| First Author | Nakayama K | Year | 2003 |
| Journal | Proc Natl Acad Sci U S A | Volume | 100 |
| Issue | 15 | Pages | 8752-7 |
| PubMed ID | 12843402 | Mgi Jnum | J:84639 |
| Mgi Id | MGI:2668774 | Doi | 10.1073/pnas.1133216100 |
| Citation | Nakayama K, et al. (2003) Impaired degradation of inhibitory subunit of NF-kappa B (I kappa B) and beta-catenin as a result of targeted disruption of the beta-TrCP1 gene. Proc Natl Acad Sci U S A 100(15):8752-7 |
| abstractText | beta-TrCP1 (also known as Fbw1a or FWD1) is the F-box protein component of an Skp1/Cul1/F-box (SCF)-type ubiquitin ligase complex. Although biochemical studies have suggested that beta-TrCP1 targets inhibitory subunit of NF-kappa B(I kappa B) proteins and beta-catenin for ubiquitylation, the physiological role of beta-TrCP1 in mammals has remained unclear. We have now generated mice deficient in beta-TrCP1 and shown that the degradation of I kappa B alpha and I kappa B beta is reproducibly, but not completely, impaired in the cells of these animals. The nuclear translocation and DNA-binding activity of NF-kappa B as well as the ability of this transcription factor to activate a luciferase reporter gene were also inhibited in beta-TrCP1-/- cells compared with those apparent in wild-type cells. The subcellular localization of beta-catenin was altered markedly in beta-TrCP1-/- cells. Furthermore, the rate of proliferation was reduced and both cell size and the percentage of polyploid cells were increased in embryonic fibroblasts derived from beta-TrCP1-/- mice compared with the corresponding wild-type cells. These results suggest that beta-TrCP1 contributes to, but is not absolutely required for, the degradation of I kappa B and beta-catenin and the consequent regulation of the NF-kappa B and Wnt signaling pathways, respectively. In addition, they implicate beta-TrCP1 in the maintenance of ploidy during cell-cycle progression. |
