form a stable complex. We have determined crystal structures of the active FERM domain and the dormant FERM:C-terminal domain complex of human ezrin. We observe a bistable array of phenylalanine residues in the core of subdomain F3 that is mobile in the active form and locked in the dormant form. As subdomain F3 is pivotal in binding membrane proteins and phospholipids, these transitions may facilitate activation and signaling. Full-length ezrin forms stable monomers and dimers. We used small-angle X-ray scattering to determine the solution structures of these species. As expected, the monomer shows a globular domain with a protruding helical coiled coil. The dimer shows an elongated dumbbell structure that is twice as long as the monomer. By aligning ERM sequences spanning metazoan evolution, we show that the central helical region is conserved, preserving the heptad repeat. Using this, we have built a dimer model where each monomer forms half of an elongated antiparallel coiled coil with domain-swapped FERM:C-terminal domain complexes at each end. The model suggests that ERM dimers may bind to actin in a parallel fashion.
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Gianazza E, Parravicini C, Primi R, Miller I, Eberini I. In silico prediction and characterization of protein post-translational modifications. J Proteomics 2015; 134:65-75. [PMID: 26436211 DOI: 10.1016/j.jprot.2015.09.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Revised: 07/17/2015] [Accepted: 09/23/2015] [Indexed: 01/06/2023]
Abstract
This review outlines the computational approaches and procedures for predicting post translational modification (PTM)-induced changes in protein conformation and their influence on protein function(s), the latter being assessed as differential affinity in interaction with either low (ligands for receptors or transporters, substrates for enzymes) or high molecular mass molecules (proteins or nucleic acids in supramolecular assemblies). The scope for an in silico approach is discussed against a summary of the in vitro evidence on the structural and functional outcome of protein PTM.
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Affiliation(s)
- Elisabetta Gianazza
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Gruppo di Studio per la Proteomica e la Struttura delle Proteine, Sezione di Scienze Farmacologiche, Via Balzaretti 9, I-20133 Milan, Italy.
| | - Chiara Parravicini
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Laboratorio di Biochimica e Biofisica Computazionale, Sezione di Biochimica, Biofisica, Fisiologia ed Immunopatologia, Via Trentacoste, 2, I-20134 Milan, Italy
| | - Roberto Primi
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Laboratorio di Biochimica e Biofisica Computazionale, Sezione di Biochimica, Biofisica, Fisiologia ed Immunopatologia, Via Trentacoste, 2, I-20134 Milan, Italy
| | - Ingrid Miller
- Institut für Medizinische Biochemie, Veterinärmedizinische Universität Wien, Veterinärplatz 1, A-1210 Vienna, Austria
| | - Ivano Eberini
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Laboratorio di Biochimica e Biofisica Computazionale, Sezione di Biochimica, Biofisica, Fisiologia ed Immunopatologia, Via Trentacoste, 2, I-20134 Milan, Italy
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21
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Target-selective protein S-nitrosylation by sequence motif recognition. Cell 2014; 159:623-34. [PMID: 25417112 DOI: 10.1016/j.cell.2014.09.032] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 08/07/2014] [Accepted: 09/10/2014] [Indexed: 11/20/2022]
Abstract
S-nitrosylation is a ubiquitous protein modification emerging as a principal mechanism of nitric oxide (NO)-mediated signal transduction and cell function. S-nitrosylases can use NO synthase (NOS)-derived NO to modify selected cysteines in target proteins. Despite proteomic identification of over a thousand S-nitrosylated proteins, few S-nitrosylases have been identified. Moreover, mechanisms underlying site-selective S-nitrosylation and the potential role of specific sequence motifs remain largely unknown. Here, we describe a stimulus-inducible, heterotrimeric S-nitrosylase complex consisting of inducible NOS (iNOS), S100A8, and S100A9. S100A9 exhibits transnitrosylase activity, shuttling NO from iNOS to the target protein, whereas S100A8 and S100A9 coordinately direct site selection. A family of proteins S-nitrosylated by iNOS-S100A8/A9 were revealed by proteomic analysis. A conserved I/L-X-C-X2-D/E motif was necessary and sufficient for iNOS-S100A8/A9-mediated S-nitrosylation. These results reveal an elusive parallel between protein S-nitrosylation and phosphorylation, namely, stimulus-dependent posttranslational modification of selected targets by primary sequence motif recognition.
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Stahelin RV, Scott JL, Frick CT. Cellular and molecular interactions of phosphoinositides and peripheral proteins. Chem Phys Lipids 2014; 182:3-18. [PMID: 24556335 DOI: 10.1016/j.chemphyslip.2014.02.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 02/05/2014] [Accepted: 02/05/2014] [Indexed: 12/23/2022]
Abstract
Anionic lipids act as signals for the recruitment of proteins containing cationic clusters to biological membranes. A family of anionic lipids known as the phosphoinositides (PIPs) are low in abundance, yet play a critical role in recruitment of peripheral proteins to the membrane interface. PIPs are mono-, bis-, or trisphosphorylated derivatives of phosphatidylinositol (PI) yielding seven species with different structure and anionic charge. The differential spatial distribution and temporal appearance of PIPs is key to their role in communicating information to target proteins. Selective recognition of PIPs came into play with the discovery that the substrate of protein kinase C termed pleckstrin possessed the first PIP binding region termed the pleckstrin homology (PH) domain. Since the discovery of the PH domain, more than ten PIP binding domains have been identified including PH, ENTH, FYVE, PX, and C2 domains. Representative examples of each of these domains have been thoroughly characterized to understand how they coordinate PIP headgroups in membranes, translocate to specific membrane docking sites in the cell, and function to regulate the activity of their full-length proteins. In addition, a number of novel mechanisms of PIP-mediated membrane association have emerged, such as coincidence detection-specificity for two distinct lipid headgroups. Other PIP-binding domains may also harbor selectivity for a membrane physical property such as charge or membrane curvature. This review summarizes the current understanding of the cellular distribution of PIPs and their molecular interaction with peripheral proteins.
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Affiliation(s)
- Robert V Stahelin
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine-South Bend, South Bend, IN 46617, United States; Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, United States; Mike and Josie Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556, United States.
| | - Jordan L Scott
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, United States; Mike and Josie Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556, United States
| | - Cary T Frick
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, United States
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23
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Parameswaran N, Gupta N. Re-defining ERM function in lymphocyte activation and migration. Immunol Rev 2013; 256:63-79. [DOI: 10.1111/imr.12104] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Neetha Parameswaran
- Department of Immunology; Lerner Research Institute; Cleveland Clinic; Cleveland OH USA
| | - Neetu Gupta
- Department of Immunology; Lerner Research Institute; Cleveland Clinic; Cleveland OH USA
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24
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Abstract
Our understanding of the FERM (4.1/ezrin/radixin/moesin) protein family has been rapidly expanding in the last few years, with the result that many new physiological functions have been ascribed to these biochemically unique proteins. In the present review, we will discuss a number of new FRMD (FERM domain)-containing proteins that were initially discovered from genome sequencing but are now being established through biochemical and genetic studies to be involved both in normal cellular processes, but are also associated with a variety of human diseases.
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25
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Deng W, Cho S, Li R. FERM domain of moesin desorbs the basic-rich cytoplasmic domain of l-selectin from the anionic membrane surface. J Mol Biol 2013; 425:3549-62. [PMID: 23796515 DOI: 10.1016/j.jmb.2013.06.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 06/13/2013] [Accepted: 06/14/2013] [Indexed: 01/08/2023]
Abstract
Moesin and calmodulin (CaM) jointly associate with the cytoplasmic domain of l-selectin in the cell to modulate the function and ectodomain shedding of l-selectin. Using fluorescence spectroscopy, we have examined the association of moesin FERM domain with the recombinant transmembrane and cytoplasmic domains of l-selectin (CLS) reconstituted in model phospholipid liposomes. The dissociation constant of moesin FERM domain to CLS in the phosphatidylcholine liposome is about 300nM. In contrast to disrupting the CaM association with CLS, inclusion of anionic phosphatidylserine lipids in the phosphatidylcholine liposome increased the apparent binding affinity of moesin FERM domain for CLS. Using the environmentally sensitive fluorescent probe attached to the cytoplasmic domain of CLS and the nitroxide quencher attached to the lipid bilayer, we showed that the association of moesin FERM domain induced the desorption of the basic-rich cytoplasmic domain of CLS from the anionic membrane surface, which enabled subsequent association of CaM to the cytoplasmic domain of CLS. These results have elucidated the molecular basis for the moesin/l-selectin/CaM ternary complex and suggested an important role of phospholipids in modulating l-selectin function and shedding.
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Affiliation(s)
- Wei Deng
- Aflac Cancer and Blood Disorders Center, Department of Pediatrics, Emory University School of Medicine, 2015 Uppergate Drive NE, Room 440, Atlanta, GA 30322, USA
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26
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Jiang L, Phang JM, Yu J, Harrop SJ, Sokolova AV, Duff AP, Wilk KE, Alkhamici H, Breit SN, Valenzuela SM, Brown LJ, Curmi PMG. CLIC proteins, ezrin, radixin, moesin and the coupling of membranes to the actin cytoskeleton: a smoking gun? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:643-57. [PMID: 23732235 DOI: 10.1016/j.bbamem.2013.05.025] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 05/20/2013] [Accepted: 05/21/2013] [Indexed: 12/20/2022]
Abstract
The CLIC proteins are a highly conserved family of metazoan proteins with the unusual ability to adopt both soluble and integral membrane forms. The physiological functions of CLIC proteins may include enzymatic activity in the soluble form and anion channel activity in the integral membrane form. CLIC proteins are associated with the ERM proteins: ezrin, radixin and moesin. ERM proteins act as cross-linkers between membranes and the cortical actin cytoskeleton. Both CLIC and ERM proteins are controlled by Rho family small GTPases. CLIC proteins, ERM and Rho GTPases act in a concerted manner to control active membrane processes including the maintenance of microvillar structures, phagocytosis and vesicle trafficking. All of these processes involve the interaction of membranes with the underlying cortical actin cytoskeleton. The relationships between Rho GTPases, CLIC proteins, ERM proteins and the membrane:actin cytoskeleton interface are reviewed. Speculative models are proposed involving the formation of localised multi-protein complexes on the membrane surface that assemble via multiple weak interactions. This article is part of a Special Issue entitled: Reciprocal influences between cell cytoskeleton and membrane channels, receptors and transporters. Guest Editor: Jean Claude Hervé.
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Affiliation(s)
- Lele Jiang
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW 2010, Australia
| | - Juanita M Phang
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Jiang Yu
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Stephen J Harrop
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Anna V Sokolova
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, Australia
| | - Anthony P Duff
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, Australia
| | - Krystyna E Wilk
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Heba Alkhamici
- School of Medical and Molecular Biosciences, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Samuel N Breit
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW 2010, Australia
| | - Stella M Valenzuela
- School of Medical and Molecular Biosciences, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Louise J Brown
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Paul M G Curmi
- St Vincent's Centre for Applied Medical Research, St Vincent's Hospital, Sydney, NSW 2010, Australia; School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia.
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27
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Maniti O, Carvalho K, Picart C. Model membranes to shed light on the biochemical and physical properties of ezrin/radixin/moesin. Biochimie 2013; 95:3-11. [PMID: 23041444 PMCID: PMC4112940 DOI: 10.1016/j.biochi.2012.09.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Accepted: 09/28/2012] [Indexed: 10/27/2022]
Abstract
Ezrin, radixin and moesin (ERM) proteins are now more and more recognized to play a key role in a large number of important physiological processes such as morphogenesis, cancer metastasis and virus infection. Several recent reviews extensively discuss their biological functions [1 -4 ]. In this review, we will first remind the main features of this family of proteins, which are now known as linkers and regulators of the plasma membrane/cytoskeleton linkage. We will then briefly review their implication in pathological processes such as cancer and viral infection. In a second part, we will focus on biochemical and biophysical approaches to study ERM interaction with lipid membranes and conformational change in well-defined environments. In vitro studies using biomimetic lipid membranes, especially large unilamellar vesicles (LUVs), giant unilamellar vesicles (GUVs) and supported lipid bilayers (SLBs) and recombinant proteins help to understand the molecular mechanism of conformational activation of ERM proteins. These tools are aimed to decorticate the different steps of the interaction, to simplify the experiments performed in vivo in much more complex biological environments.
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Affiliation(s)
- Ofélia Maniti
- CNRS UMR 5628 (LMGP), Grenoble Institute of Technology and CNRS, 3 parvis Louis Néel, F-38016 Grenoble Cedex, France
- Institut de Chimie et de Biochimie Moléculaires et Supramoléculaires, UMR 5246, CNRS, Université de Lyon, Université Lyon 1, INSA-Lyon, CPE-Lyon, 43 Bd du 11 Novembre 1918, F-69622 Villeurbanne, France
| | - Kevin Carvalho
- Institut Curie, centre de recherche and CNRS UMR 168, 11 rue Pierre et Marie Curie, Paris, F-75248 cedex 5
| | - Catherine Picart
- CNRS UMR 5628 (LMGP), Grenoble Institute of Technology and CNRS, 3 parvis Louis Néel, F-38016 Grenoble Cedex, France
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28
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Maniti O, Khalifat N, Goggia K, Dalonneau F, Guérin C, Blanchoin L, Ramos L, Picart C. Binding of moesin and ezrin to membranes containing phosphatidylinositol (4,5) bisphosphate: a comparative study of the affinity constants and conformational changes. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1818:2839-49. [PMID: 22813867 PMCID: PMC4111548 DOI: 10.1016/j.bbamem.2012.07.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Revised: 06/20/2012] [Accepted: 07/09/2012] [Indexed: 11/28/2022]
Abstract
The plasma membrane-cytoskeleton interface is a dynamic structure participating in a variety of cellular events. Moesin and ezrin, proteins from the ezrin/radixin/moesin (ERM) family, provide a direct linkage between the cytoskeleton and the membrane via their interaction with phosphatidylinositol 4,5-bisphosphate (PIP(2)). PIP(2) binding is considered as a prerequisite step in ERM activation. The main objective of this work was to compare moesin and ezrin interaction with PIP(2)-containing membranes in terms of affinity and to analyze secondary structure modifications leading eventually to ERM activation. For this purpose, we used two types of biomimetic model membranes, large and giant unilamellar vesicles. The dissociation constant between moesin and PIP(2)-containing large unilamellar vesicles or PIP(2)-containing giant unilamellar vesicles was found to be very similar to that between ezrin and PIP(2)-containing large unilamellar vesicles or PIP(2)-containing giant unilamellar vesicles. In addition, both proteins were found to undergo conformational changes after binding to PIP(2)-containing large unilamellar vesicles. Changes were evidenced by an increased sensitivity to proteolysis, modifications in the fluorescence intensity of the probe attached to the C-terminus and in the proportion of secondary structure elements.
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Affiliation(s)
- Ofelia Maniti
- Grenoble Institute of Technology and CNRS, Grenoble Cedex, France
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29
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Yogesha SD, Sharff AJ, Giovannini M, Bricogne G, Izard T. Unfurling of the band 4.1, ezrin, radixin, moesin (FERM) domain of the merlin tumor suppressor. Protein Sci 2011; 20:2113-20. [PMID: 22012890 DOI: 10.1002/pro.751] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 10/07/2011] [Indexed: 12/30/2022]
Abstract
The merlin-1 tumor suppressor is encoded by the Neurofibromatosis-2 (Nf2) gene and loss-of-function Nf2 mutations lead to nervous system tumors in man and to several tumor types in mice. Merlin is an ERM (ezrin, radixin, moesin) family cytoskeletal protein that interacts with other ERM proteins and with components of cell-cell adherens junctions (AJs). Merlin stabilizes the links of AJs to the actin cytoskeleton. Thus, its loss destabilizes AJs, promoting cell migration and invasion, which in Nf2(+/-) mice leads to highly metastatic tumors. Paradoxically, the "closed" conformation of merlin-1, where its N-terminal four-point-one, ezrin, radixin, moesin (FERM) domain binds to its C-terminal tail domain, directs its tumor suppressor functions. Here we report the crystal structure of the human merlin-1 head domain when crystallized in the presence of its tail domain. Remarkably, unlike other ERM head-tail interactions, this structure suggests that binding of the tail provokes dimerization and dynamic movement and unfurling of the F2 motif of the FERM domain. We conclude the "closed" tumor suppressor conformer of merlin-1 is in fact an "open" dimer whose functions are disabled by Nf2 mutations that disrupt this architecture.
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Affiliation(s)
- S D Yogesha
- Cell Adhesion Laboratory, Department of Cancer Biology, The Scripps Research Institute, Jupiter, Florida 33458, USA
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30
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Structural basis of cargo recognition by the myosin-X MyTH4-FERM domain. EMBO J 2011; 30:2734-47. [PMID: 21642953 PMCID: PMC3155308 DOI: 10.1038/emboj.2011.177] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Accepted: 05/06/2011] [Indexed: 11/26/2022] Open
Abstract
Myosin-X is implicated in spindle assembly and filopodial transport. A detailed structure function analysis of the myosin-X tail domain in association with a cargo involved in axonal pathfinding, the netrin receptor DCC and competitive binding to integrin β5 and microtubules is presented. Myosin-X is an important unconventional myosin that is critical for cargo transportation to filopodia tips and is also utilized in spindle assembly by interacting with microtubules. We present a series of structural and biochemical studies of the myosin-X tail domain cassette, consisting of myosin tail homology 4 (MyTH4) and FERM domains in complex with its specific cargo, a netrin receptor DCC (deleted in colorectal cancer). The MyTH4 domain is folded into a helical VHS-like structure and is associated with the FERM domain. We found an unexpected binding mode of the DCC peptide to the subdomain C groove of the FERM domain, which is distinct from previously reported β–β associations found in radixin–adhesion molecule complexes. We also revealed direct interactions between the MyTH4–FERM cassette and tubulin C-terminal acidic tails, and identified a positively charged patch of the MyTH4 domain, which is involved in tubulin binding. We demonstrated that both DCC and integrin bindings interfere with microtubule binding and that DCC binding interferes with integrin binding. Our results provide the molecular basis by which myosin-X facilitates alternative dual binding to cargos and microtubules.
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31
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Arpin M, Chirivino D, Naba A, Zwaenepoel I. Emerging role for ERM proteins in cell adhesion and migration. Cell Adh Migr 2011; 5:199-206. [PMID: 21343695 DOI: 10.4161/cam.5.2.15081] [Citation(s) in RCA: 177] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The highly related ERM (Ezrin, Radixin, Moesin) proteins provide a regulated linkage between the membrane and the underlying actin cytoskeleton. They also provide a platform for the transmission of signals in responses to extracellular cues. Studies in different model organisms and in cultured cells have highlighted the importance of ERM proteins in the generation and maintenance of specific domains of the plasma membrane. A central question is how do ERM proteins coordinate actin filament organization and membrane protein transport/stability with signal transduction pathways to build up complex structures? Through their interaction with numerous partners including membrane proteins, actin cytoskeleton and signaling molecules, ERM proteins have the ability to organize multiprotein complexes in specific cellular compartments. Likewise, ERM proteins participate in diverse functions including cell morphogenesis, endocytosis/exocytosis, adhesion and migration. This review focuses on aspects still poorly understood related to the function of ERM proteins in epithelial cell adhesion and migration.
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Affiliation(s)
- Monique Arpin
- UMR 144, Centre National de la Recherche Scientifique/Morphogenèse et Signalisation Cellulaires, Institut Curie, Paris, France.
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32
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Zawawi KH, Kantarci A, Schulze-Späte U, Fujita T, Batista EL, Amar S, Van Dyke TE. Moesin-induced signaling in response to lipopolysaccharide in macrophages. J Periodontal Res 2010; 45:589-601. [PMID: 20546116 DOI: 10.1111/j.1600-0765.2010.01271.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND OBJECTIVE Many physiological and pathophysiological conditions are attributable in part to cytoskeletal regulation of cellular responses to signals. Moesin (membrane-organizing extension spike protein), an ERM (ezrin, radixin and moesin) family member, is involved in lipopolysaccharide (LPS)-mediated events in mononuclear phagocytes; however, its role in signaling is not fully understood. The aim of this study was to investigate the LPS-induced moesin signaling pathways in macrophages. MATERIAL AND METHODS Macrophages were stimulated with 500 ng/mL LPS in macrophage serum-free medium. For blocking experiments, cells were pre-incubated with anti-moesin antibody. Moesin total protein and phosphorylation were studied with western blotting. Moesin mRNA was assessed using quantitative real-time PCR. To explore binding of moesin to LPS, native polyacrylamide gel electrophoresis (PAGE) gel shift assay was performed. Moesin immunoprecipitation with CD14, MD-2 and Toll-like receptor 4 (TLR4) and co-immunoprecipitation of MyD88-interleukin-1 receptor-associated kinase (IRAK) and IRAK-tumor necrosis factor receptor-activated factor 6 (TRAF6) were analyzed. Phosphorylation of IRAK and activities of MAPK, nuclear factor kappaB (NF-kappaB) and IkappaBalpha were studied. Tumor necrosis factor alpha, interleukin-1beta and interferon beta were measured by ELISA. RESULTS Moesin was identified as part of a protein cluster that facilitates LPS recognition and results in the expression of proinflammatory cytokines. Lipopolysaccharide stimulates moesin expression and phosphorylation by binding directly to the moesin carboxyl-terminus. Moesin is temporally associated with TLR4 and MD-2 after LPS stimulation, while CD14 is continuously bound to moesin. Lipopolysaccharide-induced signaling is transferred downstream to p38, p44/42 MAPK and NF-kappaB activation. Blockage of moesin function interrupts the LPS response through an inhibition of MyD88, IRAK and TRAF6, negatively affecting subsequent activation of the MAP kinases (p38 and ERK), NF-kappaB activation and translocation to the nucleus. CONCLUSION These results suggest an important role for moesin in the innate immune response and TLR4-mediated pattern recognition in periodontal disease.
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Affiliation(s)
- K H Zawawi
- Department of Preventive Dental Science, Division of Orthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
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Fehon RG, McClatchey AI, Bretscher A. Organizing the cell cortex: the role of ERM proteins. Nat Rev Mol Cell Biol 2010; 11:276-87. [PMID: 20308985 DOI: 10.1038/nrm2866] [Citation(s) in RCA: 793] [Impact Index Per Article: 56.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Specialized membrane domains are an important feature of almost all cells. In particular, they are essential to tissues that have a highly organized cell cortex, such as the intestinal brush border epithelium. The ERM proteins (ezrin, radixin and moesin) have a crucial role in organizing membrane domains through their ability to interact with transmembrane proteins and the cytoskeleton. In doing so, they can provide structural links to strengthen the cell cortex and regulate the activities of signal transduction pathways. Recent studies examining the structure and in vivo functions of ERMs have greatly advanced our understanding of the importance of membrane-cytoskeleton interactions.
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Affiliation(s)
- Richard G Fehon
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA.
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34
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Meurice N, Wang L, Lipinski CA, Yang Z, Hulme C, Loftus JC. Structural conservation in band 4.1, ezrin, radixin, moesin (FERM) domains as a guide to identify inhibitors of the proline-rich tyrosine kinase 2. J Med Chem 2010; 53:669-77. [PMID: 20017492 DOI: 10.1021/jm901247a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The nonreceptor focal adhesion kinases FAK and Pyk2 play a central role in the regulation of glioma cell proliferation and migration, making them attractive targets to improve clinical outcome. Noncatalytic targeting represents a novel approach to regulate the activity of these tyrosine kinases. A combination of site directed mutagenesis and molecular modeling was used to identify compounds that target the F3 module of the Pyk2 FERM domain. A protein pharmacophore model for the Pyk2 FERM/F3 module, generated utilizing the structural conservation of ligand-bound FERM domains with known 3D structures, was used to search the LeadQuest compound library. Compounds compliant with the model were tested for their ability to inhibit the binding of a monoclonal antibody that maps to a functional site on the F3 module. The highest scoring compound bound directly to the Pyk2 FERM domain, inhibited Pyk2 stimulated glioma migration, and provides the framework for the development of novel therapeutic agents to target the activity of the focal adhesion kinases.
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Affiliation(s)
- Nathalie Meurice
- The Translational Genomics Research Institute, Phoenix, Arizona 85004, USA
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Abstract
IMPORTANCE OF THE FIELD The focal adhesion tyrosine kinases FAK and Pyk2 are uniquely situated to act as critical mediators for the activation of signaling pathways that regulate cell migration, proliferation and survival. By coordinating adhesion and cytoskeletal dynamics with survival and growth signaling, FAK and Pyk2 represent molecular therapeutic targets in cancer as malignant cells often exhibit defects in these processes. AREAS COVERED IN THIS REVIEW This review examines the structure and function of the focal adhesion kinase Pyk2 and intends to provide a rationale for the employment of modulating strategies that include both catalytic and extra-catalytic approaches that have been developed in the last 3 - 5 years. WHAT THE READER WILL GAIN Targeting tyrosine kinases in oncology has focused on the ATP binding pocket as means to inhibit catalytic activity and downregulate pathways involved in tumor invasion. This review discusses the available catalytic inhibitors and compares them to the alternative approach of targeting protein-protein interactions that regulate kinase activity. TAKE HOME MESSAGE Development of specific catalytic inhibitors of the focal adhesion kinases has improved but significant challenges remain. Thus, approaches that inhibit the effector function of Pyk2 by targeting regulatory modules can increase specificity and will be a welcome asset to the therapeutic arena.
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Affiliation(s)
- Christopher A Lipinski
- Mayo Clinic Collaborative Research Building, Department of Biochemistry and Molecular Biology, Scottsdale, AZ 85259, USA
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Loftus JC, Yang Z, Tran NL, Kloss J, Viso C, Berens ME, Lipinski CA. The Pyk2 FERM domain as a target to inhibit glioma migration. Mol Cancer Ther 2009; 8:1505-14. [PMID: 19509258 DOI: 10.1158/1535-7163.mct-08-1055] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The invasion of malignant glioma cells into the surrounding normal brain precludes effective clinical treatment. In this report, we investigated the role of the NH(2)-terminal FERM domain in the regulation of the promigratory function of Pyk2. We report that the substitution of residues that constitute a small cleft on the surface of the F3 module of the FERM domain do not significantly alter Pyk2 expression but result in the loss of Pyk2 phosphorylation. A monoclonal antibody, designated 12A10, specifically targeting the Pyk2 FERM domain was generated and recognizes an epitope located on the beta5C-alpha1C surface of the F3 module of the FERM domain. Amino acid substitutions in the F3 module that resulted in the loss of Pyk2 phosphorylation also inhibited the binding of 12A10, suggesting that the 12A10 epitope overlaps a site that plays a role in Pyk2 activity. Conjugation of 12A10 to a membrane transport peptide led to intracellular accumulation and inhibition of glioma cell migration in a concentration-dependent manner. A single chain Fv fragment of 12A10 was stable when expressed in the intracellular environment, interacted directly with Pyk2, reduced Pyk2 phosphorylation, and inhibited glioma cell migration in vitro. Stable intracellular expression of the 12A10 scFv significantly extended survival in a glioma xenograft model. Together, these data substantiate a central role for the FERM domain in regulation of Pyk2 activity and identify the F3 module as a novel target to inhibit Pyk2 activity and inhibit glioma progression.
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Affiliation(s)
- Joseph C Loftus
- Mayo Clinic Arizona, 13400 East Shea Boulevard, Scottsdale, AZ 85259, USA.
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37
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Killock DJ, Parsons M, Zarrouk M, Ameer-Beg SM, Ridley AJ, Haskard DO, Zvelebil M, Ivetic A. In Vitro and in Vivo Characterization of Molecular Interactions between Calmodulin, Ezrin/Radixin/Moesin, and L-selectin. J Biol Chem 2009; 284:8833-45. [PMID: 19129194 PMCID: PMC2659241 DOI: 10.1074/jbc.m806983200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
L-selectin is a cell adhesion molecule that tethers leukocytes to the
luminal walls of venules during inflammation and enables them to roll under
the force of blood flow. Clustering of L-selectin during rolling is thought to
promote outside-in signals that lead to integrin activation and chemokine
receptor expression, ultimately contributing to leukocyte arrest. Several
studies have underscored the importance of the L-selectin cytoplasmic tail in
functionally regulating adhesion and signaling. Interestingly, the L-selectin
tail comprises only 17 amino acids, and yet it is thought to bind
simultaneously to several proteins. For example, constitutive association of
calmodulin (CaM) and ezrin/radixin/moesin (ERM) to L-selectin confers
resistance to proteolysis and microvillar positioning, respectively. In this
report we found that recombinant purified CaM and ERM bound non-competitively
to the same tail of L-selectin. Furthermore, molecular modeling supported the
possibility that CaM, L-selectin, and moesin could form a heterotrimeric
complex. Finally, using fluorescence lifetime imaging microscopy to measure
fluorescence resonance energy transfer, it was shown that CaM, L-selectin, and
ERM could interact simultaneously in vivo. Moreover, L-selectin
clustering promoted CaM/ERM interaction in cis (i.e. derived
from neighboring L-selectin tails). These results highlight a novel
intracellular event that occurs as a consequence of L-selectin clustering,
which could participate in transducing signals that promote the transition
from rolling to arrest.
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Affiliation(s)
- David J Killock
- Cardiovascular Science Unit, National Heart and Lung Institute, Imperial College London, Hammersmith Campus, London W12 0NN
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Liu D, Ge L, Wang F, Takahashi H, Wang D, Guo Z, Yoshimura SH, Ward T, Ding X, Takeyasu K, Yao X. Single-molecule detection of phosphorylation-induced plasticity changes during ezrin activation. FEBS Lett 2007; 581:3563-71. [PMID: 17628548 DOI: 10.1016/j.febslet.2007.06.071] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2007] [Revised: 06/05/2007] [Accepted: 06/26/2007] [Indexed: 11/21/2022]
Abstract
Ezrin-radixin-moesin protein family provides a regulated link between the cortical actin cytoskeleton and the plasma membrane. Phosphorylation of ezrin has been functionally linked to membrane dynamics and plasticity. Our recent study demonstrated that phosphorylation of the conserved T567 residue of ezrin alters the physiology of gastric parietal cells. However, the molecular mechanism of phosphorylation-induced ezrin activation has remained elusive. Here we use atomic force microscopy (AFM) to probe phosphorylation-mediated activation of ezrin in single molecules. The phospho-mimicking and non-phosphorylatable mutant ezrin proteins were generated and purified to homogeneity. Comparative analyses of two ezrin mutants by AFM demonstrate the unfolding of the N- and C-terminal domains upon the phospho-activation. To measure the physical force underlying the inter-domain contact during mechanical unfolding, we probed the defined region of ezrin using the N-terminal ezrin coated onto the AFM tip. Comparative force measurements indicate that T567 phosphorylation-induced unfolding of ezrin favors the inter-molecular association. Taken together, these results provide molecular illustration of phosphorylation elicited functional activation of ERM proteins and indicate that stimulus-induced protein conformational change can be used as a signaling mechanism orchestrating cellular dynamics.
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Affiliation(s)
- Dan Liu
- Division of Cellular Dynamics, Hefei National Laboratory for Physical Sciences, Hefei 230027, China
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Abstract
NHE3 is the brush-border (BB) Na+/H+exchanger of small intestine, colon, and renal proximal tubule which is involved in large amounts of neutral Na+absorption. NHE3 is a highly regulated transporter, being both stimulated and inhibited by signaling that mimics the postprandial state. It also undergoes downregulation in diarrheal diseases as well as changes in renal disorders. For this regulation, NHE3 exists in large, multiprotein complexes in which it associates with at least nine other proteins. This review deals with short-term regulation of NHE3 and the identity and function of its recognized interacting partners and the multiprotein complexes in which NHE3 functions.
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Affiliation(s)
- Mark Donowitz
- Department of Medicine, GI Division, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
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40
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Im E, Kazlauskas A. PtdIns-4,5-P2 as a potential therapeutic target for pathologic angiogenesis. Expert Opin Ther Targets 2007; 11:443-51. [PMID: 17373875 DOI: 10.1517/14728222.11.4.443] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A variety of diseases arise, at least in part, when the events controlling the formation and stability of blood vessels are deregulated. For instance, the growth and survival of solid tumors are tightly linked to their ability to undergo vascularization. Similarly, pathologic angiogenesis of the retina or choroid underscores blinding diseases that afflict a substantial percentage of the world's population. Therefore, it is of great interest to develop antiangiogenic drugs that will relieve the burden of vascular diseases such as cancer, age-related macular degeneration and proliferative diabetic retinopathy. In this article, the authors highlight their recent discovery that PtdIns-4,5-P2)can regulate vessel stability. This finding identifies PtdIns-4,5-P2 as a novel target for angiogenesis therapies.
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Affiliation(s)
- Eunok Im
- Schepens Eye Research Institute, Harvard Medical School, 20 Staniford Street, Boston, MA 02114, USA
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Wegener KL, Partridge AW, Han J, Pickford AR, Liddington RC, Ginsberg MH, Campbell ID. Structural basis of integrin activation by talin. Cell 2007; 128:171-82. [PMID: 17218263 DOI: 10.1016/j.cell.2006.10.048] [Citation(s) in RCA: 498] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2006] [Revised: 09/05/2006] [Accepted: 10/20/2006] [Indexed: 02/04/2023]
Abstract
Regulation of integrin affinity (activation) is essential for metazoan development and for many pathological processes. Binding of the talin phosphotyrosine-binding (PTB) domain to integrin beta subunit cytoplasmic domains (tails) causes activation, whereas numerous other PTB-domain-containing proteins bind integrins without activating them. Here we define the structure of a complex between talin and the membrane-proximal integrin beta3 cytoplasmic domain and identify specific contacts between talin and the integrin tail required for activation. We used structure-based mutagenesis to engineer talin and beta3 variants that interact with comparable affinity to the wild-type proteins but inhibit integrin activation by competing with endogenous talin. These results reveal the structural basis of talin's unique ability to activate integrins, identify an interaction that could aid in the design of therapeutics to block integrin activation, and enable engineering of cells with defects in the activation of multiple classes of integrins.
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Affiliation(s)
- Kate L Wegener
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, England, UK
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42
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Li Q, Nance MR, Kulikauskas R, Nyberg K, Fehon R, Karplus PA, Bretscher A, Tesmer JJG. Self-masking in an intact ERM-merlin protein: an active role for the central alpha-helical domain. J Mol Biol 2006; 365:1446-59. [PMID: 17134719 PMCID: PMC1796844 DOI: 10.1016/j.jmb.2006.10.075] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 10/16/2006] [Accepted: 10/18/2006] [Indexed: 01/11/2023]
Abstract
Ezrin/radixin/moesin (ERM) family members provide a regulated link between the cortical actin cytoskeleton and the plasma membrane to govern membrane structure and organization. Here, we report the crystal structure of intact insect moesin, revealing that its essential yet previously uncharacterized alpha-helical domain forms extensive interactions with conserved surfaces of the band four-point-one/ezrin/radixin/moesin (FERM) domain. These interdomain contacts provide a functional explanation for how PIP(2) binding and tyrosine phosphorylation of ezrin lead to activation, and provide an understanding of previously enigmatic loss-of-function missense mutations in the tumor suppressor merlin. Sequence conservation and biochemical results indicate that this structure represents a complete model for the closed state of all ERM-merlin proteins, wherein the central alpha-helical domain is an active participant in an extensive set of inhibitory interactions that can be unmasked, in a rheostat-like manner, by coincident regulatory factors that help determine cell polarity and membrane structure.
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Affiliation(s)
- Qianzhi Li
- Department of Chemistry and Biochemistry, Institute for Cellular and Molecular Biology, The University of Texas at Austin 1 University Station #A5300, Austin, TX 78712-0165, USA
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43
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Lipinski CA, Tran NL, Dooley A, Pang YP, Rohl C, Kloss J, Yang Z, McDonough W, Craig D, Berens ME, Loftus JC. Critical role of the FERM domain in Pyk2 stimulated glioma cell migration. Biochem Biophys Res Commun 2006; 349:939-47. [PMID: 16962067 DOI: 10.1016/j.bbrc.2006.08.134] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Accepted: 08/17/2006] [Indexed: 10/24/2022]
Abstract
The strong tendency of malignant glioma cells to invade locally into surrounding normal brain precludes effective surgical resection, reduces the efficacy of radiotherapy, and is associated with increased resistance to chemotherapy regimens. We report that the N-terminal FERM domain of Pyk2 regulates its promigratory function. A 3-dimensional model of the Pyk2 FERM domain was generated and mutagenesis studies identified residues essential for Pyk2 promigratory function. Model-based targeted mutations within the FERM domain decreased Pyk2 phosphorylation and reduced the capacity of Pyk2 to stimulate glioma cell migration but did not significantly alter the intracellular distribution of Pyk2. Expression of autonomous Pyk2 FERM domain fragments containing analogous mutations exhibited reduced capacity to inhibit glioma cell migration and Pyk2 phosphorylation relative to expression of an autonomous wild type FERM domain fragment. These results indicate that the FERM domain plays an important role in regulating the functional competency of Pyk2 as a promigratory factor in glioma.
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44
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Fiévet B, Louvard D, Arpin M. ERM proteins in epithelial cell organization and functions. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1773:653-60. [PMID: 16904765 DOI: 10.1016/j.bbamcr.2006.06.013] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2006] [Revised: 05/18/2006] [Accepted: 06/30/2006] [Indexed: 11/17/2022]
Abstract
ERM (Ezrin, Radixin, Moesin) proteins are membrane-cytoskeleton linkers that regulate the structure and the function of specific domains of the plasma membrane. ERM proteins are expressed in all metazoan analyzed so far. Genetic analysis of ERM protein functions has recently been performed simultaneously in three different organisms, mouse, Drosophila melanogaster and C. elegans. These studies have revealed a remarkable conservation of the protein functions through evolution. Moreover they have shed light on the crucial role these proteins play in various physiological processes that occur in epithelial cells.
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Affiliation(s)
- Bruno Fiévet
- UMR 144 CNRS-Institut Curie 26 rue d'Ulm, 75248 PARIS cedex 05, France
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45
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Kitano K, Yusa F, Hakoshima T. Structure of dimerized radixin FERM domain suggests a novel masking motif in C-terminal residues 295-304. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:340-5. [PMID: 16582480 PMCID: PMC2222584 DOI: 10.1107/s1744309106010062] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Accepted: 03/18/2006] [Indexed: 01/19/2023]
Abstract
ERM (ezrin/radixin/moesin) proteins bind to the cytoplasmic tail of adhesion molecules in the formation of the membrane-associated cytoskeleton. The binding site is located in the FERM (4.1 and ERM) domain, a domain that is masked in the inactive form. A conventional masking motif, strand 1 (residues 494-500 in radixin), has previously been identified in the C-terminal tail domain. Here, the crystal structure of dimerized radixin FERM domains (residues 1-310) is presented in which the binding site of one molecule is occupied by the C-terminal residues (residues 295-304, strand 2) of the other molecule. The residues contain a conserved motif that is compatible with that identified in the adhesion molecules. The residues might serve as a second masking region in the inactive form of ERM proteins.
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Affiliation(s)
- Ken Kitano
- Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Fumie Yusa
- Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Toshio Hakoshima
- Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
- CREST, Japan Science and Technology Agency, Japan
- Correspondence e-mail:
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46
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Abstract
The acquisition of a cell polarity is a crucial requirement for a number of cellular functions, including apoptosis. Cell polarization is an actin cytoskeleton-driven process, through a connection between actin and an increasing number of membrane proteins. The major actors in this connection are ezrin, radixin and moesin, a family of proteins with a high level of homology. Their structure includes an epitope that links to membrane proteins and the other that binds to the actin molecule. In this review we discuss recent data showing that the Fas linkage to the actin cytoskeleton is ezrin mediated and it is an essential requirement for susceptibility to the Fas-mediated apoptosis. The ezrin region responsible of Fas binding consists of 18 aminoacids mapped on the median lobe of the ezrin FERM domain. This binding is specific and of key importance in the control of cell homeostasis. Moreover, Fas-ezrin co-localization, ezrin phosphorylation and early acquisition of susceptibility to Fas-mediated apoptosis, may have a role in some human diseases in which programmed cell death seems to be a central pathogenetic mechanism, such as AIDS.
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Affiliation(s)
- S Fais
- Department of Drug Research and Evaluation, Pharmacogenetic, Drug Resistance and Experimental Therapeutic Section, Istituto Superiore di Sanità, Rome 00161, Italy.
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47
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McRobert EA, Tikoo A, Gallicchio MA, Cooper ME, Bach LA. Localization of the Ezrin Binding Epitope for Glycated Proteins. Ann N Y Acad Sci 2006; 1043:617-24. [PMID: 16037285 DOI: 10.1196/annals.1333.070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
ERM proteins (ezrin, radixin, and moesin) have recently been identified as a new class of AGE-binding proteins. ERM proteins link the plasma membrane with the actin cytoskeleton and regulate cell shape, motility, adhesion, and signal transduction. ERM proteins have three structural domains: the N-terminal domain, a coiled midregion, and the C-terminal domain. The N-terminal domain binds to a number of plasma membrane ligands and is involved in signal transduction, while the C-domain binds to actin filaments. Binding studies with isolated structural domains showed that glycated proteins bind to an epitope within the N-terminal domain of ezrin (aa 1-324). It is postulated that some of the cellular effects of AGEs leading to diabetic complications may be mediated by binding to this region of ezrin, thereby interrupting the cross-linking between the plasma membrane and actin cytoskeleton and downstream signaling pathways. Indeed, changes in actin arrangement, cell shape, and adhesion have been described in diabetes, and AGE-BSA inhibits ezrin-dependent tubulogenesis of LLC-PK1 proximal tubular cells. For future development of antagonists, further identification of the ezrin-binding epitope for glycated proteins is required.
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Affiliation(s)
- E Anne McRobert
- Present address and address for correspondence: E. Anne McRobert, Central and Eastern Clinical School, Department of Medicine, Monash University, AMREP, Alfred Hospital, Prahran, Vic 3181, Australia.
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48
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Ceccarelli DFJ, Song HK, Poy F, Schaller MD, Eck MJ. Crystal Structure of the FERM Domain of Focal Adhesion Kinase. J Biol Chem 2006; 281:252-9. [PMID: 16221668 DOI: 10.1074/jbc.m509188200] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that localizes to focal adhesions in adherent cells. Through phosphorylation of proteins assembled at the cytoplasmic tails of integrins, FAK promotes signaling events that modulate cellular growth, survival, and migration. The amino-terminal region of FAK contains a region of sequence homology with band 4.1 and ezrin/radixin/moesin (ERM) proteins termed a FERM domain. FERM domains are found in a variety of signaling and cytoskeletal proteins and are thought to mediate intermolecular interactions with partner proteins and phospholipids at the plasma membrane and intramolecular regulatory interactions. Here we report two crystal structures of an NH2-terminal fragment of avian FAK containing the FERM domain and a portion of the regulatory linker that connects the FERM and kinase domains. The tertiary folds of the three subdomains (F1, F2, and F3) are similar to those of known FERM structures despite low sequence conservation. Differences in the sequence and relative orientation of the F3 subdomain alters the nature of the interdomain interface, and the phosphoinositide binding site found in ERM family FERM domains is not present in FAK. A putative protein interaction site on the F3 lobe is masked by the proximal region of the linker. Additionally, in one structure the adjacent Src SH3 and SH2 binding sites in the linker associate with the surfaces of the F3 and F1 lobes, respectively. These structural features suggest the possibility that protein interactions of the FAK FERM domain can be regulated by binding of Src kinases to the linker segment.
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Affiliation(s)
- Derek F J Ceccarelli
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA
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49
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Golovnina K, Blinov A, Akhmametyeva EM, Omelyanchuk LV, Chang LS. Evolution and origin of merlin, the product of the Neurofibromatosis type 2 (NF2) tumor-suppressor gene. BMC Evol Biol 2005; 5:69. [PMID: 16324214 PMCID: PMC1315344 DOI: 10.1186/1471-2148-5-69] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2005] [Accepted: 12/02/2005] [Indexed: 11/10/2022] Open
Abstract
Background Merlin, the product of the Neurofibromatosis type 2 (NF2) tumor suppressor gene, belongs to the ezrin-radixin-moesin (ERM) subgroup of the protein 4.1 superfamily, which links cell surface glycoproteins to the actin cytoskeleton. While merlin's functional activity has been examined in mammalian and Drosophila models, little is understood about its evolution, diversity, and overall distribution among different taxa. Results By combining bioinformatic and phylogenetic approaches, we demonstrate that merlin homologs are present across a wide range of metazoan lineages. While the phylogenetic tree shows a monophyletic origin of the ERM family, the origin of the merlin proteins is robustly separated from that of the ERM proteins. The derivation of merlin is thought to be in early metazoa. We have also observed the expansion of the ERM-like proteins within the vertebrate clade, which occurred after its separation from Urochordata (Ciona intestinalis). Amino acid sequence alignment reveals the absence of an actin-binding site in the C-terminal region of all merlin proteins from various species but the presence of a conserved internal binding site in the N-terminal domain of the merlin and ERM proteins. In addition, a more conserved pattern of amino acid residues is found in the region containing the so-called "Blue Box," although some amino acid substitutions in this region exist in the merlin sequences of worms, fish, and Ciona. Examination of sequence variability at functionally significant sites, including the serine-518 residue, the phosphorylation of which modulates merlin's intra-molecular association and function as a tumor suppressor, identifies several potentially important sites that are conserved among all merlin proteins but divergent in the ERM proteins. Secondary structure prediction reveals the presence of a conserved α-helical domain in the central to C-terminal region of the merlin proteins of various species. The conserved residues and structures identified correspond to the important sites highlighted by the available crystal structures of the merlin and ERM proteins. Furthermore, analysis of the merlin gene structures from various organisms reveals the increase of gene length during evolution due to the expansion of introns; however, a reduction of intron number and length appears to occur in the merlin gene of the insect group. Conclusion Our results demonstrate a monophyletic origin of the merlin proteins with their root in the early metazoa. The overall similarity among the primary and secondary structures of all merlin proteins and the conservation of several functionally important residues suggest a universal role for merlin in a wide range of metazoa.
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Affiliation(s)
- Kseniya Golovnina
- Institute of Cytology and Genetics, Russian Academy of Sciences, 10 Lavrent'ev Ave., 630090, Novosibirsk, Russia
| | - Alexander Blinov
- Institute of Cytology and Genetics, Russian Academy of Sciences, 10 Lavrent'ev Ave., 630090, Novosibirsk, Russia
| | - Elena M Akhmametyeva
- Center for Childhood Cancer, Children's Research Institute, Children's Hospital and Department of Pediatrics, The Ohio State University, 700 Children's Drive, Columbus, OH 43205-2696, USA
| | - Leonid V Omelyanchuk
- Institute of Cytology and Genetics, Russian Academy of Sciences, 10 Lavrent'ev Ave., 630090, Novosibirsk, Russia
| | - Long-Sheng Chang
- Center for Childhood Cancer, Children's Research Institute, Children's Hospital and Department of Pediatrics, The Ohio State University, 700 Children's Drive, Columbus, OH 43205-2696, USA
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50
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Abstract
Research in the past decade has revealed that many cytosolic proteins are recruited to different cellular membranes to form protein-protein and lipid-protein interactions during cell signaling and membrane trafficking. Membrane recruitment of these peripheral proteins is mediated by a growing number of modular membrane-targeting domains, including C1, C2, PH, FYVE, PX, ENTH, ANTH, BAR, FERM, and tubby domains, that recognize specific lipid molecules in the membranes. Structural studies of these membrane-targeting domains demonstrate how they specifically recognize their cognate lipid ligands. However, the mechanisms by which these domains and their host proteins are recruited to and interact with various cell membranes are only beginning to unravel with recent computational studies, in vitro membrane binding studies using model membranes, and cellular translocation studies using fluorescent protein-tagged proteins. This review summarizes the recent progress in our understanding of how the kinetics and energetics of membrane-protein interactions are regulated during the cellular membrane targeting and activation of peripheral proteins.
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Affiliation(s)
- Wonhwa Cho
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607-7061, USA.
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