| First Author | Ohta Y | Year | 2003 |
| Journal | Genes Cells | Volume | 8 |
| Issue | 10 | Pages | 811-24 |
| PubMed ID | 14531860 | Mgi Jnum | J:89966 |
| Mgi Id | MGI:3042066 | Doi | 10.1046/j.1365-2443.2003.00678.x |
| Citation | Ohta Y, et al. (2003) Differential activities, subcellular distribution and tissue expression patterns of three members of Slingshot family phosphatases that dephosphorylate cofilin. Genes Cells 8(10):811-24 |
| abstractText | BACKGROUND: Cofilin, a key regulator of actin filament dynamics, is inactivated by phosphorylation at Ser-3 by LIM-kinases and is reactivated by dephosphorylation by a family of protein phosphatases, termed Slingshot (SSH). RESULTS: We have identified two novel isoforms of SSHs, termed SSH-2L and SSH-3L and characterized them in comparison with SSH-1L that was previously reported. SSH-1L and SSH-2L, but not SSH-3L, tightly bound to and co-localized with actin filaments. When expressed in cultured cells, SSH-1L, SSH-2L and SSH-3L decreased the level of Ser-3-phosphorylated cofilin (P-cofilin) in cells and suppressed LIM-kinase-induced actin reorganization, although SSH-3L was less effective than SSH-1L and SSH-2L. In cell-free assays, SSH-1L and SSH-2L efficiently dephosphorylated P-cofilin, whereas SSH-3L did do so only weakly. Using deleted mutants of SSH-1L and SSH-2L, we found that the N-terminal and C-terminal extracatalytic regions are critical for cofilin-phosphatase and F-actin-binding activities, respectively. In situ hybridization analyses revealed characteristic patterns of expression of each of the mouse Ssh genes in both neuronal and non-neuronal tissues; in particular, expression of Ssh-3 in epithelial tissues is evident. CONCLUSION: SSH-1L, SSH-2L and SSH-3L have the potential to dephosphorylate P-cofilin, but subcellular distribution, F-actin-binding activity, specific phosphatase activity and expression patterns significantly differ, which suggests that they have related but distinct functions in various cellular and developmental events. |
