| First Author | Inaba H | Year | 2018 |
| Journal | Biochem Biophys Res Commun | Volume | 498 |
| Issue | 3 | Pages | 544-550 |
| PubMed ID | 29518391 | Mgi Jnum | J:272927 |
| Mgi Id | MGI:6280798 | Doi | 10.1016/j.bbrc.2018.03.016 |
| Citation | Inaba H, et al. (2018) Regulation of keratin 5/14 intermediate filaments by CDK1, Aurora-B, and Rho-kinase. Biochem Biophys Res Commun 498(3):544-550 |
| abstractText | We previously reported that vimentin, GFAP, and desmin (type III intermediate filament [IF] proteins) are mitotically phosphorylated by CDK1, Aurora-B, and Rho-kinase. This phosphorylation is critical for efficient separation of these IFs and completion of cytokinesis. Keratin 5 (K5) and K14 form a heterodimer, which constitutes IF network in basal layer cells of stratified squamous epithelia. Here, we report that the solubility of K5/K14 increased in mitosis. The in vitro assays revealed that three mitotic kinases phosphorylate K5 more than K14. We then identified Thr23/Thr144, Ser30, and Thr159 on murine K5 as major phosphorylation sites for CDK1, Aurora-B, and Rho-kinase, respectively. Using site- and phosphorylation-state-specific antibodies, we demonstrated that K5-Thr23 was phosphorylated in entire cytoplasm from prometaphase to metaphase, whereas K5-Ser30 phosphorylation occurred specifically at the cleavage furrow from anaphase to telophase. Efficient K5/K14-IF separation was impaired by K5 mutations at the sites phosphorylated by these mitotic kinases. K5-Thr23 phosphorylation was widely detected in dividing K5-positive cells of murine individuals. These results suggested that mitotic reorganization of K5/K14-IF network is governed largely through K5 phosphorylation by CDK1, Aurora-B, and Rho-kinase. |
