Talin is a cytoskeletal protein that plays a critical role in the formation of cell adhesions and regulation of integrin signalling. It activates integrins, couples them to F-actin, and recruits vinculin to focal adhesions [1-5]. It is a long protein ...
Talin is a cytoskeletal protein that plays a critical role in the formation of cell adhesions and regulation of integrin signalling. It activates integrins, couples them to F-actin, and recruits vinculin to focal adhesions [1-5]. It is a long protein comprising an N-terminal globular head and a long C-terminal rod which has 13 helical bundles (R1-R13) organized into a compact cluster of four-helix bundles (R2-R4) within a linear chain of five-helix bundles. Nine of the helical bundles contain vinculin-binding sites (VBS), one of them is R4, represented in this entry [2].
Vinculin binding sites are predominantly found in talin and talin-like molecules, enabling binding of vinculin to talin, stabilising integrin-mediated cell-matrix junctions. Talin, in turn, links integrins to the actin cytoskeleton. The consensus seq ...
Vinculin binding sites are predominantly found in talin and talin-like molecules, enabling binding of vinculin to talin, stabilising integrin-mediated cell-matrix junctions. Talin, in turn, links integrins to the actin cytoskeleton. The consensus sequence for Vinculin binding sites is LxxAAxxVAxxVxxLIxxA, with a secondary structure prediction of four amphipathic helices. The hydrophobic residues that define the VBS are themselves 'masked' and are buried in the core of a series of helical bundles that make up the talin rod [1].
Members of this family adopt a structure consisting of five alpha helices that fold into a bundle. They contain a Vinculin binding site (VBS) composed of a hydrophobic surface spanning five turns of helix four. Activation of the VBS causes subsequent ...
Members of this family adopt a structure consisting of five alpha helices that fold into a bundle. They contain a Vinculin binding site (VBS) composed of a hydrophobic surface spanning five turns of helix four. Activation of the VBS causes subsequent recruitment of Vinculin, which enables maturation of small integrin/talin complexes into more stable adhesions. Formation of the complex between VBS and Vinculin requires prior unfolding of this middle domain: once released from the talin hydrophobic core, the VBS helix is then available to induce the 'bundle conversion' conformational change within the vinculin head domain thereby displacing the intramolecular interaction with the vinculin tail, allowing vinculin to bind actin [1].
