| First Author | Gingras AR | Year | 2010 |
| Journal | J Biol Chem | Volume | 285 |
| Issue | 38 | Pages | 29577-87 |
| PubMed ID | 20610383 | Mgi Jnum | J:240268 |
| Mgi Id | MGI:5882878 | Doi | 10.1074/jbc.M109.095455 |
| Citation | Gingras AR, et al. (2010) Central region of talin has a unique fold that binds vinculin and actin. J Biol Chem 285(38):29577-87 |
| abstractText | Talin is an adaptor protein that couples integrins to F-actin. Structural studies show that the N-terminal talin head contains an atypical FERM domain, whereas the N- and C-terminal parts of the talin rod include a series of alpha-helical bundles. However, determining the structure of the central part of the rod has proved problematic. Residues 1359-1659 are homologous to the MESDc1 gene product, and we therefore expressed this region of talin in Escherichia coli. The crystal structure shows a unique fold comprised of a 5- and 4-helix bundle. The 5-helix bundle is composed of nonsequential helices due to insertion of the 4-helix bundle into the loop at the C terminus of helix alpha3. The linker connecting the bundles forms a two-stranded anti-parallel beta-sheet likely limiting the relative movement of the two bundles. Because the 5-helix bundle contains the N and C termini of this module, we propose that it is linked by short loops to adjacent bundles, whereas the 4-helix bundle protrudes from the rod. This suggests the 4-helix bundle has a unique role, and its pI (7.8) is higher than other rod domains. Both helical bundles contain vinculin-binding sites but that in the isolated 5-helix bundle is cryptic, whereas that in the isolated 4-helix bundle is constitutively active. In contrast, both bundles are required for actin binding. Finally, we show that the MESDc1 protein, which is predicted to have a similar fold, is a novel actin-binding protein. |
