First Author | Buck M | Year | 1999 |
Journal | Mol Cell | Volume | 4 |
Issue | 6 | Pages | 1087-92 |
PubMed ID | 10635333 | Mgi Jnum | J:133506 |
Mgi Id | MGI:3778721 | Doi | 10.1016/s1097-2765(00)80237-3 |
Citation | Buck M, et al. (1999) Phosphorylation of rat serine 105 or mouse threonine 217 in C/EBP beta is required for hepatocyte proliferation induced by TGF alpha. Mol Cell 4(6):1087-92 |
abstractText | We report that TGF alpha induces activation of the p90 ribosomal S kinase (RSK), which results in the phosphorylation of rat C/EBP beta on Ser-105 and of mouse C/EBP beta on Thr-217 and concomitantly stimulates proliferation in differentiated hepatocytes. Moreover, C/EBP beta-/- mouse hepatocytes respond to TGF alpha when wild-type C/EBP beta is reexpressed, whereas they remain refractory to the growth effect of TGF alpha when expressing phosphoacceptor mutants rat C/EBP beta Ala-105 or mouse C/EBP beta Ala-217. In contrast, C/EBP beta-/- hepatocytes expressing the phosphorylation mimic mutants, rat C/EBP beta Asp-105 or mouse C/EBP beta Glu-217, exhibited marked proliferation in the absence of TGF alpha. Thus, a site-specific phosphorylation of the transcription factor C/EBP beta is critical for hepatocyte proliferation induced by TGF alpha and other stimuli that activate RSK. |