| First Author | Bianchi-Smiraglia A | Year | 2013 |
| Journal | Cell Cycle | Volume | 12 |
| Issue | 21 | Pages | 3377-89 |
| PubMed ID | 24036928 | Mgi Jnum | J:213085 |
| Mgi Id | MGI:5582864 | Doi | 10.4161/cc.26388 |
| Citation | Bianchi-Smiraglia A, et al. (2013) Integrin-beta5 and zyxin mediate formation of ventral stress fibers in response to transforming growth factor beta. Cell Cycle 12(21):3377-89 |
| abstractText | Cell adhesion to the extracellular matrix is an essential element of various biological processes. TGF-beta cytokines regulate the matrix components and cell-matrix adhesions. The present study investigates the molecular organization of TGF-beta-induced matrix adhesions. The study demonstrates that in various mouse and human epithelial cells TGF-beta induces cellular structures containing 2 matrix adhesions bridged by a stretch of actin fibers. These structures are similar to ventral stress fibers (VSFs). Suppression of integrin-beta5 by RNA interference reduces VSFs in majority of cells (> 75%), while overexpression of integrin-beta5 fragments revealed a critical role of a distinct sequence in the cytoplasmic domain of integrin-beta5 in the VSF structures. In addition, the integrity of actin fibers and Src kinase activity contribute to integrin-beta5-mediated signaling and VSF formation. TGF-beta-Smad signaling upregulates actin-regulatory proteins, such as caldesmon, zyxin, and zyxin-binding protein Csrp1 in mouse and human epithelial cells. Suppression of zyxin markedly inhibits formation of VSFs in response to TGF-beta and integrin-beta5. Zyxin is localized at actin fibers and matrix adhesions of VSFs and might bridge integrin-beta5-mediated adhesions to actin fibers. These findings provide a platform for defining the molecular mechanism regulating the organization and activities of VSFs in response to TGF-beta. |
