1
|
Mierke CT, Hayn A, Fischer T. PINCH1 Promotes Fibroblast Migration in Extracellular Matrices and Influences Their Mechanophenotype. Front Cell Dev Biol 2022; 10:869563. [PMID: 35652097 PMCID: PMC9149598 DOI: 10.3389/fcell.2022.869563] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 04/15/2022] [Indexed: 11/13/2022] Open
Abstract
Cell migration performs a critical function in numerous physiological processes, including tissue homeostasis or wound healing after tissue injury, as well as pathological processes that include malignant progression of cancer. The efficiency of cell migration and invasion appears to be based on the mechano-phenotype of the cytoskeleton. The properties of the cytoskeleton depend on internal cytoskeletal and external environmental factors. A reason for this are connections between the cell and its local matrix microenvironment, which are established by cell-matrix adhesion receptors. Upon activation, focal adhesion proteins such as PINCH1 are recruited to sites where focal adhesions form. PINCH1 specifically couples through interactions with ILK, which binds to cell matrix receptors and the actomyosin cytoskeleton. However, the role of PINCH1 in cell mechanics regulating cellular motility in 3D collagen matrices is still unclear. PINCH1 is thought to facilitate 3D motility by regulating cellular mechanical properties, such as stiffness. In this study, PINCH1 wild-type and knock-out cells were examined for their ability to migrate in dense extracellular 3D matrices. Indeed, PINCH1 wild-type cells migrated more numerously and deeper in 3D matrices, compared to knock-out cells. Moreover, cellular deformability was determined, e.g., elastic modulus (stiffness). PINCH1 knock-out cells are more deformable (compliable) than PINCH1 wild-type cells. Migration of both PINCH1−/− cells and PINCH1fl/fl cells was decreased by Latrunculin A inhibition of actin polymerization, suggesting that actin cytoskeletal differences are not responsible for the discrepancy in invasiveness of the two cell types. However, the mechanical phenotype of PINCH1−/− cells may be reflected by Latrunculin A treatment of PINCH1fl/fl cells, as they exhibit resembling deformability to untreated PINCH1−/− cells. Moreover, an apparent mismatch exists between the elongation of the long axis and the contraction of the short axis between PINCH1fl/fl cells and PINCH1−/− cells following Latrunculin A treatment. There is evidence of this indicating a shift in the proxy values for Poisson’s ratio in PINCH1−/− cells compared with PINCH1fl/fl cells. This is probably attributable to modifications in cytoskeletal architecture. The non-muscle myosin II inhibitor Blebbistatin also reduced the cell invasiveness in 3D extracellular matrices but instead caused a stiffening of the cells. Finally, PINCH1 is apparently essential for providing cellular mechanical stiffness through the actin cytoskeleton, which regulates 3D motility.
Collapse
|
2
|
Paensuwan P, Ngoenkam J, Wangteeraprasert A, Pongcharoen S. Essential function of adaptor protein Nck1 in platelet-derived growth factor receptor signaling in human lens epithelial cells. Sci Rep 2022; 12:1063. [PMID: 35058548 PMCID: PMC8776929 DOI: 10.1038/s41598-022-05183-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 01/06/2022] [Indexed: 11/24/2022] Open
Abstract
Binding of platelet-derived growth factor-BB (PDGF-BB) to its cognate receptor (PDGFR) promotes lens epithelial cell (LEC) proliferation and migration. After cataract surgery, these LEC behaviors have been proposed as an influential cause of posterior capsule opacification (PCO). Stimulated PDFGR undergoes dimerization and tyrosine phosphorylation providing docking sites for a SH2-domain-containing noncatalytic region of tyrosine kinase (Nck). Nck is an adaptor protein acting as a linker of the proximal and downstream signaling events. However, the functions of Nck1 protein in LEC have not been investigated so far. We reported here a crucial role of Nck1 protein in regulating PDGFR-mediated LEC activation using LEC with a silenced expression of Nck1 protein. The knockdown of Nck1 suppressed PDGF-BB-stimulated LEC proliferation and migration and disrupted the cell cycle progression especially G1/S transition. LEC lacking Nck1 protein failed to exhibit actin polymerization and membrane protrusions. The downregulation of Nck1 protein in LEC impaired PDGFR‐induced phosphorylation of intracellular signaling proteins, including Erk1/2, Akt, CREB and ATF1, which resulted in inhibition of LEC responses. Therefore, these data suggest that the loss of Nck1 expression may disturb LEC activation and Nck1 may potentially be a drug target to prevent PCO and lens-related disease.
Collapse
Affiliation(s)
- Pussadee Paensuwan
- Department of Optometry, Faculty of Allied Health Sciences, Naresuan University, Tapho District, Phitsanulok, 65000, Thailand.
| | - Jatuporn Ngoenkam
- Department of Microbiology and Parasitology, Faculty of Medical Science, Naresuan University, Tapho District, Phitsanulok, 65000, Thailand
| | - Apirath Wangteeraprasert
- Department of Medicine, Faculty of Medicine, Naresuan University, Tapho District, Phitsanulok, 65000, Thailand
| | - Sutatip Pongcharoen
- Department of Medicine, Faculty of Medicine, Naresuan University, Tapho District, Phitsanulok, 65000, Thailand.
| |
Collapse
|
3
|
Case LB, De Pasquale M, Henry L, Rosen MK. Synergistic phase separation of two pathways promotes integrin clustering and nascent adhesion formation. eLife 2022; 11:e72588. [PMID: 35049497 PMCID: PMC8791637 DOI: 10.7554/elife.72588] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 01/10/2022] [Indexed: 12/14/2022] Open
Abstract
Integrin adhesion complexes (IACs) are integrin-based plasma-membrane-associated compartments where cells sense environmental cues. The physical mechanisms and molecular interactions that mediate initial IAC formation are unclear. We found that both p130Cas ('Cas') and Focal adhesion kinase ('FAK') undergo liquid-liquid phase separation in vitro under physiologic conditions. Cas- and FAK- driven phase separation is sufficient to reconstitute kindlin-dependent integrin clustering in vitro with recombinant mammalian proteins. In vitro condensates and IACs in mouse embryonic fibroblasts (MEFs) exhibit similar sensitivities to environmental perturbations including changes in temperature and pH. Furthermore, mutations that inhibit or enhance phase separation in vitro reduce or increase the number of IACs in MEFs, respectively. Finally, we find that the Cas and FAK pathways act synergistically to promote phase separation, integrin clustering, IAC formation and partitioning of key components in vitro and in cells. We propose that Cas- and FAK-driven phase separation provides an intracellular trigger for integrin clustering and nascent IAC formation.
Collapse
Affiliation(s)
- Lindsay B Case
- Department of Biophysics, Howard Hughes Medical Institute, The University of Texas Southwestern Medical CenterDallasUnited States
- Department of Biology, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Milagros De Pasquale
- Department of Biology, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Lisa Henry
- Department of Biophysics, Howard Hughes Medical Institute, The University of Texas Southwestern Medical CenterDallasUnited States
| | - Michael K Rosen
- Department of Biophysics, Howard Hughes Medical Institute, The University of Texas Southwestern Medical CenterDallasUnited States
| |
Collapse
|
4
|
He P, Sheng J, Qi J, Bai X, Li J, Wang F, Yuan Y, Zheng X. STAT3-induced NCK1 elevation promotes migration of triple-negative breast cancer cells via regulating ERK1/2 signaling. Mol Biol Rep 2021; 49:267-278. [PMID: 34846647 DOI: 10.1007/s11033-021-06868-y] [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: 04/27/2021] [Accepted: 10/21/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND Noncatalytic region of tyrosine kinase 1 (NCK1) plays a key role in extracellular matrix degradation, which is required for the metastasis of triple-negative breast cancer (TNBC). However, the role NCK1 plays in the metastatic progression of TNBC is unknown. METHODS AND RESULTS Based on online databases, NCK1 was found to be highly expressed in TNBC as compared to normal breast-like subjects, which was also confirmed using TNBC cells and a tissue microarray. NCK1 expression gradually decreased with increased tumor stage. High NCK1 expression displayed a poor prognosis in lymph node-positive metastatic TNBC patients, but not in lymph node-negative patients. Using transwell assays and immunoblotting, we confirmed that NCK1 overexpression promoted, while NCK1 downregulation inhibited migration capabilities, as well as the expression of matrix metalloproteinases (MMP2/9), uridylyl phosphate adenosine, and plasminogen activator inhibitor-1 in TNBC cells. Mechanistically, NCK1 upregulation mediated the activation of MMP2/9 through ERK1/2 activity. Signal transducer and activator of transcription 3 (STAT3) was positively correlated with NCK1. STAT3 could directly bind to the promoter region of NCK1 to promote its expression and was accompanied by the elevation of MMP2/9 and ERK1/2 signaling, which were partially abolished by the knockdown of NCK1 in TNBC cells. CONCLUSIONS NCK1 may serve as a diagnostic and prognostic marker of metastatic TNBC. STAT3 upregulation promoted the expression of NCK1, which subsequently induced the migration and activity of MMPs in a ERK1/2 signaling-dependent manner in TNBC cells. NCK1 is a promising target for improving TNBC migration.
Collapse
Affiliation(s)
- Peina He
- Department of Medicine, Pingdingshan University, Chongwen Rd., Xincheng District, Pingdingshan, 467092, China
| | - Jianyun Sheng
- Department of Gynecotokology, Pingdingshan First People's Hospital, Pingdingshan, 410402, China
| | - Jinxu Qi
- Department of Medicine, Pingdingshan University, Chongwen Rd., Xincheng District, Pingdingshan, 467092, China
| | - Xianguang Bai
- Department of Medicine, Pingdingshan University, Chongwen Rd., Xincheng District, Pingdingshan, 467092, China
| | - Jiaxin Li
- Department of Medicine, Pingdingshan University, Chongwen Rd., Xincheng District, Pingdingshan, 467092, China
| | - Fubao Wang
- Department of Gynecotokology, Pingdingshan First People's Hospital, Pingdingshan, 410402, China
| | - Yamin Yuan
- Department of Medicine, Pingdingshan University, Chongwen Rd., Xincheng District, Pingdingshan, 467092, China
| | - Xinhua Zheng
- Department of Medicine, Pingdingshan University, Chongwen Rd., Xincheng District, Pingdingshan, 467092, China.
| |
Collapse
|
5
|
Abstract
The non-catalytic region of tyrosine kinase (Nck) family of adaptors, consisting of Nck1 and Nck2, contributes to selectivity and specificity in the flow of cellular information by recruiting components of signaling networks. Known to play key roles in cytoskeletal remodeling, Nck adaptors modulate host cell-pathogen interactions, immune cell receptor activation, cell adhesion and motility, and intercellular junctions in kidney podocytes. Genetic inactivation of both members of the Nck family results in embryonic lethality; however, viability of mice lacking either one of these adaptors suggests partial functional redundancy. In this Cell Science at a Glance and the accompanying poster, we highlight the molecular organization and functions of the Nck family, focusing on key interactions and pathways, regulation of cellular processes, development, homeostasis and pathogenesis, as well as emerging and non-redundant functions of Nck1 compared to those of Nck2. This article thus aims to provide a timely perspective on the biology of Nck adaptors and their potential as therapeutic targets.
Collapse
Affiliation(s)
- Briana C. Bywaters
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 7783, USA
| | - Gonzalo M. Rivera
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 7783, USA
| |
Collapse
|
6
|
Alfaidi M, Scott ML, Orr AW. Sinner or Saint?: Nck Adaptor Proteins in Vascular Biology. Front Cell Dev Biol 2021; 9:688388. [PMID: 34124074 PMCID: PMC8187788 DOI: 10.3389/fcell.2021.688388] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 04/28/2021] [Indexed: 12/28/2022] Open
Abstract
The Nck family of modular adaptor proteins, including Nck1 and Nck2, link phosphotyrosine signaling to changes in cytoskeletal dynamics and gene expression that critically modulate cellular phenotype. The Nck SH2 domain interacts with phosphotyrosine at dynamic signaling hubs, such as activated growth factor receptors and sites of cell adhesion. The Nck SH3 domains interact with signaling effectors containing proline-rich regions that mediate their activation by upstream kinases. In vascular biology, Nck1 and Nck2 play redundant roles in vascular development and postnatal angiogenesis. However, recent studies suggest that Nck1 and Nck2 differentially regulate cell phenotype in the adult vasculature. Domain-specific interactions likely mediate these isoform-selective effects, and these isolated domains may serve as therapeutic targets to limit specific protein-protein interactions. In this review, we highlight the function of the Nck adaptor proteins, the known differences in domain-selective interactions, and discuss the role of individual Nck isoforms in vascular remodeling and function.
Collapse
Affiliation(s)
- Mabruka Alfaidi
- Department of Pathology and Translational Pathobiology, Louisiana State University Health - Shreveport, Shreveport, LA, United States
| | - Matthew L Scott
- Department of Pathology and Translational Pathobiology, Louisiana State University Health - Shreveport, Shreveport, LA, United States
| | - Anthony Wayne Orr
- Department of Pathology and Translational Pathobiology, Louisiana State University Health - Shreveport, Shreveport, LA, United States.,Department of Cell Biology and Anatomy, LSU Health - Shreveport, Shreveport, LA, United States.,Department of Molecular & Cellular Physiology, LSU Health - Shreveport, Shreveport, LA, United States
| |
Collapse
|
7
|
Kadrmas JL, Beckerle MC, Yoshigi M. Genetic analyses in mouse fibroblast and melanoma cells demonstrate novel roles for PDGF-AB ligand and PDGF receptor alpha. Sci Rep 2020; 10:19303. [PMID: 33168840 PMCID: PMC7653911 DOI: 10.1038/s41598-020-75774-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 10/14/2020] [Indexed: 01/21/2023] Open
Abstract
Platelet Derived Growth Factor Receptor (PDGFR) signaling is a central mitogenic pathway in development, as well as tissue repair and homeostasis. The rules governing the binding of PDGF ligand to the receptor to produce activation and downstream signaling have been well defined over the last several decades. In cultured cells after a period of serum deprivation, treatment with PDGF leads to the rapid formation of dramatic, actin-rich Circular Dorsal Ruffles (CDRs). Using CDRs as a robust visual readout of early PDGFR signaling, we have identified several contradictory elements in the widely accepted model of PDGF activity. Employing CRISPR/Cas9 gene editing to disrupt the Pdgfra gene in two different murine cell lines, we show that in addition to the widely accepted function for PDGFR-beta in CDR formation, PDGFR-alpha is also clearly capable of eliciting CDRs. Moreover, we demonstrate activity for heterodimeric PDGF-AB ligand in the vigorous activation of PDGFR-beta homodimers to produce CDRs. These findings are key to a more complete understanding of PDGF ligand-receptor interactions and their downstream signaling consequences. This knowledge will allow for more rigorous experimental design in future studies of PDGFR signaling and its contributions to development and disease.
Collapse
Affiliation(s)
- Julie L Kadrmas
- Huntsman Cancer Institute, The University of Utah, Salt Lake City, UT, 84112, USA. .,Department of Oncological Sciences, The University of Utah, Salt Lake City, UT, 84112, USA.
| | - Mary C Beckerle
- Huntsman Cancer Institute, The University of Utah, Salt Lake City, UT, 84112, USA. .,School of Biological Sciences, The University of Utah, Salt Lake City, UT, 84112, USA.
| | - Masaaki Yoshigi
- Department of Pediatrics, The University of Utah, Salt Lake City, UT, 84112, USA.
| |
Collapse
|
8
|
Xia P, Huang M, Zhang Y, Xiong X, Yan M, Xiong X, Yu W, Song E. NCK1 promotes the angiogenesis of cervical squamous carcinoma via Rac1/PAK1/MMP2 signal pathway. Gynecol Oncol 2018; 152:387-395. [PMID: 30442385 DOI: 10.1016/j.ygyno.2018.11.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/04/2018] [Accepted: 11/09/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The study was to explore the roles of Nck1 in the angiogenesis of cervical squamous cell carcinoma (CSCC). METHODS mRNA and protein levels were evaluated with real-time quantitative PCR and immunohistochemisty/western blotting respectively. The cancer microvessel density (MVD) was assayed with CD34 endothelial labeling. Nck1 gene knock-in (SiHa-Nck1+) and knock-down (SiHa-Nck1-) were achieved by gene transfection and siRNA respectively. Protein level from cellular supernatant was measured with ELISA. Proliferation, migration and tube formation of the Human Umbilical Vein Endothelial cells (HUVECs) were evaluated by CCK-8 cell viability assay, transwell chamber assay and in vitro Matrigel tubulation assay respectively. RESULTS Nck1 level gradually increased from normal cervical epithelia to high-grade CIN, overexpressed in CSCC and was associated with cancer MVD. The ability of proliferation, migration and tube formation of HUVECs was enhanced in SiHa-Nck1+-treated while decreased in SiHa-NcK1--treated cells compared to SiHa-control-treated cells. Mechanistically, RAC1-GTP, p-PAK1 and MMP2 were increased in SiHa-NCK1+ cells and pretreatment with the Rac1 inhibitor (NSC23766) significantly decreased their levels. Furthermore, inhibition of PAK1 reduced MMP2 level in SiHa-Nck1+ cells whereas the level of Rac1-GTP was unaltered. Also, inhibition of Rac1 or PAK1 impaired angiogenesis-inducing capacity of cancer cells. CONCLUSIONS Nck1 promotes the angiogenesis-inducing capacity of CSCC via the Rac1/PAK1/MMP2 signal pathway.
Collapse
Affiliation(s)
- Pei Xia
- Department of Pathology, Basic Medical College of Nanchang University, Nanchang, Bayi Road, 330006, China
| | - Mingchuan Huang
- Department of Urology, the First Affiliated Hospital of Nanchang University, Nanchang, Yong Wai zheng Road, 330006, China
| | - Yuting Zhang
- Department of Pathology, Basic Medical College of Nanchang University, Nanchang, Bayi Road, 330006, China
| | - Xiujuan Xiong
- Department of Pathology, Basic Medical College of Nanchang University, Nanchang, Bayi Road, 330006, China
| | - Min Yan
- Department of Pathology, Basic Medical College of Nanchang University, Nanchang, Bayi Road, 330006, China
| | - Xiaoliang Xiong
- Department of Pathology, Basic Medical College of Nanchang University, Nanchang, Bayi Road, 330006, China
| | - Weiwei Yu
- Department of Pathology, Basic Medical College of Nanchang University, Nanchang, Bayi Road, 330006, China
| | - Enlin Song
- Department of Pathology, Basic Medical College of Nanchang University, Nanchang, Bayi Road, 330006, China.
| |
Collapse
|
9
|
Dubrac A, Künzel SE, Künzel SH, Li J, Chandran RR, Martin K, Greif DM, Adams RH, Eichmann A. NCK-dependent pericyte migration promotes pathological neovascularization in ischemic retinopathy. Nat Commun 2018; 9:3463. [PMID: 30150707 PMCID: PMC6110853 DOI: 10.1038/s41467-018-05926-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 07/04/2018] [Indexed: 12/20/2022] Open
Abstract
Pericytes are mural cells that surround capillaries and control angiogenesis and capillary barrier function. During sprouting angiogenesis, endothelial cell-derived platelet-derived growth factor-B (PDGF-B) regulates pericyte proliferation and migration via the platelet-derived growth factor receptor-β (PDGFRβ). PDGF-B overexpression has been associated with proliferative retinopathy, but the underlying mechanisms remain poorly understood. Here we show that abnormal, α-SMA-expressing pericytes cover angiogenic sprouts and pathological neovascular tufts (NVTs) in a mouse model of oxygen-induced retinopathy. Genetic lineage tracing demonstrates that pericytes acquire α-SMA expression during NVT formation. Pericyte depletion through inducible endothelial-specific knockout of Pdgf-b decreases NVT formation and impairs revascularization. Inactivation of the NCK1 and NCK2 adaptor proteins inhibits pericyte migration by preventing PDGF-B-induced phosphorylation of PDGFRβ at Y1009 and PAK activation. Loss of Nck1 and Nck2 in mural cells prevents NVT formation and vascular leakage and promotes revascularization, suggesting PDGFRβ-Y1009/NCK signaling as a potential target for the treatment of retinopathies. Pericytes are perivascular cells that regulate blood vessel formation and function. Here Dubrac et al. show that pericyte recruitment contributes to pathological neovascularisation in a mouse model of ischemic retinopathy, and that this depends on the regulation of PDGF-B signaling by NCK adaptor proteins.
Collapse
Affiliation(s)
- Alexandre Dubrac
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, 06511, USA.
| | - Steffen E Künzel
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, 06511, USA
| | - Sandrine H Künzel
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, 06511, USA
| | - Jinyu Li
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, 06511, USA
| | - Rachana Radhamani Chandran
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, 06511, USA
| | - Kathleen Martin
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, 06511, USA
| | - Daniel M Greif
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, 06511, USA
| | - Ralf H Adams
- Department of Tissue Morphogenesis and University of Münster, Faculty of Medicine, Max Planck Institute for Molecular Biomedicine, 48149, Münster, Germany
| | - Anne Eichmann
- Department of Internal Medicine, Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, 06511, USA. .,INSERM U970, Paris Cardiovascular Research Center, 75015, Paris, France. .,Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, 06520, USA.
| |
Collapse
|
10
|
Valdivia A, Goicoechea SM, Awadia S, Zinn A, Garcia-Mata R. Regulation of circular dorsal ruffles, macropinocytosis, and cell migration by RhoG and its exchange factor, Trio. Mol Biol Cell 2017; 28:1768-1781. [PMID: 28468978 PMCID: PMC5491185 DOI: 10.1091/mbc.e16-06-0412] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 04/20/2017] [Accepted: 04/25/2017] [Indexed: 11/11/2022] Open
Abstract
The small GTPase RhoG and its exchange factor, Trio, regulate the formation and size of circular dorsal ruffles and associated functions, including macropinocytosis and cell migration. Circular dorsal ruffles (CDRs) are actin-rich structures that form on the dorsal surface of many mammalian cells in response to growth factor stimulation. CDRs represent a unique type of structure that forms transiently and only once upon stimulation. The formation of CDRs involves a drastic rearrangement of the cytoskeleton, which is regulated by the Rho family of GTPases. So far, only Rac1 has been consistently associated with CDR formation, whereas the role of other GTPases in this process is either lacking or inconclusive. Here we show that RhoG and its exchange factor, Trio, play a role in the regulation of CDR dynamics, particularly by modulating their size. RhoG is activated by Trio downstream of PDGF in a PI3K- and Src-dependent manner. Silencing RhoG expression decreases the number of cells that form CDRs, as well as the area of the CDRs. The regulation of CDR area by RhoG is independent of Rac1 function. In addition, our results show the RhoG plays a role in the cellular functions associated with CDR formation, including macropinocytosis, receptor internalization, and cell migration. Taken together, our results reveal a novel role for RhoG in the regulation of CDRs and the cellular processes associated with their formation.
Collapse
Affiliation(s)
- Alejandra Valdivia
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606.,Division of Cardiology, School of Medicine, Emory University, Atlanta, GA 30322
| | | | - Sahezeel Awadia
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Ashtyn Zinn
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Rafael Garcia-Mata
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| |
Collapse
|
11
|
Abstract
In this review, Meng et al. focus on recent developments in our understanding of the molecular actions of the core Hippo kinase cascade and discuss key open questions in Hippo pathway regulation and function. The Hippo pathway was initially identified in Drosophila melanogaster screens for tissue growth two decades ago and has been a subject extensively studied in both Drosophila and mammals in the last several years. The core of the Hippo pathway consists of a kinase cascade, transcription coactivators, and DNA-binding partners. Recent studies have expanded the Hippo pathway as a complex signaling network with >30 components. This pathway is regulated by intrinsic cell machineries, such as cell–cell contact, cell polarity, and actin cytoskeleton, as well as a wide range of signals, including cellular energy status, mechanical cues, and hormonal signals that act through G-protein-coupled receptors. The major functions of the Hippo pathway have been defined to restrict tissue growth in adults and modulate cell proliferation, differentiation, and migration in developing organs. Furthermore, dysregulation of the Hippo pathway leads to aberrant cell growth and neoplasia. In this review, we focus on recent developments in our understanding of the molecular actions of the core Hippo kinase cascade and discuss key open questions in the regulation and function of the Hippo pathway.
Collapse
Affiliation(s)
- Zhipeng Meng
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Toshiro Moroishi
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Kun-Liang Guan
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| |
Collapse
|
12
|
Miyamoto Y, Torii T, Kawahara K, Tanoue A, Yamauchi J. Dock8 interacts with Nck1 in mediating Schwann cell precursor migration. Biochem Biophys Rep 2016; 6:113-123. [PMID: 28955869 PMCID: PMC5600352 DOI: 10.1016/j.bbrep.2016.03.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 03/22/2016] [Accepted: 03/22/2016] [Indexed: 12/04/2022] Open
Abstract
During embryonic development of the peripheral nervous system (PNS), Schwann cell precursors migrate along neuronal axons to their final destinations, where they will myelinate the axons after birth. While the intercellular signals controlling Schwann cell precursor migration are well studied, the intracellular signals controlling Schwann cell precursor migration remain elusive. Here, using a rat primary cell culture system, we show that Dock8, an atypical Dock180-related guanine-nucleotide exchange factor (GEF) for small GTPases of the Rho family, specifically interacts with Nck1, an adaptor protein composed only of Src homology (SH) domains, to promote Schwann cell precursor migration induced by platelet-derived growth factor (PDGF). Knockdown of Dock8 or Nck1 with its respective siRNA markedly decreases PDGF-induced cell migration, as well as Rho GTPase activation, in precursors. Dock8, through its unique N-terminal proline-rich motif, interacts with the SH3 domain of Nck1, but not with other adaptor proteins composed only of SH domains, e.g. Grb2 and CrkII, and not with the adaptor protein Elmo1. Reintroduction of the proline-rich motif mutant of Dock8 in Dock8 siRNA-transfected Schwann cell precursors fails to restore their migratory abilities, whereas that of wild-type Dock8 does restore these abilities. These results suggest that Nck1 interaction with Dock8 mediates PDGF-induced Schwann cell precursor migration, demonstrating not only that Nck1 and Dock8 are previously unanticipated intracellular signaling molecules involved in the regulation of Schwann cell precursor migration but also that Dock8 is among the genetically-conservative common interaction subset of Dock family proteins consisting only of SH domain adaptor proteins. Dock8, a Rho family GEF, regulates Schwann cell precursor migration. Nck1 adaptor protein regulates Schwann cell precursor migration. Dock8 uniquely interacts with Nck1. The interaction of Dock8 with Nck1 contributes to migration.
Collapse
Affiliation(s)
- Yuki Miyamoto
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
| | - Tomohiro Torii
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
| | - Kazuko Kawahara
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
| | - Akito Tanoue
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
| | - Junji Yamauchi
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan.,Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo, Tokyo 113-8510, Japan
| |
Collapse
|
13
|
Requisite role for Nck adaptors in cardiovascular development, endothelial-to-mesenchymal transition, and directed cell migration. Mol Cell Biol 2015; 35:1573-87. [PMID: 25691664 DOI: 10.1128/mcb.00072-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 02/07/2015] [Indexed: 01/06/2023] Open
Abstract
Development of the cardiovascular system is critically dependent on the ability of endothelial cells (ECs) to reorganize their intracellular actin architecture to facilitate migration, adhesion, and morphogenesis. Nck family cytoskeletal adaptors function as key mediators of actin dynamics in numerous cell types, though their role in EC biology remains largely unexplored. Here, we demonstrate an essential requirement for Nck within ECs. Mouse embryos lacking endothelial Nck1/2 expression develop extensive angiogenic defects that result in lethality at about embryonic day 10. Mutant embryos show immature vascular networks, with decreased vessel branching, aberrant perivascular cell recruitment, and reduced cardiac trabeculation. Strikingly, embryos deficient in endothelial Nck also fail to undergo the endothelial-to-mesenchymal transition (EnMT) required for cardiac valve morphogenesis, with loss of Nck disrupting expression of major EnMT markers, as well as suppressing mesenchymal outgrowth. Furthermore, we show that Nck-null ECs are unable to migrate downstream of vascular endothelial growth factor and angiopoietin-1, and they exhibit profound perturbations in cytoskeletal patterning, with disorganized cellular projections, impaired focal adhesion turnover, and disrupted actin-based signaling. Our collective findings thereby reveal a crucial role for Nck as a master regulator within the endothelium to control actin cytoskeleton organization, vascular network remodeling, and EnMT during cardiovascular development.
Collapse
|
14
|
Buvall L, Rashmi P, Lopez-Rivera E, Andreeva S, Weins A, Wallentin H, Greka A, Mundel P. Proteasomal degradation of Nck1 but not Nck2 regulates RhoA activation and actin dynamics. Nat Commun 2014; 4:2863. [PMID: 24287595 DOI: 10.1038/ncomms3863] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 11/04/2013] [Indexed: 11/09/2022] Open
Abstract
The ubiquitously expressed adapter proteins Nck1/2 interact with a multitude of effector molecules to regulate diverse cellular functions including cytoskeletal dynamics. Here we show that Nck1, but not Nck2, is a substrate of c-Cbl-mediated ubiquitination. We uncover lysine 178 in Nck1 as the evolutionarily conserved ubiquitin acceptor site. We previously reported that synaptopodin, a proline-rich actin-binding protein, induces stress fibres by blocking the Smurf1-mediated ubiquitination of RhoA. We now find that synaptopodin competes with c-Cbl for binding to Nck1, which prevents the ubiquitination of Nck1 by c-Cbl. Gene silencing of c-Cbl restores Nck1 protein abundance and stress fibres in synaptopodin knockdown cells. Similarly, expression of c-Cbl-resistant Nck1(K178R) or Nck2 containing the SH3 domain 2 of Nck1 restores stress fibres in synaptopodin-depleted podocytes through activation of RhoA signalling. These findings reveal proteasomal regulation as a key factor in the distinct and non-redundant effects of Nck on RhoA-mediated actin dynamics.
Collapse
Affiliation(s)
- Lisa Buvall
- 1] Department of Medicine, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts 02129, USA [2]
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Joseph N, Reicher B, David A, Matalon O, Barda-Saad M. Ubiquitylation-dependent downregulation of Nck regulates its functional activity. FEBS Lett 2014; 588:3808-15. [PMID: 25218436 DOI: 10.1016/j.febslet.2014.08.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 08/19/2014] [Accepted: 08/27/2014] [Indexed: 11/18/2022]
Abstract
The Nck adapter protein is involved in key cellular functions, such as actin polymerization and reorganization, serving as a molecular bridge between the surface complex essential for foreign antigen recognition, the T-cell antigen receptor (TCR), and the actin machinery. However, the mechanisms regulating Nck expression and functions are unknown. In this study, we revealed Nck negative regulation and demonstrated that Nck is ubiquitylated following cellular activation. We identified the molecular determinants and mediators involved in this process. Our data suggest that Nck ubiquitylation might serve as a mechanism controlling Nck-mediated effector functions during cellular activation.
Collapse
Affiliation(s)
- Noah Joseph
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Barak Reicher
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Ahuvit David
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Omri Matalon
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Mira Barda-Saad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
| |
Collapse
|
16
|
Chaki SP, Rivera GM. Integration of signaling and cytoskeletal remodeling by Nck in directional cell migration. BIOARCHITECTURE 2013; 3:57-63. [PMID: 23887203 PMCID: PMC3782540 DOI: 10.4161/bioa.25744] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Planar and apical-basal cellular polarization of epithelia and endothelia are crucial during morphogenesis. The establishment of these distinct polarity states and their transitions are regulated by signaling networks that include polarity complexes, Rho GTPases, and phosphoinositides. The spatiotemporal coordination of signaling by these molecules modulates cytoskeletal remodeling and vesicle trafficking to specify membrane domains, a prerequisite for the organization of tissues and organs. Here we present an overview of how activation of the WASp/Arp2/3 pathway of actin remodeling by Nck coordinates directional cell migration and speculate on its role as a signaling integrator in the coordination of cellular processes involved in endothelial cell polarity and vascular lumen formation.
Collapse
Affiliation(s)
- Sankar P Chaki
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX, USA
| | | |
Collapse
|
17
|
Schell C, Baumhakl L, Salou S, Conzelmann AC, Meyer C, Helmstädter M, Wrede C, Grahammer F, Eimer S, Kerjaschki D, Walz G, Snapper S, Huber TB. N-wasp is required for stabilization of podocyte foot processes. J Am Soc Nephrol 2013; 24:713-21. [PMID: 23471198 DOI: 10.1681/asn.2012080844] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Alteration of cortical actin structures is the common final pathway leading to podocyte foot process effacement and proteinuria. The molecular mechanisms that safeguard podocyte foot process architecture and maintain the three-dimensional actin network remain elusive. Here, we demonstrate that neuronal Wiskott-Aldrich syndrome protein (N-WASP), which promotes actin nucleation, is required to stabilize podocyte foot processes. Mice lacking N-WASP specifically in podocytes were born with normal kidney function but developed significant proteinuria 3 weeks after birth, suggesting an important role for N-WASP in maintaining foot processes. In addition, inducing deletion of N-WASP in adult mice resulted in severe proteinuria and kidney failure. Electron microscopy showed an accumulation of electron-dense patches of actin and strikingly altered morphology of podocyte foot processes. Although basic actin-based processes such as cell migration were not affected, primary cultures of N-WASP-deficient podocytes revealed significant impairment of dynamic actin reorganization events, including the formation of circular dorsal ruffles. Taken together, our findings suggest that N-WASP-mediated actin nucleation of branched microfilament networks is specifically required for the maintenance of foot processes, presumably sustaining the mechanical resistance of the filtration barrier.
Collapse
Affiliation(s)
- Christoph Schell
- Renal Division, University Hospital Freiburg, Breisacher Str. 66, 79106 Freiburg, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Locascio LE, Donoghue DJ. KIDs rule: regulatory phosphorylation of RTKs. Trends Biochem Sci 2013; 38:75-84. [PMID: 23312584 DOI: 10.1016/j.tibs.2012.12.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 11/29/2012] [Accepted: 12/03/2012] [Indexed: 01/14/2023]
Abstract
Receptor tyrosine kinases (RTKs) are mediators of multiple cell signaling networks linked to cell growth and differentiation. In general, they exhibit similar overall structure with a ligand-binding extracellular domain and a conserved intracellular tyrosine kinase domain. In many RTKs, the kinase domain is interrupted by a sequence known as the kinase insert domain (KID). In addition to phosphorylation sites within the kinase domain, regulatory phosphorylation also occurs within the KID of several RTKs important in human health and disease. Phosphorylation of specific Tyr or Ser residues within the KID of some RTKs triggers distinct cellular signaling outcomes. Here, we review the functionality of KIDs throughout all RTK families, and provide justification for further study of this often-overlooked domain.
Collapse
Affiliation(s)
- Lauren E Locascio
- Department of Chemistry and Biochemistry, Moores UCSD Cancer Center, University of California San Diego, La Jolla, CA 92093-0367, USA
| | | |
Collapse
|
19
|
Chaki SP, Barhoumi R, Berginski ME, Sreenivasappa H, Trache A, Gomez SM, Rivera GM. Nck enables directional cell migration through the coordination of polarized membrane protrusion with adhesion dynamics. J Cell Sci 2013; 126:1637-49. [DOI: 10.1242/jcs.119610] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Directional migration requires the coordination of cytoskeletal changes essential for cell polarization and adhesion turnover. Extracellular signals that alter tyrosine phosphorylation drive directional migration by inducing reorganization of the actin cytoskeleton. It is recognized that Nck is an important link between tyrosine phosphorylation and actin dynamics, however, the role of Nck in cytoskeletal remodeling during directional migration and the underlying molecular mechanisms remain largely undetermined. In this study, a combination of molecular genetics and quantitative live cell microscopy was used to show that Nck is essential in the establishment of front-back polarity and directional migration of endothelial cells. Time-lapse differential interference contrast and total internal reflection fluorescence microscopy showed that Nck couples the formation of polarized membrane protrusions with their stabilization through the assembly and maturation of cell-substratum adhesions. Measurements by atomic force microscopy showed that Nck also modulates integrin α5β1-fibronectin adhesion force and cell stiffness. Fluorescence resonance energy transfer imaging revealed that Nck depletion results in delocalized and increased activity of Cdc42 and Rac. In contrast, the activity of RhoA and myosin II phosphorylation were reduced by Nck knockdown. Thus, this study identifies Nck as a key coordinator of cytoskeletal changes that enable cell polarization and directional migration which are critical processes in development and disease.
Collapse
|
20
|
Higuchi M, Kihara R, Okazaki T, Aoki I, Suetsugu S, Gotoh Y. Akt1 promotes focal adhesion disassembly and cell motility through phosphorylation of FAK in growth factor-stimulated cells. J Cell Sci 2012; 126:745-55. [PMID: 23264741 DOI: 10.1242/jcs.112722] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The crosstalk between spatial adhesion signals and temporal soluble signals is key in regulating cellular responses such as cell migration. Here we show that soluble growth factors enhance integrin signaling through Akt phosphorylation of FAK at Ser695 and Thr700. PDGF treatment or overexpression of active Akt1 in fibroblasts increased autophosphorylation of FAK at Tyr397, an essential event for integrin turnover and cell migration. Phosphorylation-defective mutants of FAK (S695A and T700A) underwent autophosphorylation at Tyr397 and promoted cell migration in response to the integrin ligand fibronectin, but importantly, not in response to PDGF. This study has unveiled a novel function of Akt as an 'ignition kinase' of FAK in growth factor signaling and may shed light on the mechanism by which growth factors regulate integrin signaling.
Collapse
Affiliation(s)
- Maiko Higuchi
- Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
| | | | | | | | | | | |
Collapse
|
21
|
Itoh T, Hasegawa J. Mechanistic insights into the regulation of circular dorsal ruffle formation. J Biochem 2012; 153:21-9. [PMID: 23175656 DOI: 10.1093/jb/mvs138] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Growth factor stimulations induce dynamic changes in the cytoskeleton beneath the plasma membrane. Among them is the formation of membrane ruffles organized in a circular array, called 'circular dorsal ruffles' (CDRs). Physiological functions of CDRs include downregulation of cell growth by desensitizing the signalling from growth factor receptors as well as rearrangement of adhesion sites at the onset of cell migration. For the formation of CDRs, not only the activators of actin polymerization, such as N-WASP and the Arp2/3-complex, but also membrane deforming proteins with BAR/F-BAR domains are necessary. Small GTPases are also involved in the formation of CDRs by controlling intracellular trafficking through endosomes. Moreover, recent analyses of another circular cytoskeletal structure, podosome rosettes, have revealed common molecular features shared with CDRs. Among them, the roles of PI3-kinase and phosphoinositide 5-phosphatase may hold the key to the induction of these circular structures.
Collapse
Affiliation(s)
- Toshiki Itoh
- Division of Membrane Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Kobe 650-0017, Japan.
| | | |
Collapse
|
22
|
Abstract
Cells construct a number of plasma membrane structures to meet a range of physiological demands. Driven by juxtamembrane actin machinery, these actin-based membrane protrusions are essential for the operation and maintenance of cellular life. They are required for diverse cellular functions, such as directed cell motility, cell spreading, adhesion, and substrate/matrix degradation. Circular dorsal ruffles (CDRs) are one class of such structures characterized as F-actin-rich membrane projections on the apical cell surface. CDRs commence their formation minutes after stimulation as flat, open, and immature ruffles and progressively develop into fully enclosed circular ruffles. These "rings" then mature and contract centrifugally before subsiding. Serving a critical function in receptor internalization and cell migration, CDRs are thus highly dynamic but transient formations. Here, we review the current state of knowledge concerning the regulation of circular dorsal ruffles. We focus specifically on the biochemical pathways leading to CDR formation in order to better define the roles and functions of these enigmatic structures.
Collapse
|
23
|
Lau CL, Perreau VM, Chen MJ, Cate HS, Merlo D, Cheung NS, O'Shea RD, Beart PM. Transcriptomic profiling of astrocytes treated with the Rho kinase inhibitor fasudil reveals cytoskeletal and pro-survival responses. J Cell Physiol 2012; 227:1199-211. [PMID: 21604263 DOI: 10.1002/jcp.22838] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Inhibitors of Rho kinase (ROCK) have potential for management of neurological disorders by inhibition of glial scarring. Since astrocytes play key roles in brain physiology and pathology, we determined changes in the astrocytic transcriptome produced by the ROCK inhibitor Fasudil to obtain mechanistic insights into its beneficial action during brain injury. Cultured murine astrocytes were treated with Fasudil (100 µM) and morphological analyses revealed rapid stellation by 1 h and time-dependent (2-24 h) dissipation of F-actin-labelled stress fibres. Microarray analyses were performed on RNA and the time-course of global gene profiling (2, 6, 12 and 24 h) provided a comprehensive description of transcriptomic changes. Hierarchical clustering of differentially expressed genes and analysis for over-represented gene ontology groups using the DAVID database focused attention on Fasudil-induced changes to major biological processes regulating cellular shape and motility (actin cytoskeleton, axon guidance, transforming growth factor-β (TGFβ) signalling and tight junctions). Bioinformatic analyses of transcriptomic changes revealed how these biological processes contributed to changes in astrocytic motility and cytoskeletal reorganisation. Here genes associated with extracellular matrix were also involved, but unexpected was a subset of alterations (EAAT2, BDNF, anti-oxidant species, metabolic and signalling genes) indicative of adoption by astrocytes of a pro-survival phenotype. Expression profiles of key changes with Fasudil and another ROCK inhibitor Y27632 were validated by real-time PCR. Although effects of ROCK inhibition have been considered to be primarily cytoskeletal via reduction of glial scarring, we demonstrate additional advantageous actions likely to contribute to their ameliorative actions in brain injury.
Collapse
Affiliation(s)
- Chew L Lau
- Florey Neuroscience Institutes, University of Melbourne, Parkville, VIC, Australia
| | | | | | | | | | | | | | | |
Collapse
|
24
|
The adaptor molecule Nck localizes the WAVE complex to promote actin polymerization during CEACAM3-mediated phagocytosis of bacteria. PLoS One 2012; 7:e32808. [PMID: 22448228 PMCID: PMC3308951 DOI: 10.1371/journal.pone.0032808] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 02/02/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND CEACAM3 is a granulocyte receptor mediating the opsonin-independent recognition and phagocytosis of human-restricted CEACAM-binding bacteria. CEACAM3 function depends on an intracellular immunoreceptor tyrosine-based activation motif (ITAM)-like sequence that is tyrosine phosphorylated by Src family kinases upon receptor engagement. The phosphorylated ITAM-like sequence triggers GTP-loading of Rac by directly associating with the guanine nucleotide exchange factor (GEF) Vav. Rac stimulation in turn is critical for actin cytoskeleton rearrangements that generate lamellipodial protrusions and lead to bacterial uptake. PRINCIPAL FINDINGS In our present study we provide biochemical and microscopic evidence that the adaptor proteins Nck1 and Nck2, but not CrkL, Grb2 or SLP-76, bind to tyrosine phosphorylated CEACAM3. The association is phosphorylation-dependent and requires the Nck SH2 domain. Overexpression of the isolated Nck1 SH2 domain, RNAi-mediated knock-down of Nck1, or genetic deletion of Nck1 and Nck2 interfere with CEACAM3-mediated bacterial internalization and with the formation of lamellipodial protrusions. Nck is constitutively associated with WAVE2 and directs the actin nucleation promoting WAVE complex to tyrosine phosphorylated CEACAM3. In turn, dominant-negative WAVE2 as well as shRNA-mediated knock-down of WAVE2 or the WAVE-complex component Nap1 reduce internalization of bacteria. CONCLUSIONS Our results provide novel mechanistic insight into CEACAM3-initiated phagocytosis. We suggest that the CEACAM3 ITAM-like sequence is optimized to co-ordinate a minimal set of cellular factors needed to efficiently trigger actin-based lamellipodial protrusions and rapid pathogen engulfment.
Collapse
|
25
|
Moes MJA, Zhou Y, Boonstra J. Co-localization of the PDGF β-Receptor and Actin during PDGF Stimulation in Mouse Fibroblasts. ACTA ACUST UNITED AC 2012. [DOI: 10.5402/2012/568104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The subcellular localization of the PDGF β-receptor was investigated in relation with PDGF-induced actin and membrane dynamics in mouse C3H10T1/2 fibroblasts. Serum-starved cells exhibit a nonhomogenous distribution of PDGF β-receptors. However, the observed pattern does not resemble the localization of PDGF-induced actin structures. Interestingly, the PDGF β-receptor showed a changed subcellular distribution in relation to the formation of PDGF-BB-induced actin structures. Upon PDGF exposure, PDGF β-receptors were found to accumulate in dorsal circular ruffles. The presence of both macropinosomes and clathrin in the induced circular ruffles suggests that the accumulation of PDGF β-receptors in circular ruffles results in the efficient internalization of PDGF β-receptors.
Collapse
Affiliation(s)
- Maarten J. A. Moes
- Cell Biology, Department of Biology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Yeping Zhou
- Cell Biology, Department of Biology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Johannes Boonstra
- Cell Biology, Department of Biology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| |
Collapse
|
26
|
Haglund CM, Welch MD. Pathogens and polymers: microbe-host interactions illuminate the cytoskeleton. ACTA ACUST UNITED AC 2011; 195:7-17. [PMID: 21969466 PMCID: PMC3187711 DOI: 10.1083/jcb.201103148] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Intracellular pathogens subvert the host cell cytoskeleton to promote their own survival, replication, and dissemination. Study of these microbes has led to many discoveries about host cell biology, including the identification of cytoskeletal proteins, regulatory pathways, and mechanisms of cytoskeletal function. Actin is a common target of bacterial pathogens, but recent work also highlights the use of microtubules, cytoskeletal motors, intermediate filaments, and septins. The study of pathogen interactions with the cytoskeleton has illuminated key cellular processes such as phagocytosis, macropinocytosis, membrane trafficking, motility, autophagy, and signal transduction.
Collapse
Affiliation(s)
- Cat M Haglund
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | | |
Collapse
|
27
|
Zhou L, Zhang Z, Zheng Y, Zhu Y, Wei Z, Xu H, Tang Q, Kong X, Hu L. SKAP2, a novel target of HSF4b, associates with NCK2/F-actin at membrane ruffles and regulates actin reorganization in lens cell. J Cell Mol Med 2011; 15:783-95. [PMID: 20219016 PMCID: PMC3922667 DOI: 10.1111/j.1582-4934.2010.01048.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
In addition to roles in stress response, heat shock factors (HSFs) play crucial roles in differentiation and development. Heat shock transcription factor 4 (HSF4) deficiency leads to defect in lens epithelial cell (LEC) differentiation and cataract formation. However, the mechanism remains obscure. Here, we identified Src kinase-associated phosphoprotein 2 (SKAP2) as a downstream target of HSF4b and it was highly expressed at the anterior tip of lens elongating fibre cells in vivo. The HSF4-deficient lenses showed reduced SKAP2 expression and defects in actin reorganization. The disassembly of stress fibres and formation of cortical actin fibres are critical for the initiation of LEC differentiation. SKAP2 localized at actin-rich ruffles in human LECs (SRA01/04 cells) and knockdown SKAP2 using RNA interference impaired the disassembly of cellular stress fibres in response to fibroblast growth factor (FGF)-b. Overexpression of SKAP2, but not the N-terminal deletion mutant of SKAP2, induced the actin remodelling. We further found that SKAP2 interacted with the SH2 domain of non-catalytic region of tyrosine kinase adaptor protein 2 (NCK2) via its N-terminus. The complex of SKAP2-NCK2-F-actin accumulated at the leading edge of the lamellipodium, where FGF receptors and focal adhesion were also recruited. These results revealed an essential role for HSF4-mediated SKAP2 expression in the regulation of actin reorganization during lens differentiation, likely through a mechanism that SKAP2 anchors the complex of NCK2/focal adhesion to FGF receptors at the lamellipodium in lens epithelial cells.
Collapse
Affiliation(s)
- Li Zhou
- The Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine (SJTUSM), Shanghai, People's Republic of China
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Veevers-Lowe J, Ball SG, Shuttleworth A, Kielty CM. Mesenchymal stem cell migration is regulated by fibronectin through α5β1-integrin-mediated activation of PDGFR-β and potentiation of growth factor signals. J Cell Sci 2011; 124:1288-300. [PMID: 21429937 DOI: 10.1242/jcs.076935] [Citation(s) in RCA: 187] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Cell migration during vascular remodelling is regulated by crosstalk between growth factor receptors and integrin receptors, which together coordinate cytoskeletal and motogenic changes. Here, we report extracellular matrix (ECM)-directed crosstalk between platelet-derived growth factor receptor (PDGFR)-β and α5β1-integrin, which controls the migration of mesenchymal stem (stromal) cells (MSCs). Cell adhesion to fibronectin induced α5β1-integrin-dependent phosphorylation of PDGFR-β in the absence of growth factor stimulation. Phosphorylated PDGFR-β co-immunoprecipitated with α5-integrin and colocalised with α5β1-integrin in the transient tidemarks of focal adhesions. Adhesion to fibronectin also strongly potentiated PDGF-BB-induced PDGFR-β phosphorylation and focal adhesion kinase (FAK) activity, in an α5β1-integrin-dependent manner. PDGFR-β-induced phosphoinositide 3-kinase (PI3K) and Akt activity, actin reorganisation and cell migration were all regulated by fibronectin and α5β1-integrin. This synergistic relationship between α5β1-integrin and PDGFR-β is a fundamental determinant of cell migration. Thus, fibronectin-rich matrices can prime PDGFR-β to recruit mesenchymal cells at sites of vascular remodelling.
Collapse
Affiliation(s)
- Jennifer Veevers-Lowe
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
| | | | | | | |
Collapse
|
29
|
Expression and functional validation of new p38α transcriptional targets in tumorigenesis. Biochem J 2011; 434:549-58. [DOI: 10.1042/bj20101410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
p38α MAPK (mitogen-activated protein kinase) plays an important tumour suppressor role, which is mediated by both its negative effect on cell proliferation and its pro-apoptotic activity. Surprisingly, most tumour suppressor mechanisms co-ordinated by p38α have been reported to occur at the post-translational level. This contrasts with the important role of p38α in the regulation of transcription and the profound changes in gene expression that normally occur during tumorigenesis. We have analysed whole-genome expression profiles of Ras-transformed wild-type and p38α-deficient cells and have identified 202 genes that are potentially regulated by p38α in transformed cells. Expression analysis has confirmed the regulation of these genes by p38α in tumours, and functional validation has identified several of them as probable mediators of the tumour suppressor effect of p38α on Ras-induced transformation. Interestingly, approx. 10% of the genes that are negatively regulated by p38α in transformed cells contribute to EGF (epidermal growth factor) receptor signalling. Our results suggest that inhibition of EGF receptor signalling by transcriptional targets of p38α is an important function of this signalling pathway in the context of tumour suppression.
Collapse
|
30
|
Abella JV, Vaillancourt R, Frigault MM, Ponzo MG, Zuo D, Sangwan V, Larose L, Park M. The Gab1 scaffold regulates RTK-dependent dorsal ruffle formation through the adaptor Nck. J Cell Sci 2010; 123:1306-19. [PMID: 20332103 DOI: 10.1242/jcs.062570] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The polarised distribution of signals downstream from receptor tyrosine kinases (RTKs) regulates fundamental cellular processes that control cell migration, growth and morphogenesis. It is poorly understood how RTKs are involved in the localised signalling and actin remodelling required for these processes. Here, we show that the Gab1 scaffold is essential for the formation of a class of polarised actin microdomain, namely dorsal ruffles, downstream from the Met, EGF and PDGF RTKs. Gab1 associates constitutively with the actin-nucleating factor N-WASP. Following RTK activation, Gab1 recruits Nck, an activator of N-WASP, into a signalling complex localised to dorsal ruffles. Formation of dorsal ruffles requires interaction between Gab1 and Nck, and also requires functional N-WASP. Epithelial cells expressing Gab1DeltaNck (Y407F) exhibit decreased Met-dependent Rac activation, fail to induce dorsal ruffles, and have impaired cell migration and epithelial remodelling. These data show that a Gab1-Nck signalling complex interacts with several RTKs to promote polarised actin remodelling and downstream biological responses.
Collapse
Affiliation(s)
- Jasmine V Abella
- Department of Biochemistry, McGill University, Montréal, Québec H3A 1A1, Canada
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Antoku S, Mayer BJ. Distinct roles for Crk adaptor isoforms in actin reorganization induced by extracellular signals. J Cell Sci 2009; 122:4228-38. [PMID: 19861495 DOI: 10.1242/jcs.054627] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Crk family adaptors, consisting of Src homology 2 (SH2) and SH3 protein-binding domains, mediate assembly of protein complexes in signaling. CrkI, an alternately spliced form of Crk, lacks the regulatory phosphorylation site and C-terminal SH3 domain present in CrkII and CrkL. We used gene silencing combined with mutational analysis to probe the role of Crk adaptors in platelet-derived growth-factor receptor beta (PDGFbetaR) signaling. We demonstrate that Crk adaptors are required for formation of focal adhesions, and for PDGF-stimulated remodeling of the actin cytoskeleton and cell migration. Crk-dependent signaling is crucial during the early stages of PDGFbetaR activation, whereas its termination by Abl family tyrosine kinases is important for turnover of focal adhesions and progression of dorsal-membrane ruffles. CrkII and CrkL preferentially activate the small GTPase Rac1, whereas variants lacking a functional C-terminal SH3 domain, including CrkI, preferentially activate Rap1. Thus, differences in the activity of Crk isoforms, including their effectors and their ability to be downregulated by phosphorylation, are important for coordinating dynamic changes in the actin cytoskeleton in response to extracellular signals.
Collapse
Affiliation(s)
- Susumu Antoku
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, CT 06030-3301, USA
| | | |
Collapse
|
32
|
Jones N, New LA, Fortino MA, Eremina V, Ruston J, Blasutig IM, Aoudjit L, Zou Y, Liu X, Yu GL, Takano T, Quaggin SE, Pawson T. Nck proteins maintain the adult glomerular filtration barrier. J Am Soc Nephrol 2009; 20:1533-43. [PMID: 19443634 DOI: 10.1681/asn.2009010056] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Within the glomerulus, the scaffolding protein nephrin bridges the actin-rich foot processes that extend from adjacent podocytes to form the slit diaphragm. Mutations affecting a number of slit diaphragm proteins, including nephrin, cause glomerular disease through rearrangement of the actin cytoskeleton and disruption of the filtration barrier. We recently established that the Nck family of Src homology 2 (SH2)/SH3 cytoskeletal adaptor proteins can mediate nephrin-dependent actin reorganization. Formation of foot processes requires expression of Nck in developing podocytes, but it is unknown whether Nck maintains podocyte structure and function throughout life. Here, we used an inducible transgenic strategy to delete Nck expression in adult mouse podocytes and found that loss of Nck expression rapidly led to proteinuria, glomerulosclerosis, and altered morphology of foot processes. We also found that podocyte injury reduced phosphorylation of nephrin in adult kidneys. These data suggest that Nck is required to maintain adult podocytes and that phosphotyrosine-based interactions with nephrin may occur in foot processes of resting, mature podocytes.
Collapse
Affiliation(s)
- Nina Jones
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, New Science Complex, Guelph, Ontario, Canada.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Non-compensating roles between Nckalpha and Nckbeta in PDGF-BB signaling to promote human dermal fibroblast migration. J Invest Dermatol 2009; 129:1909-20. [PMID: 19242519 DOI: 10.1038/jid.2008.457] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Platelet-derived growth factor BB (PDGF-BB) is a Food and Drug Administration (FDA)-approved growth factor, acting as a mitogen and motogen of dermal fibroblasts (DFs), for skin wound healing. The two closely related SH2/SH3 adapter proteins, Nckalpha and Nckbeta, connect PDGF-BB signaling to the actin cytoskeleton and cell motility. The mechanism has not been fully understood. In this study, we investigated, side by side, the roles of Nckalpha and Nckbeta in PDGF-BB-stimulated DF migration. We found that cells expressing the PDGFRbeta-Y751F mutant (preventing Nckalpha binding) or PDGFRbeta-Y1009F mutant (preventing Nckbeta binding), DF cells isolated from Nckalpha- or Nckbeta-knockout mice, and primary human DF cells with RNA interference (RNAi) knockdown of the endogenous Nckalpha or Nckbeta all failed to migrate in response to PDGF-BB. Overexpression of the middle SH3 domain of Nckalpha or Nckbeta alone in human DFs also blocked PDGF-BB-induced cell migration. However, neither Nckalpha nor Nckbeta was required for the activation of the PDGF receptor, p21-activated protein kinase (Pak1), AKT, extracellular signal-regulated kinase (ERK) 1/2, or p38MAP by PDGF-BB. Although PDGF-BB stimulated the membrane translocation of both Nckalpha and Nckbeta, Nckalpha appeared to mediate Cdc42 signaling for filopodium formation, whereas Nckbeta mediated Rho signaling to induce stress fibers. Thus, this study has elucidated the independent roles and mechanisms of action of Nckalpha and Nckbeta in DF migration, which is critical for wound healing.
Collapse
|