Abi2-Deficient Mice Exhibit Defective Cell Migration, Aberrant Dendritic Spine Morphogenesis, and Deficits in Learning and Memory

ABSTRACT The Abl-interactor (Abi) family of adaptor proteins has been linked to signaling pathways involving the Abl tyrosine kinases and the Rac GTPase. Abi proteins localize to sites of actin polymerization in protrusive membrane structures and regulate actin dynamics in vitro. Here we demonstrate that Abi2 modulates cell morphogenesis and migration in vivo. Homozygous deletion of murine abi2 produced abnormal phenotypes in the eye and brain, the tissues with the highest Abi2 expression. In the absence of Abi2, secondary lens fiber orientation and migration were defective in the eye, without detectable defects in proliferation, differentiation, or apoptosis. These phenotypes were consistent with the localization of Abi2 at adherens junctions in the developing lens and at nascent epithelial cell adherens junctions in vitro. Downregulation of Abi expression by RNA interference impaired adherens junction formation and correlated with downregulation of the Wave actin-nucleation promoting factor. Loss of Abi2 also resulted in cell migration defects in the neocortex and hippocampus, abnormal dendritic spine morphology and density, and severe deficits in short- and long-term memory. These findings support a role for Abi2 in the regulation of cytoskeletal dynamics at adherens junctions and dendritic spines, which is critical for intercellular connectivity, cell morphogenesis, and cognitive functions.

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The roles and prognostic significance of ABI1-TSV-11 expression in patients with left-sided colorectal cancer

Scientific Reports ◽

10.1038/s41598-021-90220-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yu Zhang ◽

Zhaohui Zhong ◽

Mei Li ◽

Jingyi Chen ◽

Tingru Lin ◽

...

Keyword(s):

Colorectal Cancer ◽

Prognostic Significance ◽

Growth Factor Receptor ◽

The Cancer Genome Atlas ◽

Actin Dynamics ◽

Elevated Expression ◽

Sw480 Cells ◽

And Migration

AbstractAbnormally expressed and/or phosphorylated Abelson interactor 1 (ABI1) participates in the metastasis and progression of colorectal cancer (CRC). ABI1 presents as at least 12 transcript variants (TSVs) by mRNA alternative splicing, but it is unknown which of them is involved in CRC metastasis and prognosis. Here, we firstly identified ABI1-TSV-11 as a key TSV affecting the metastasis and prognosis of left-sided colorectal cancer (LsCC) and its elevated expression is related to lymph node metastasis and shorter overall survival (OS) in LsCC by analyzing data from The Cancer Genome Atlas and TSVdb. Secondly, ABI1-TSV-11 overexpression promoted LoVo and SW480 cells adhesion and migration in vitro, and accelerated LoVo and SW480 cells lung metastasis in vivo. Finally, mechanism investigations revealed that ABI1-isoform-11 interacted with epidermal growth factor receptor pathway substrate 8 (ESP8) and regulated actin dynamics to affect LoVo and SW480 cells biological behaviors. Taken together, our data demonstrated that ABI1-TSV-11 plays an oncogenic role in LsCC, it is an independent risk factor of prognosis and may be a potential molecular marker and therapeutic target in LsCC.

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WDR5 modulates cell motility and morphology and controls nuclear changes induced by a 3D environment

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1719405115 ◽

2018 ◽

Vol 115 (34) ◽

pp. 8581-8586 ◽

Cited By ~ 22

Author(s):

Pengbo Wang ◽

Marcel Dreger ◽

Elena Madrazo ◽

Craig J. Williams ◽

Rafael Samaniego ◽

...

Keyword(s):

Cell Migration ◽

Cell Polarity ◽

Underlying Mechanism ◽

H3k4 Methylation ◽

Nuclear Mechanics ◽

3D Environment ◽

3D Environments ◽

And Migration

Cell migration through extracellular matrices requires nuclear deformation, which depends on nuclear stiffness. In turn, chromatin structure contributes to nuclear stiffness, but the mechanosensing pathways regulating chromatin during cell migration remain unclear. Here, we demonstrate that WD repeat domain 5 (WDR5), an essential component of H3K4 methyltransferase complexes, regulates cell polarity, nuclear deformability, and migration of lymphocytes in vitro and in vivo, independent of transcriptional activity, suggesting nongenomic functions for WDR5. Similarly, depletion of RbBP5 (another H3K4 methyltransferase subunit) promotes similar defects. We reveal that a 3D environment increases the H3K4 methylation dependent on WDR5 and results in a globally less compacted chromatin conformation. Further, using atomic force microscopy, nuclear particle tracking, and nuclear swelling experiments, we detect changes in nuclear mechanics that accompany the epigenetic changes induced in 3D conditions. Indeed, nuclei from cells in 3D environments were softer, and thereby more deformable, compared with cells in suspension or cultured in 2D conditions, again dependent on WDR5. Dissecting the underlying mechanism, we determined that actomyosin contractility, through the phosphorylation of myosin by MLCK (myosin light chain kinase), controls the interaction of WDR5 with other components of the methyltransferase complex, which in turn up-regulates H3K4 methylation activation in 3D conditions. Taken together, our findings reveal a nongenomic function for WDR5 in regulating H3K4 methylation induced by 3D environments, physical properties of the nucleus, cell polarity, and cell migratory capacity.

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Small-Molecule Screen Identifies ROS as Key Regulators of Actin Dynamics in Neutrophils

Blood ◽

10.1182/blood.v112.11.4641.4641 ◽

2008 ◽

Vol 112 (11) ◽

pp. 4641-4641

Author(s):

Hidenori Hattori ◽

Kulandayan K Subramanian ◽

Hongbo R. Luo

Keyword(s):

Small Molecule ◽

Actin Polymerization ◽

Neutrophil Migration ◽

Physiological Role ◽

Leading Edge ◽

Actin Dynamics ◽

Functional Screening ◽

Cellular Processes

Abstract Precise spatial and temporal control of actin polymerization and depolymerization is essential for mediating various cellular processes such as migration, phagocytosis, vesicle trafficking and adhesion. In this study, we used a small-molecule functional screening approach to identify novel regulators of actin dynamics during neutrophil migration. Here we show that NADPH-oxidase dependent Reactive Oxygen Species act as negative regulators of actin polymerization. Neutrophils with pharmacologically inhibited oxidase or isolated from Chronic Granulomatous Disease (CGD) patient and mice displayed enhanced F-actin polymerization, multiple pseudopods formation and impaired chemotaxis. ROS localized to pseudopodia and inhibited actin polymerization by driving actin glutathionylation at the leading edge of migrating cells. Consistent with these in vitro results, adoptively transferred CGD murine neutrophils also showed impaired in vivo recruitment to sites of inflammation. Together, these results present a novel physiological role for ROS in regulation of action polymerization and shed new light on the pathogenesis of CGD.

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Mammalian Adenylyl Cyclase-associated Protein 1 (CAP1) Regulates Cofilin Function, the Actin Cytoskeleton, and Cell Adhesion

Journal of Biological Chemistry ◽

10.1074/jbc.m113.484535 ◽

2013 ◽

Vol 288 (29) ◽

pp. 20966-20977 ◽

Cited By ~ 51

Author(s):

Haitao Zhang ◽

Pooja Ghai ◽

Huhehasi Wu ◽

Changhui Wang ◽

Jeffrey Field ◽

...

Keyword(s):

Cell Adhesion ◽

Actin Cytoskeleton ◽

Hela Cells ◽

Actin Polymerization ◽

Actin Dynamics ◽

Ras Signaling ◽

Filamentous Actin ◽

Camp Pathway

CAP (adenylyl cyclase-associated protein) was first identified in yeast as a protein that regulates both the actin cytoskeleton and the Ras/cAMP pathway. Although the role in Ras signaling does not extend beyond yeast, evidence supports that CAP regulates the actin cytoskeleton in all eukaryotes including mammals. In vitro actin polymerization assays show that both mammalian and yeast CAP homologues facilitate cofilin-driven actin filament turnover. We generated HeLa cells with stable CAP1 knockdown using RNA interference. Depletion of CAP1 led to larger cell size and remarkably developed lamellipodia as well as accumulation of filamentous actin (F-actin). Moreover, we found that CAP1 depletion also led to changes in cofilin phosphorylation and localization as well as activation of focal adhesion kinase (FAK) and enhanced cell spreading. CAP1 forms complexes with the adhesion molecules FAK and Talin, which likely underlie the cell adhesion phenotypes through inside-out activation of integrin signaling. CAP1-depleted HeLa cells also had substantially elevated cell motility as well as invasion through Matrigel. In summary, in addition to generating in vitro and in vivo evidence further establishing the role of mammalian CAP1 in actin dynamics, we identified a novel cellular function for CAP1 in regulating cell adhesion.

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N-WASP inhibitor wiskostatin nonselectively perturbs membrane transport by decreasing cellular ATP levels

AJP Cell Physiology ◽

10.1152/ajpcell.00426.2006 ◽

2007 ◽

Vol 292 (4) ◽

pp. C1562-C1566 ◽

Cited By ~ 32

Author(s):

Christopher J. Guerriero ◽

Ora A. Weisz

Keyword(s):

Membrane Trafficking ◽

Actin Polymerization ◽

Cell Function ◽

Actin Dynamics ◽

Cellular Functions ◽

Intact Cells ◽

Atp Levels ◽

Dependent Inhibition

Wiskott-Aldrich syndrome protein (WASP) and WAVE stimulate actin-related protein (Arp)2/3-mediated actin polymerization, leading to diverse downstream effects, including the formation and remodeling of cell surface protrusions, modulation of cell migration, and intracytoplasmic propulsion of organelles and pathogens. Selective inhibitors of individual Arp2/3 activators would enable more exact dissection of WASP- and WAVE-dependent cellular pathways and are potential therapeutic targets for viral pathogenesis. Wiskostatin is a recently described chemical inhibitor that selectively inhibits neuronal WASP (N-WASP)-mediated actin polymerization in vitro. A growing number of recent studies have utilized this drug in vivo to uncover novel cellular functions for N-WASP; however, the selectivity of wiskostatin in intact cells has not been carefully explored. In our studies with this drug, we observed rapid and dose-dependent inhibition of N-WASP-dependent membrane trafficking steps. Additionally, however, we found that addition of wiskostatin inhibited numerous other cellular functions that are not believed to be N-WASP dependent. Further studies revealed that wiskostatin treatment caused a rapid, profound, and irreversible decrease in cellular ATP levels, consistent with its global effects on cell function. Our data caution against the use of this drug as a selective perturbant of N-WASP-dependent actin dynamics in vivo.

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Disease-associated missense mutations in the EVH1 domain disrupt intrinsic WASp function causing dysregulated actin dynamics and impaired dendritic cell migration

Blood ◽

10.1182/blood-2012-01-403857 ◽

2013 ◽

Vol 121 (1) ◽

pp. 72-84 ◽

Cited By ~ 11

Author(s):

Austen J. J. Worth ◽

Joao Metelo ◽

Gerben Bouma ◽

Dale Moulding ◽

Marco Fritzsche ◽

...

Keyword(s):

Actin Polymerization ◽

Actin Dynamics ◽

Missense Mutations ◽

Loss Of Function ◽

Interacting Protein ◽

Mutant Proteins ◽

Dendritic Cell Migration ◽

Biologic Function

Abstract Wiskott Aldrich syndrome (WAS), an X-linked immunodeficiency, results from loss-of-function mutations in the human hematopoietic cytoskeletal regulator gene WAS. Many missense mutations in the Ena Vasp homology1 (EVH1) domain preserve low-level WAS protein (WASp) expression and confer a milder clinical phenotype. Although disrupted binding to WASp-interacting protein (WIP) leads to enhanced WASp degradation in vivo, the intrinsic function of EVH1-mutated WASp is poorly understood. In the present study, we show that, despite mediating enhanced actin polymerization compared with wild-type WASp in vitro, EVH1 missense mutated proteins did not support full biologic function in cells, even when levels were restored by forced overexpression. Podosome assembly was aberrant and associated with dysregulated lamellipodia formation and impaired persistence of migration. At sites of residual podosome-associated actin polymerization, localization of EVH1-mutated proteins was preserved even after deletion of the entire domain, implying that WIP-WASp complex formation is not absolutely required for WASp localization. However, retention of mutant proteins in podosomes was significantly impaired and associated with reduced levels of WASp tyrosine phosphorylation. Our results indicate that the EVH1 domain is important not only for WASp stability, but also for intrinsic biologic activity in vivo.

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Distinct phospho-forms of cortactin differentially regulate actin polymerization and focal adhesions

AJP Cell Physiology ◽

10.1152/ajpcell.00238.2008 ◽

2008 ◽

Vol 295 (5) ◽

pp. C1113-C1122 ◽

Cited By ~ 37

Author(s):

Anne E. Kruchten ◽

Eugene W. Krueger ◽

Yu Wang ◽

Mark A. McNiven

Keyword(s):

Cell Migration ◽

Focal Adhesion ◽

Actin Polymerization ◽

Control Cell ◽

Focal Adhesions ◽

Serine Phosphorylation ◽

Actin Binding ◽

Actin Assembly

Cortactin is an actin-binding protein that is overexpressed in many cancers and is a substrate for both tyrosine and serine/threonine kinases. Tyrosine phosphorylation of cortactin has been observed to increase cell motility and invasion in vivo, although it has been reported to have both positive and negative effects on actin polymerization in vitro. In contrast, serine phosphorylation of cortactin has been shown to stimulate actin assembly in vitro. Currently, the effects of cortactin serine phosphorylation on cell migration are unclear, and furthermore, how the distinct phospho-forms of cortactin may differentially contribute to cell migration has not been directly compared. Therefore, we tested the effects of different tyrosine and serine phospho-mutants of cortactin on lamellipodial protrusion, actin assembly within cells, and focal adhesion dynamics. Interestingly, while expression of either tyrosine or serine phospho-mimetic cortactin mutants resulted in increased lamellipodial protrusion and cell migration, these effects appeared to be via distinct processes. Cortactin mutants mimicking serine phosphorylation appeared to predominantly affect actin polymerization, whereas mutation of cortactin tyrosine residues resulted in alterations in focal adhesion turnover. Thus these findings provide novel insights into how distinct phospho-forms of cortactin may differentially contribute to actin and focal adhesion dynamics to control cell migration.

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Actin Dynamics Is Controlled by a Casein Kinase II and Phosphatase 2C Interplay on Toxoplasma gondii Toxofilin

Molecular Biology of the Cell ◽

10.1091/mbc.e02-08-0462 ◽

2003 ◽

Vol 14 (5) ◽

pp. 1900-1912 ◽

Cited By ~ 44

Author(s):

Violaine Delorme ◽

Xavier Cayla ◽

Grazyna Faure ◽

Alphonse Garcia ◽

Isabelle Tardieux

Keyword(s):

Toxoplasma Gondii ◽

Actin Polymerization ◽

Casein Kinase Ii ◽

Casein Kinase ◽

Gliding Motility ◽

Actin Dynamics ◽

Central Feature ◽

Parasite Motility

Actin polymerization in Apicomplexa protozoa is central to parasite motility and host cell invasion. Toxofilin has been characterized as a protein that sequesters actin monomers and caps actin filaments in Toxoplasma gondii. Herein, we show that Toxofilin properties in vivo as in vitro depend on its phosphorylation. We identify a novel parasitic type 2C phosphatase that binds the Toxofilin/G-actin complex and a casein kinase II-like activity in the cytosol, both of which modulate the phosphorylation status of Toxofilin serine53. The interplay of these two molecules controls Toxofilin binding of G-actin as well as actin dynamics in vivo. Such functional interactions should play a major role in actin sequestration, a central feature of actin dynamics in Apicomplexa that underlies the spectacular speed and nature of parasite gliding motility.

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Myo1g is required for efficient adhesion and migration of activated B lymphocytes to inguinal lymph nodes

Scientific Reports ◽

10.1038/s41598-021-85477-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

D. Cruz-Zárate ◽

O. López-Ortega ◽

D. A. Girón-Pérez ◽

A. M. Gonzalez-Suarez ◽

J. L. García-Cordero ◽

...

Keyword(s):

Cell Migration ◽

Lymph Node ◽

B Lymphocytes ◽

Dynamic Process ◽

Inguinal Lymph Node ◽

Cytoskeletal Remodeling ◽

And Migration

AbstractCell migration is a dynamic process that involves adhesion molecules and the deformation of the moving cell that depends on cytoskeletal remodeling and actin-modulating proteins such as myosins. In this work, we analyzed the role of the class I Myosin-1 g (Myo1g) in migratory processes of LPS + IL-4 activated B lymphocytes in vivo and in vitro. In vivo, the absence of Myo1g reduced homing of activated B lymphocytes into the inguinal lymph node. Using microchannel chambers and morphology analysis, we found that the lack of Myo1g caused adhesion and chemotaxis defects. Additionally, deficiency in Myo1g causes flaws in adopting a migratory morphology. Our results highlight the importance of Myo1g during B cell migration.

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Vimentin fibers orient traction stress

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1614610114 ◽

2017 ◽

Vol 114 (20) ◽

pp. 5195-5200 ◽

Cited By ~ 50

Author(s):

Nancy Costigliola ◽

Liya Ding ◽

Christoph J. Burckhardt ◽

Sangyoon J. Han ◽

Edgar Gutierrez ◽

...

Keyword(s):

Cell Migration ◽

Single Cell ◽

Graph Matching ◽

Single Cells ◽

Mechanical Strain ◽

Migration Direction ◽

Human Foreskin Fibroblasts ◽

And Migration

The intermediate filament vimentin is required for cells to transition from the epithelial state to the mesenchymal state and migrate as single cells; however, little is known about the specific role of vimentin in the regulation of mesenchymal migration. Vimentin is known to have a significantly greater ability to resist stress without breaking in vitro compared with actin or microtubules, and also to increase cell elasticity in vivo. Therefore, we hypothesized that the presence of vimentin could support the anisotropic mechanical strain of single-cell migration. To study this, we fluorescently labeled vimentin with an mEmerald tag using TALEN genome editing. We observed vimentin architecture in migrating human foreskin fibroblasts and found that network organization varied from long, linear bundles, or “fibers,” to shorter fragments with a mesh-like organization. We developed image analysis tools employing steerable filtering and iterative graph matching to characterize the fibers embedded in the surrounding mesh. Vimentin fibers were aligned with fibroblast branching and migration direction. The presence of the vimentin network was correlated with 10-fold slower local actin retrograde flow rates, as well as spatial homogenization of actin-based forces transmitted to the substrate. Vimentin fibers coaligned with and were required for the anisotropic orientation of traction stresses. These results indicate that the vimentin network acts as a load-bearing superstructure capable of integrating and reorienting actin-based forces. We propose that vimentin's role in cell motility is to govern the alignment of traction stresses that permit single-cell migration.

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