RNAi knockdown of the focal adhesion protein TES reveals its role in actin stress fibre organisation.
TES was originally identified as a candidate tumour suppressor gene and has subsequently been found to encode a novel focal adhesion protein. As well as localising to cell-matrix adhesions, TES localises to cell-cell contacts and to actin stress fibres. TES interacts with a variety of cytoskeletal proteins including zyxin, mena, VASP, talin and actin. There is evidence that TES may function in actin-dependent processes as overexpression of TES results in increased cell spreading and decreased cell motility. Together with TES's interacting partners, these data suggest that TES might be involved in regulation of the actin cytoskeleton. Here, for the first time, we have used RNAi to successfully knockdown TES in HeLa cells and we demonstrate that loss of TES from focal adhesions results in loss of actin stress fibres. Similarly, and as previously reported, RNAi-mediated knockdown of zyxin results in loss of actin stress fibres. TES siRNA treated cells show reduced RhoA activity, suggesting that the Rho GTPase pathway may be involved in the TES RNAi-induced loss of stress fibres. We have also used RNAi to examine the requirement of TES and zyxin for each other's localisation at focal adhesions, and we propose a hierarchy of recruitment, with zyxin being first, followed by VASP and then TES. Cell Motil.
Griffith
Elen
E
Cancer Research UK Laboratories, Beatson Institute for Cancer Research, Glasgow, United Kingdom. eg66j@clinmed.gla.ac.uk
Coutts
Amanda S
AS
Black
Donald M
DM
D000199:Actins / Q000187:drug effects / Q000648:ultrastructure*; D015815:Cell Adhesion Molecules / Q000378:metabolism; D003598:Cytoskeletal Proteins; D022001:Focal Adhesions / Q000502:physiology*; D006023:Glycoproteins / Q000096:biosynthesis; D006367:HeLa Cells; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000502:physiology*; D006801:Humans; D060588:LIM Domain Proteins; D008840:Microfilament Proteins; D008954:Models, Biological; D010750:Phosphoproteins / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000502:physiology; D016601:RNA-Binding Proteins; D022502:Stress Fibers / Q000648:ultrastructure*; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis / Q000502:physiology*; D060589:Zyxin; D020742:rhoA GTP-Binding Protein / Q000378:metabolism; D000098662:Vasodilator-Stimulated Phosphoprotein
D000199:Actins; D015815:Cell Adhesion Molecules; D003598:Cytoskeletal Proteins; D006023:Glycoproteins; D018398:Homeodomain Proteins; D060588:LIM Domain Proteins; D008840:Microfilament Proteins; D010750:Phosphoproteins; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; C429688:TES protein, human; D025521:Tumor Suppressor Proteins; C092842:ZYX protein, human; D060589:Zyxin; D000098662:Vasodilator-Stimulated Phosphoprotein; D020742:rhoA GTP-Binding Protein