| First Author | Ding Q | Year | 2007 |
| Journal | Mol Cell Biol | Volume | 27 |
| Issue | 11 | Pages | 4006-17 |
| PubMed ID | 17387146 | Mgi Jnum | J:122206 |
| Mgi Id | MGI:3713587 | Doi | 10.1128/MCB.00620-06 |
| Citation | Ding Q, et al. (2007) Degradation of Mcl-1 by beta-TrCP mediates glycogen synthase kinase 3-induced tumor suppression and chemosensitization. Mol Cell Biol 27(11):4006-17 |
| abstractText | Apoptosis is critical for embryonic development, tissue homeostasis, and tumorigenesis and is determined largely by the Bcl-2 family of antiapoptotic and prosurvival regulators. Here, we report that glycogen synthase kinase 3 (GSK-3) was required for Mcl-1 degradation, and we identified a novel mechanism for proteasome-mediated Mcl-1 turnover in which GSK-3beta associates with and phosphorylates Mcl-1 at one consensus motif ((155)STDG(159)SLPS(163)T; phosphorylation sites are in italics), which will lead to the association of Mcl-1 with the E3 ligase beta-TrCP, and beta-TrCP then facilitates the ubiquitination and degradation of phosphorylated Mcl-1. A variant of Mcl-1 (Mcl-1-3A), which abolishes the phosphorylations by GSK-3beta and then cannot be ubiquitinated by beta-TrCP, is much more stable than wild-type Mcl-1 and able to block the proapoptotic function of GSK-3beta and enhance chemoresistance. Our results indicate that the turnover of Mcl-1 by beta-TrCP is an essential mechanism for GSK-3beta-induced apoptosis and contributes to GSK-3beta-mediated tumor suppression and chemosensitization. |
