RhoD regulates cytoskeletal dynamics via the actin nucleation–promoting factor WASp homologue associated with actin Golgi membranes and microtubules

The Rho GTPases have mainly been studied in association with their roles in the regulation of actin filament organization. These studies have shown that the Rho GTPases are essential for basic cellular processes, such as cell migration, contraction, and division. In this paper, we report that RhoD has a role in the organization of actin dynamics that is distinct from the roles of the better-studied Rho members Cdc42, RhoA, and Rac1. We found that RhoD binds the actin nucleation–promoting factor WASp homologue associated with actin Golgi membranes and microtubules (WHAMM), as well as the related filamin A–binding protein FILIP1. Of these two RhoD-binding proteins, WHAMM was found to bind to the Arp2/3 complex, while FILIP1 bound filamin A. WHAMM was found to act downstream of RhoD in regulating cytoskeletal dynamics. In addition, cells treated with small interfering RNAs for RhoD and WHAMM showed increased cell attachment and decreased cell migration. These major effects on cytoskeletal dynamics indicate that RhoD and its effectors control vital cytoskeleton-driven cellular processes. In agreement with this notion, our data suggest that RhoD coordinates Arp2/3-dependent and FLNa-dependent mechanisms to control the actin filament system, cell adhesion, and cell migration.

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Atypical Rho GTPases RhoD and Rif integrate cytoskeletal dynamics and membrane trafficking

Biological Chemistry ◽

10.1515/hsz-2013-0296 ◽

2014 ◽

Vol 395 (5) ◽

pp. 477-484 ◽

Cited By ~ 8

Author(s):

Pontus Aspenström

Keyword(s):

Cell Migration ◽

Cell Division ◽

Membrane Trafficking ◽

Rho Gtpases ◽

Intracellular Transport ◽

Cell Contraction ◽

Cell Behaviour ◽

Master Regulators ◽

Cellular Processes ◽

Cytoskeletal Dynamics

Abstract The Rho GTPases are essential regulators of basic cellular processes, including cell migration, cell contraction and cell division. Most studies still involve just the three canonical members, RhoA, Rac1 and Cdc42, although the Rho GTPases comprise at least 20 members. The aim of this review is to highlight some of the recent advances in our knowledge regarding the less-studied Rho members, with the focus on RhoD and Rif. The phenotypic alterations to cell behaviour that are triggered by RhoD and Rif suggest that they have unique impacts on cytoskeletal dynamics that distinguish them from the well-studied members of the Rho GTPases. In addition, RhoD has a role in the regulation of intracellular transport of vesicles. Taken together, the available data indicate that RhoD and Rif have functions as master regulators in the integration of cytoskeletal reorganisation and membrane trafficking.

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Actin dynamics in cell migration

Essays in Biochemistry ◽

10.1042/ebc20190015 ◽

2019 ◽

Vol 63 (5) ◽

pp. 483-495 ◽

Cited By ~ 22

Author(s):

Matthias Schaks ◽

Grégory Giannone ◽

Klemens Rottner

Keyword(s):

Plasma Membrane ◽

Cell Migration ◽

Actin Filament ◽

Rho Gtpases ◽

Rho Gtpase ◽

Actin Dynamics ◽

Regulatory Complex ◽

Membrane Protrusions ◽

Filament Networks ◽

Contractile Forces

Abstract Cell migration is an essential process, both in unicellular organisms such as amoeba and as individual or collective motility in highly developed multicellular organisms like mammals. It is controlled by a variety of activities combining protrusive and contractile forces, normally generated by actin filaments. Here, we summarize actin filament assembly and turnover processes, and how respective biochemical activities translate into different protrusion types engaged in migration. These actin-based plasma membrane protrusions include actin-related protein 2/3 complex-dependent structures such as lamellipodia and membrane ruffles, filopodia as well as plasma membrane blebs. We also address observed antagonisms between these protrusion types, and propose a model – also inspired by previous literature – in which a complex balance between specific Rho GTPase signaling pathways dictates the protrusion mechanism employed by cells. Furthermore, we revisit published work regarding the fascinating antagonism between Rac and Rho GTPases, and how this intricate signaling network can define cell behavior and modes of migration. Finally, we discuss how the assembly of actin filament networks can feed back onto their regulators, as exemplified for the lamellipodial factor WAVE regulatory complex, tightly controlling accumulation of this complex at specific subcellular locations as well as its turnover.

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The Intrinsic GDP/GTP Exchange Activities of Cdc42 and Rac1 Are Critical Determinants for Their Specific Effects on Mobilization of the Actin Filament System

Cells ◽

10.3390/cells8070759 ◽

2019 ◽

Vol 8 (7) ◽

pp. 759 ◽

Cited By ~ 7

Author(s):

Pontus Aspenström

Keyword(s):

Actin Filament ◽

Rho Gtpases ◽

Focal Adhesions ◽

Small Gtpases ◽

Migration And Invasion ◽

Actin Nucleation ◽

Filament System ◽

Prevailing Paradigm ◽

Specific Effects ◽

Cytoskeletal Dynamics

The Rho GTPases comprise a subfamily of the Ras superfamily of small GTPases. Their importance in regulation of cell morphology and cell migration is well characterized. According to the prevailing paradigm, Cdc42 regulates the formation of filopodia, Rac1 regulates the formation of lamellipodia, and RhoA triggers the assembly of focal adhesions. However, this scheme is clearly an oversimplification, as the Rho subfamily encompasses 20 members with diverse effects on a number of vital cellular processes, including cytoskeletal dynamics and cell proliferation, migration, and invasion. This article highlights the importance of the catalytic activities of the classical Rho GTPases Cdc42 and Rac1, in terms of their specific effects on the dynamic reorganization of the actin filament system. GTPase-deficient mutants of Cdc42 and Rac1 trigger the formation of broad lamellipodia and stress fibers, and fast-cycling mutations trigger filopodia formation and stress fiber dissolution. The filopodia response requires the involvement of the formin family of actin nucleation promotors. In contrast, the formation of broad lamellipodia induced by GTPase-deficient Cdc42 and Rac1 is mediated through Arp2/3-dependent actin nucleation.

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Regulation of Rho GTPases by RhoGDIs in Human Cancers

Cells ◽

10.3390/cells8091037 ◽

2019 ◽

Vol 8 (9) ◽

pp. 1037 ◽

Cited By ~ 6

Author(s):

Cho ◽

Kim ◽

Baek ◽

Kim ◽

Lee

Keyword(s):

Cell Migration ◽

Cancer Progression ◽

Anticancer Agents ◽

Rho Gtpases ◽

Rho Gtpase ◽

Regulatory Mechanisms ◽

Malignant Phenotype ◽

Cellular Processes ◽

Human Cancers

Rho GDP dissociation inhibitors (RhoGDIs) play important roles in various cellular processes, including cell migration, adhesion, and proliferation, by regulating the functions of the Rho GTPase family. Dissociation of Rho GTPases from RhoGDIs is necessary for their spatiotemporal activation and is dynamically regulated by several mechanisms, such as phosphorylation, sumoylation, and protein interaction. The expression of RhoGDIs has changed in many human cancers and become associated with the malignant phenotype, including migration, invasion, metastasis, and resistance to anticancer agents. Here, we review how RhoGDIs control the function of Rho GTPases by regulating their spatiotemporal activity and describe the regulatory mechanisms of the dissociation of Rho GTPases from RhoGDIs. We also discuss the role of RhoGDIs in cancer progression and their potential uses for therapeutic intervention.

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Regulation of Rho GTPases in the Vasculature by Cullin3-Based E3 Ligase Complexes

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.680901 ◽

2021 ◽

Vol 9 ◽

Author(s):

Fabienne Podieh ◽

Peter L. Hordijk

Keyword(s):

Rho Gtpases ◽

Vascular Function ◽

Rho Gtpase ◽

Current Knowledge ◽

E3 Ligase ◽

Small Gtpases ◽

E3 Ligases ◽

Cellular Processes ◽

Ubiquitin E3 Ligase ◽

Cytoskeletal Dynamics

Cullin3-based ubiquitin E3 ligases induce ubiquitination of substrates leading to their proteasomal or lysosomal degradation. BTB proteins serve as adaptors by binding to Cullin3 and recruiting substrate proteins, which enables specific recognition of a broad spectrum of targets. Hence, Cullin3 and its adaptors are involved in myriad cellular processes and organ functions. Cullin3-based ubiquitin E3 ligase complexes target small GTPases of the Rho subfamily, which are key regulators of cytoskeletal dynamics and cell adhesion. In this mini review, we discuss recent insights in Cullin3-mediated regulation of Rho GTPases and their impact on cellular function and disease. Intriguingly, upstream regulators of Rho GTPases are targeted by Cullin3 complexes as well. Thus, Rho GTPase signaling is regulated by Cullin3 on multiple levels. In addition, we address current knowledge of Cullin3 in regulating vascular function, focusing on its prominent role in endothelial barrier function, angiogenesis and the regulation of blood pressure.

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Actin-depolymerizing Factor and Cofilin-1 Play Overlapping Roles in Promoting Rapid F-Actin Depolymerization in Mammalian Nonmuscle Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e04-07-0555 ◽

2005 ◽

Vol 16 (2) ◽

pp. 649-664 ◽

Cited By ~ 240

Author(s):

Pirta Hotulainen ◽

Eija Paunola ◽

Maria K. Vartiainen ◽

Pekka Lappalainen

Keyword(s):

Cell Motility ◽

Actin Filament ◽

Actin Filaments ◽

Actin Dynamics ◽

Actin Binding ◽

Actin Depolymerizing Factor ◽

Cytoskeletal Dynamics ◽

Nonmuscle Cells ◽

In Cells

Actin-depolymerizing factor (ADF)/cofilins are small actin-binding proteins found in all eukaryotes. In vitro, ADF/cofilins promote actin dynamics by depolymerizing and severing actin filaments. However, whether ADF/cofilins contribute to actin dynamics in cells by disassembling “old” actin filaments or by promoting actin filament assembly through their severing activity is a matter of controversy. Analysis of mammalian ADF/cofilins is further complicated by the presence of multiple isoforms, which may contribute to actin dynamics by different mechanisms. We show that two isoforms, ADF and cofilin-1, are expressed in mouse NIH 3T3, B16F1, and Neuro 2A cells. Depleting cofilin-1 and/or ADF by siRNA leads to an accumulation of F-actin and to an increase in cell size. Cofilin-1 and ADF seem to play overlapping roles in cells, because the knockdown phenotype of either protein could be rescued by overexpression of the other one. Cofilin-1 and ADF knockdown cells also had defects in cell motility and cytokinesis, and these defects were most pronounced when both ADF and cofilin-1 were depleted. Fluorescence recovery after photobleaching analysis and studies with an actin monomer-sequestering drug, latrunculin-A, demonstrated that these phenotypes arose from diminished actin filament depolymerization rates. These data suggest that mammalian ADF and cofilin-1 promote cytoskeletal dynamics by depolymerizing actin filaments and that this activity is critical for several processes such as cytokinesis and cell motility.

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Aqueous Extract ofPaeonia suffruticosaInhibits Migration and Metastasis of Renal Cell Carcinoma Cells via Suppressing VEGFR-3 Pathway

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2012/409823 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Shih-Chin Wang ◽

Sai-Wen Tang ◽

Sio-Hong Lam ◽

Chung-Chieh Wang ◽

Yu-Huei Liu ◽

...

Keyword(s):

Renal Cell Carcinoma ◽

Cell Migration ◽

Cell Carcinoma ◽

Aqueous Extract ◽

Actin Filament ◽

Renal Cell ◽

Chinese Herbs ◽

Vegf Receptor ◽

Cytoskeletal Dynamics ◽

Cell Migration And Proliferation

Renal cell carcinoma (RCC) cells are characterized by strong drug resistance and high metastatic incidence. In this study, the effects of ten kinds of Chinese herbs on RCC cell migration and proliferation were examined. Aqueous extract ofPaeonia suffruticosa(PS-A) exerted strong inhibitory effects on cancer cell migration, mobility, and invasion. The results of mouse xenograft experiments showed that the treatment of PS-A significantly suppressed tumor growth and pulmonary metastasis. We further found that PS-A markedly decreased expression of VEGF receptor-3 (VEGFR-3) and phosphorylation of FAK in RCC cells. Moreover, the activation of Rac-1, a modulator of cytoskeletal dynamics, was remarkably reduced by PS-A. Additionally, PS-A suppressed polymerization of actin filament as demonstrated by confocal microscopy analysis and decreased the ratio of F-actin to G-actin in RCC cells, suggesting that PS-A inhibits RCC cell migration through modulating VEGFR-3/FAK/Rac-1 pathway to disrupt actin filament polymerization. In conclusion, this research elucidates the effects and molecular mechanism for antimigration of PS-A on RCC cells and suggests PS-A to be a therapeutic or adjuvant strategy for the patients with aggressive RCC.

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Rho GTPases and their effector proteins

Biochemical Journal ◽

10.1042/bj3480241 ◽

2000 ◽

Vol 348 (2) ◽

pp. 241-255 ◽

Cited By ~ 824

Author(s):

Anne L. BISHOP ◽

Alan HALL

Keyword(s):

Rho Gtpases ◽

Cell Cycle Progression ◽

Biological Effects ◽

Effector Proteins ◽

Actin Dynamics ◽

Filamentous Actin ◽

Cycle Progression ◽

Cellular Processes ◽

Specific Effector ◽

Rho Family

Rho GTPases are molecular switches that regulate many essential cellular processes, including actin dynamics, gene transcription, cell-cycle progression and cell adhesion. About 30 potential effector proteins have been identified that interact with members of the Rho family, but it is still unclear which of these are responsible for the diverse biological effects of Rho GTPases. This review will discuss how Rho GTPases physically interact with, and regulate the activity of, multiple effector proteins and how specific effector proteins contribute to cellular responses. To date most progress has been made in the cytoskeleton field, and several biochemical links have now been established between GTPases and the assembly of filamentous actin. The main focus of this review will be Rho, Rac and Cdc42, the three best characterized mammalian Rho GTPases, though the genetic analysis of Rho GTPases in lower eukaryotes is making increasingly important contributions to this field.

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Roles of Rho GTPases in leucocyte and leukaemia cell transendothelial migration

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2013.0013 ◽

2013 ◽

Vol 368 (1629) ◽

pp. 20130013 ◽

Cited By ~ 14

Author(s):

Elvira Infante ◽

Anne J. Ridley

Keyword(s):

Cell Migration ◽

Blood Vessels ◽

Rho Gtpases ◽

Rho Gtpase ◽

Immune Surveillance ◽

Transendothelial Migration ◽

Cell Entry ◽

Leukaemia Cell ◽

Multiple Points ◽

Cytoskeletal Dynamics

Leucocytes migrate into and out of blood vessels at multiple points during their development and maturation, and during immune surveillance. In response to tissue damage and infection, they are rapidly recruited through the endothelium lining blood vessels into the tissues. Leukaemia cells also move in and out of the bloodstream during leukaemia progression. Rho GTPases are intracellular signalling proteins that regulate cytoskeletal dynamics and are key coordinators of cell migration. Here, we describe how different members of the Rho GTPase family act in leucocytes and leukaemia cells to regulate steps of transendothelial migration. We discuss how inhibitors of Rho signalling could be used to reduce leucocyte or leukaemia cell entry into tissues.

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Enhancement of Actin-depolymerizing Factor/Cofilin-dependent Actin Disassembly by Actin-interacting Protein 1 Is Required for Organized Actin Filament Assembly in the Caenorhabditis elegans Body Wall Muscle

Molecular Biology of the Cell ◽

10.1091/mbc.e05-11-1016 ◽

2006 ◽

Vol 17 (5) ◽

pp. 2190-2199 ◽

Cited By ~ 33

Author(s):

Kurato Mohri ◽

Kanako Ono ◽

Robinson Yu ◽

Sawako Yamashiro ◽

Shoichiro Ono

Keyword(s):

Actin Filament ◽

Actin Filaments ◽

Muscle Cells ◽

Actin Depolymerizing Factor ◽

Interacting Protein ◽

Cellular Processes ◽

Cytoskeletal Dynamics ◽

End Capping

Regulated disassembly of actin filaments is involved in several cellular processes that require dynamic rearrangement of the actin cytoskeleton. Actin-interacting protein (AIP) 1 specifically enhances disassembly of actin-depolymerizing factor (ADF)/cofilin-bound actin filaments. In vitro, AIP1 actively disassembles filaments, caps barbed ends, and binds to the side of filaments. However, how AIP1 functions in the cellular actin cytoskeletal dynamics is not understood. We compared biochemical and in vivo activities of mutant UNC-78 proteins and found that impaired activity of mutant UNC-78 proteins to enhance disassembly of ADF/cofilin-bound actin filaments is associated with inability to regulate striated organization of actin filaments in muscle cells. Six functionally important residues are present in the N-terminal β-propeller, whereas one residue is located in the C-terminal β-propeller, suggesting the presence of two separate sites for interaction with ADF/cofilin and actin. In vitro, these mutant UNC-78 proteins exhibited variable alterations in actin disassembly and/or barbed end-capping activities, suggesting that both activities are important for its in vivo function. These results indicate that the actin-regulating activity of AIP1 in cooperation with ADF/cofilin is essential for its in vivo function to regulate actin filament organization in muscle cells.

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