| First Author | Tonami K | Year | 2007 |
| Journal | Mol Cell Biol | Volume | 27 |
| Issue | 7 | Pages | 2548-61 |
| PubMed ID | 17210638 | Mgi Jnum | J:121389 |
| Mgi Id | MGI:3709943 | Doi | 10.1128/MCB.00992-06 |
| Citation | Tonami K, et al. (2007) Calpain 6 is involved in microtubule stabilization and cytoskeletal organization. Mol Cell Biol 27(7):2548-61 |
| abstractText | The calpains are a family of Ca(2+)-dependent cysteine proteases implicated in various biological processes. In this family, calpain 6 (Capn6) is unique in that it lacks the active-site cysteine residues requisite for protease activity. During the search for genes downstream of the endothelin 1 (ET-1) signaling in pharyngeal-arch development, we identified Capn6. After confirming that the expression of Capn6 in pharyngeal arches is downregulated in ET-1-null embryos by in situ hybridization, we investigated its function. In Capn6-transfected cells, cytokinesis was retarded and was often aborted to yield multinucleated cells. Capn6 overexpression also caused the formation of microtubule bundles rich in acetylated alpha-tubulin and resistant to the depolymerizing activity of nocodazole. Green fluorescent protein-Capn6 overexpression, immunostaining for endogenous Capn6, and biochemical analysis demonstrated interaction between Capn6 and microtubules, which appeared to be mainly mediated by domain III. Furthermore, RNA interference-mediated Capn6 inactivation caused microtubule instability with a loss of acetylated alpha-tubulin and induced actin reorganization, resulting in lamellipodium formation with membrane ruffling. Taken together, these results indicate that Capn6 is a microtubule-stabilizing protein expressed in embryonic tissues that may be involved in the regulation of microtubule dynamics and cytoskeletal organization. |
