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Li YY, Murai K, Lyu J, Honda M. Roles Played by DOCK11, a Guanine Nucleotide Exchange Factor, in HBV Entry and Persistence in Hepatocytes. Viruses 2024; 16:745. [PMID: 38793626 PMCID: PMC11125634 DOI: 10.3390/v16050745] [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: 04/01/2024] [Revised: 04/28/2024] [Accepted: 05/05/2024] [Indexed: 05/26/2024] Open
Abstract
HBV infection is challenging to cure due to the persistence of viral covalently closed circular viral DNA (cccDNA). The dedicator of cytokinesis 11 (DOCK11) is recognized as a guanine nucleotide exchange factor (GEF) for CDC42 that has been reported to be required for HBV persistence. DOCK11 is expressed in both the cytoplasm and nucleus of human hepatocytes and is functionally associated with retrograde trafficking proteins Arf-GAP with GTPase domain, ankyrin repeat, and pleckstrin homology domain-containing protein 2 (AGAP2), and ADP-ribosylation factor 1 (ARF1), together with the HBV capsid, in the trans-Golgi network (TGN). This opens an alternative retrograde trafficking route for HBV from early endosomes (EEs) to the TGN and then to the endoplasmic reticulum (ER), thereby avoiding lysosomal degradation. DOCK11 also facilitates the association of cccDNA with H3K4me3 and RNA Pol II for activating cccDNA transcription. In addition, DOCK11 plays a crucial role in the host DNA repair system, being essential for cccDNA synthesis. This function can be inhibited by 10M-D42AN, a novel DOCK11-binding peptide, leading to the suppression of HBV replication both in vitro and in vivo. Treatment with a combination of 10M-D42AN and entecavir may represent a promising therapeutic strategy for patients with chronic hepatitis B (CHB). Consequently, DOCK11 may be seen as a potential candidate molecule in the development of molecularly targeted drugs against CHB.
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Affiliation(s)
- Ying-Yi Li
- Department of Gastroenterology, Kanazawa University Graduate School of Medicine, 13-1, Takaramachi, Kanazawa 920-8640, Japan
| | - Kazuhisa Murai
- Department of Clinical Laboratory Medicine, Kanazawa University Graduate School of Health Medicine, 13-1, Takaramachi, Kanazawa 920-8640, Japan
| | - Junyan Lyu
- Department of Clinical Laboratory Medicine, Kanazawa University Graduate School of Health Medicine, 13-1, Takaramachi, Kanazawa 920-8640, Japan
| | - Masao Honda
- Department of Gastroenterology, Kanazawa University Graduate School of Medicine, 13-1, Takaramachi, Kanazawa 920-8640, Japan
- Department of Clinical Laboratory Medicine, Kanazawa University Graduate School of Health Medicine, 13-1, Takaramachi, Kanazawa 920-8640, Japan
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Kuttikrishnan S, Prabhu KS, Khan AQ, Uddin S. Signaling networks guiding erythropoiesis. Curr Opin Hematol 2024; 31:89-95. [PMID: 38335037 DOI: 10.1097/moh.0000000000000808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
PURPOSE OF REVIEW Cytokine-mediated signaling pathways, including JAK/STAT, PI3K/AKT, and Ras/MAPK pathways, play an important role in the process of erythropoiesis. These pathways are involved in the survival, proliferation, and differentiation function of erythropoiesis. RECENT FINDINGS The JAK/STAT pathway controls erythroid progenitor differentiation, proliferation, and survival. The PI3K/AKT signaling cascade facilitates erythroid progenitor survival, proliferation, and final differentiation. During erythroid maturation, MAPK, triggered by EPO, suppresses myeloid genes, while PI3K is essential for differentiation. Pro-inflammatory cytokines activate signaling pathways that can alter erythropoiesis like EPOR-triggered signaling, including survival, differentiation, and proliferation. SUMMARY A comprehensive understanding of signaling networks is crucial for the formulation of treatment approaches for hematologic disorders. Further investigation is required to fully understand the mechanisms and interactions of these signaling pathways in erythropoiesis.
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Affiliation(s)
| | | | | | - Shahab Uddin
- Translational Research Institute
- Dermatology Institute, Academic Health System, Hamad Medical Corporation
- Laboratory of Animal Center, Qatar University, Doha, Qatar
- Department of Biosciences, Integral University, Lucknow, Uttar Pradesh, India
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3
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Pumar OYT, Zanotelli MR, Lin MCJ, Schmitt RR, Green KS, Rojas KS, Hwang IY, Cerione RA, Wilson KF. A multiprotein signaling complex sustains AKT and mTOR/S6K activity necessary for the survival of cancer cells undergoing stress. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.03.522657. [PMID: 36711811 PMCID: PMC9881951 DOI: 10.1101/2023.01.03.522657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Cancer cells encounter stresses during tumor progression and metastatic spread, however, how they survive these challenges is not fully understood. We now identify a mechanism for cancer cell survival through the discovery of a multiprotein signaling complex that includes the GTPase Cdc42, the Cdc42 GEF/effector protein Dock7, AKT, mTOR and the mTORC1 regulatory partners TSC1, TSC2, and Rheb. This pro-survival signaling complex sustains the activated state of AKT by preventing its dephosphorylation at Ser473 during serum starvation, resulting in a low but critical activation of a Raptor-independent mTOR/S6K activity. We demonstrate that the Dock7 DHR1 domain, previously of unknown function, is responsible for preserving AKT phosphorylation through an interaction requiring its C2-like motif. Collectively, these findings help address long-standing questions of how Cdc42 signals mTOR activation by elucidating the unique functions of its signaling partner Dock7 as an AKT regulator necessary for resistance to anoikis and apoptosis in cancer cells.
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Affiliation(s)
| | | | - Miao-chong Joy Lin
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Rebecca R. Schmitt
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Kai Su Green
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Katherine S. Rojas
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Irene Y. Hwang
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Richard A. Cerione
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
- Department of Chemistry, Cornell University, Ithaca, NY 14853, USA
| | - Kristin F. Wilson
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
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Alexander MS, Velinov M. DOCK3-Associated Neurodevelopmental Disorder-Clinical Features and Molecular Basis. Genes (Basel) 2023; 14:1940. [PMID: 37895289 PMCID: PMC10606569 DOI: 10.3390/genes14101940] [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: 09/11/2023] [Revised: 10/09/2023] [Accepted: 10/12/2023] [Indexed: 10/29/2023] Open
Abstract
The protein product of DOCK3 is highly expressed in neurons and has a role in cell adhesion and neuronal outgrowth through its interaction with the actin cytoskeleton and key cell signaling molecules. The DOCK3 protein is essential for normal cell growth and migration. Biallelic variants in DOCK3 associated with complete or partial loss of function of the gene were recently reported in six patients with intellectual disability and muscle hypotonia. Only one of the reported patients had congenital malformations outside of the CNS. Further studies are necessary to better determine the prevalence of DOCK3-associated neurodevelopmental disorders and the frequency of non-CNS clinical manifestations in these patients. Since deficiency of the DOCK3 protein product is now an established pathway of this neurodevelopmental condition, supplementing the deficient gene product using a gene therapy approach may be an efficient treatment strategy.
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Affiliation(s)
- Matthew S. Alexander
- Department of Pediatrics, Division of Neurology, University of Alabama at Birmingham and Children’s of Alabama, Birmingham, AL 35294, USA;
- UAB Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- UAB Civitan International Research Center (CIRC), University of Alabama at Birmingham, Birmingham, AL 35233, USA
- UAB Center for Neurodegeneration and Experimental Therapeutics (CNET), University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Milen Velinov
- Department of Pediatrics, Division of Genetics, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
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5
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Namekata K, Tsuji N, Guo X, Nishijima E, Honda S, Kitamura Y, Yamasaki A, Kishida M, Takeyama J, Ishikawa H, Shinozaki Y, Kimura A, Harada C, Harada T. Neuroprotection and axon regeneration by novel low-molecular-weight compounds through the modification of DOCK3 conformation. Cell Death Discov 2023; 9:166. [PMID: 37188749 PMCID: PMC10184973 DOI: 10.1038/s41420-023-01460-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 04/26/2023] [Accepted: 05/02/2023] [Indexed: 05/17/2023] Open
Abstract
Dedicator of cytokinesis 3 (DOCK3) is an atypical member of the guanine nucleotide exchange factors (GEFs) and plays important roles in neurite outgrowth. DOCK3 forms a complex with Engulfment and cell motility protein 1 (Elmo1) and effectively activates Rac1 and actin dynamics. In this study, we screened 462,169 low-molecular-weight compounds and identified the hit compounds that stimulate the interaction between DOCK3 and Elmo1, and neurite outgrowth in vitro. Some of the derivatives from the hit compound stimulated neuroprotection and axon regeneration in a mouse model of optic nerve injury. Our findings suggest that the low-molecular-weight DOCK3 activators could be a potential therapeutic candidate for treating axonal injury and neurodegenerative diseases including glaucoma.
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Affiliation(s)
- Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Naoki Tsuji
- R&D Division, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Euido Nishijima
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Sari Honda
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yuta Kitamura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | | | | | - Jun Takeyama
- Biological Research Department, Daiichi Sankyo RD Novare Co., Ltd, Tokyo, Japan
| | - Hirokazu Ishikawa
- Biological Research Department, Daiichi Sankyo RD Novare Co., Ltd, Tokyo, Japan
| | - Youichi Shinozaki
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
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6
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Boland A, Côté J, Barford D. Structural biology of DOCK-family guanine nucleotide exchange factors. FEBS Lett 2023; 597:794-810. [PMID: 36271211 PMCID: PMC10152721 DOI: 10.1002/1873-3468.14523] [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: 08/24/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/09/2022]
Abstract
DOCK proteins are a family of multi-domain guanine nucleotide exchange factors (GEFs) that activate the RHO GTPases CDC42 and RAC1, thereby regulating several RHO GTPase-dependent cellular processes. DOCK proteins are characterized by the catalytic DHR2 domain (DOCKDHR2 ), and a phosphatidylinositol(3,4,5)P3 -binding DHR1 domain (DOCKDHR1 ) that targets DOCK proteins to plasma membranes. DOCK-family GEFs are divided into four subfamilies (A to D) differing in their specificities for CDC42 and RAC1, and the composition of accessory signalling domains. Additionally, the DOCK-A and DOCK-B subfamilies are constitutively associated with ELMO proteins that auto-inhibit DOCK GEF activity. We review structural studies that have provided mechanistic insights into DOCK-protein functions. These studies revealed how a conserved nucleotide sensor in DOCKDHR2 catalyses nucleotide exchange, the basis for how different DOCK proteins activate specifically CDC42 and RAC1, and sometimes both, and how up-stream regulators relieve the ELMO-mediated auto-inhibition. We conclude by presenting a model for full-length DOCK9 of the DOCK-D subfamily. The involvement of DOCK GEFs in a range of diseases highlights the importance of gaining structural insights into these proteins to better understand and specifically target them.
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Affiliation(s)
- Andreas Boland
- Department of Molecular and Cellular BiologyUniversity of GenevaSwitzerland
| | - Jean‐Francois Côté
- Montreal Clinical Research Institute (IRCM)Canada
- Department of Medicine and Department of Biochemistry and Molecular MedicineUniversité de MontréalCanada
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Roy D, Sengupta D, Kulkarni K. Substrate induced dynamical remodeling of the binding pocket generates GTPase specificity in DOCK family of guanine nucleotide exchange factors. Biochem Biophys Res Commun 2022; 631:32-40. [PMID: 36162327 DOI: 10.1016/j.bbrc.2022.09.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 09/14/2022] [Accepted: 09/14/2022] [Indexed: 11/17/2022]
Abstract
Dedicator of cytokinesis (DOCK) family of guanine nucleotide exchange factors (GEFs) activate two members of Rho family GTPases, Rac1/Cdc42, to exert diverse cellular processes, including cell migration. As DOCK GEFs have been critically implicated in tumour cell migration, understanding their function and specificity is imperative for designing anti-metastatic drugs. Based on their GTPase specificity they have been classified as Rac, Cdc42 and dual specific GEFs. Despite extensive structural studies, the factors that determine GTPase specificity of DOCK GEFs have remained elusive. Here, we show that subtle dynamical coupling between GEF and GTPase structures modulate the binding interface to generate mutual specificity. To cluster the dynamically coupled residues in GEF-GTPase complexes a novel intra-residue backbone-torsion-angles based mutual information (TMI) technique was employed. TMI was calculated from 4500 trajectories obtained from a total of 4.5μs molecular dynamics simulations performed on members of all the three clades of DOCK GEFs. The obtained clusters suggest a specificity generation mechanism that involves optimization of the binding pocket for the crucial divergent residue at the 56th position of Rac/Cdc42 (FCdc42/WRac1). These clusters encompass five residues from the structural segment lobe C - α10 helix of the DOCK proteins and functional SWI region of GTPase, which induce orchestrated structural modulations to generate the specificity. Even the conserved residues from SWI region are seen to augment the specificity defining dynamical rearrangements. Furthermore, the proposed dynamical GTPase- DOCK GEF specificity model was verified using mutagenesis studies on Rac1 and dual GTPase specific Dock2 and Dock6, respectively. Thus the current study provides the generic substrate specificity determinants of DOCK GEFs, which are not apparent from the conventional structural analysis.
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Affiliation(s)
- Debopriya Roy
- Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, 411008, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Durba Sengupta
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune, 411008, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Kiran Kulkarni
- Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, 411008, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
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8
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Del Gaudio I, Camerer E. Distinct GEFs Couple S1PR1 to Rac for Endothelial Barrier Enhancement and Lymphocyte Trafficking. Arterioscler Thromb Vasc Biol 2022; 42:903-905. [PMID: 35616033 DOI: 10.1161/atvbaha.122.317794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Ilaria Del Gaudio
- From the Université Paris Cité, Inserm, PARCC, F-75015 Paris, France
| | - Eric Camerer
- From the Université Paris Cité, Inserm, PARCC, F-75015 Paris, France
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9
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Mallery EL, Yanagisawa M, Zhang C, Lee Y, Robles LM, Alonso JM, Szymanski DB. Tandem C2 domains mediate dynamic organelle targeting of a DOCK family guanine nucleotide exchange factor. J Cell Sci 2022; 135:275003. [PMID: 35194638 DOI: 10.1242/jcs.259825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 02/11/2022] [Indexed: 11/20/2022] Open
Abstract
Multicellular organisms use DOCK family guanine nucleotide exchange factors to activate Rac/Rho-of-Plants small GTPases and coordinate cell shape change. In developing tissues, DOCK signals integrate cell-cell interactions with cytoskeleton remodeling, and the GEFs cluster reversibly at specific organelle surfaces to orchestrate cytoskeletal reorganization. The domain organizations among DOCK orthologs are diverse, and the mechanisms of localization control are poorly understood. Here we use combinations of transgene complementation and live cell imaging assays to uncover an evolutionarily conserved and essential localization determinant in the DOCK-GEF named SPIKE1. The SPIKE1-DHR3 domain is sufficient for organelle association in vivo, and displays a complicated lipid binding selectivity for both phospholipid head groups and fatty acid chain saturation. SPIKE1-DHR3 is predicted to adopt a C2-domain structure and functions as part of tandem C2 array that enables reversible clustering at the cell apex. This work provides mechanistic insight into how DOCK GEFs sense compositional and biophysical membrane properties at the interface of two organelle systems.
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Affiliation(s)
- Eileen L Mallery
- Departments of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Makoto Yanagisawa
- Departments of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Chunhua Zhang
- Departments of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA.,Center for Plant Biology, Purdue University, West Lafayette, IN, 47907, USA
| | - Youngwoo Lee
- Departments of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA.,Center for Plant Biology, Purdue University, West Lafayette, IN, 47907, USA
| | - Linda M Robles
- Department of Plant & Microbial Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Jose M Alonso
- Department of Plant & Microbial Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Daniel B Szymanski
- Departments of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA.,Center for Plant Biology, Purdue University, West Lafayette, IN, 47907, USA.,Department of Biological Sciences, Purdue University, West Lafayette, IN, 47907, USA
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10
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Comer SP. Turning Platelets Off and On: Role of RhoGAPs and RhoGEFs in Platelet Activity. Front Cardiovasc Med 2022; 8:820945. [PMID: 35071371 PMCID: PMC8770426 DOI: 10.3389/fcvm.2021.820945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 12/15/2021] [Indexed: 12/15/2022] Open
Abstract
Platelet cytoskeletal reorganisation is a critical component of platelet activation and thrombus formation in haemostasis. The Rho GTPases RhoA, Rac1 and Cdc42 are the primary drivers in the dynamic reorganisation process, leading to the development of filopodia and lamellipodia which dramatically increase platelet surface area upon activation. Rho GTPases cycle between their active (GTP-bound) and inactive (GDP-bound) states through tightly regulated processes, central to which are the guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). GEFs catalyse the dissociation of GDP by inducing changes in the nucleotide binding site, facilitating GTP binding and activating Rho GTPases. By contrast, while all GTPases possess intrinsic hydrolysing activity, this reaction is extremely slow. Therefore, GAPs catalyse the hydrolysis of GTP to GDP, reverting Rho GTPases to their inactive state. Our current knowledge of these proteins is constantly being updated but there is considerably less known about the functionality of Rho GTPase specific GAPs and GEFs in platelets. In the present review, we discuss GAP and GEF proteins for Rho GTPases identified in platelets, their regulation, biological function and present a case for their further study in platelets.
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Affiliation(s)
- Shane P Comer
- ConwaySPHERE Research Group, UCD Conway Institute, University College Dublin, Dublin, Ireland.,School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
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11
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Hurst M, McGarry DJ, Olson MF. Rho GTPases: Non-canonical regulation by cysteine oxidation. Bioessays 2021; 44:e2100152. [PMID: 34889471 DOI: 10.1002/bies.202100152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 11/18/2021] [Accepted: 11/19/2021] [Indexed: 12/20/2022]
Abstract
Rho GTPases are critically important and are centrally positioned regulators of the actomyosin cytoskeleton. By influencing the organization and architecture of the cytoskeleton, Rho proteins play prominent roles in many cellular processes including adhesion, migration, intra-cellular transportation, and proliferation. The most important method of Rho GTPase regulation is via the GTPase cycle; however, post-translational modifications (PTMs) also play critical roles in Rho protein regulation. Relative to other PTMs such as lipidation or phosphorylation that have been extensively characterized, protein oxidation is a regulatory PTM that has been poorly studied. Protein oxidation primarily occurs from the reaction of reactive oxygen species (ROS), such as hydrogen peroxide (H2 O2 ), with amino acid side chain thiols on cysteine (Cys) and methionine (Met) residues. The versatile redox modifications of cysteine residues exemplify their integral role in cell signalling processes. Here we review prominent members of the Rho GTPase family and discuss how lipidation, phosphorylation, and oxidation on conserved cysteine residues affects their regulation and function.
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Affiliation(s)
- Mackenzie Hurst
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - David J McGarry
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Michael F Olson
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
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12
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Kukimoto-Niino M, Ihara K, Murayama K, Shirouzu M. Structural insights into the small GTPase specificity of the DOCK guanine nucleotide exchange factors. Curr Opin Struct Biol 2021; 71:249-258. [PMID: 34507037 DOI: 10.1016/j.sbi.2021.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/02/2021] [Accepted: 08/06/2021] [Indexed: 10/20/2022]
Abstract
The dedicator of cytokinesis (DOCK) family of guanine nucleotide exchange factors (GEFs) regulates cytoskeletal dynamics by activating the GTPases Rac and/or Cdc42. Eleven human DOCK proteins play various important roles in developmental processes and the immune system. Of these, DOCK1-5 proteins bind to engulfment and cell motility (ELMO) proteins to perform their physiological functions. Recent structural studies have greatly enhanced our understanding of the complex and diverse mechanisms of DOCK GEF activity and GTPase recognition and its regulation by ELMO. This review is focused on gaining structural insights into the substrate specificity of the DOCK GEFs, and discuss how Rac and Cdc42 are specifically recognized by the catalytic DHR-2 and surrounding domains of DOCK or binding partners.
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Affiliation(s)
- Mutsuko Kukimoto-Niino
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Kentaro Ihara
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Kazutaka Murayama
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan; Graduate School of Biomedical Engineering, Tohoku University, 2-1 Seiryo, Aoba-ku, Sendai, Miyagi 980-8575, Japan
| | - Mikako Shirouzu
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan.
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