| First Author | Koh TJ | Year | 2004 |
| Journal | Am J Physiol Cell Physiol | Volume | 286 |
| Issue | 3 | Pages | C713-22 |
| PubMed ID | 14627610 | Mgi Jnum | J:87935 |
| Mgi Id | MGI:3028713 | Doi | 10.1152/ajpcell.00341.2003 |
| Citation | Koh TJ, et al. (2004) Cytoskeletal disruption and small heat shock protein translocation immediately after lengthening contractions. Am J Physiol Cell Physiol 286(3):C713-22 |
| abstractText | The purposes of this study were to determine whether, immediately after lengthening contractions, 1) levels of specific force-transmitting cytoskeletal elements are reduced in skeletal muscle cells and 2) cytosolic small heat shock proteins (HSPs) translocate to structures prone to disruption. Western blot analysis demonstrated decreased concentrations of z-disk proteins alpha-actinin and plectin and membrane scaffolding proteins dystrophin and beta-spectrin in muscle exposed to lengthening contractions compared with contralateral control muscle. Lengthening contractions also resulted in immediate translocation of constitutively expressed HSP25 and alphaB-crystallin from the soluble to the insoluble fraction of muscle homogenates, and cryosections showed translocation from a diffuse, cytosolic localization to striations that corresponded to z-disks. Lengthening contraction-induced translocation of HSP25 and alphaB-crystallin was associated with phosphorylation of these small HSPs, which may trigger their protective activity. In summary, these findings demonstrate loss of z-disk and membrane scaffolding proteins immediately after lengthening contractions, and concomitant translocation of HSP25 and alphaB-crystallin to the z-disk, which may help to stabilize or repair cytoskeletal elements at this site. |
