First Author | Briata P | Year | 2005 |
Journal | Mol Cell | Volume | 20 |
Issue | 6 | Pages | 891-903 |
PubMed ID | 16364914 | Mgi Jnum | J:168204 |
Mgi Id | MGI:4887337 | Doi | 10.1016/j.molcel.2005.10.021 |
Citation | Briata P, et al. (2005) p38-dependent phosphorylation of the mRNA decay-promoting factor KSRP controls the stability of select myogenic transcripts. Mol Cell 20(6):891-903 |
abstractText | Transcriptional and posttranscriptional processes regulate expression of genetic networks in response to environmental cues. The extracellular signal-activated p38 MAP kinase (p38) pathway plays a fundamental role in conversion of myoblasts to differentiated myocytes. p38 phosphorylates specific transcription factors and chromatin-associated proteins promoting assembly of the myogenic transcriptome. Here, we demonstrate that p38 alpha and beta isoforms also control muscle-gene expression posttranscriptionally, by stabilizing critical myogenic transcripts. KSRP, an important factor for AU-rich element (ARE)-directed mRNA decay, undergoes p38-dependent phosphorylation during muscle differentiation. KSRP phosphorylated by p38 displays compromised binding to ARE-containing transcripts and fails to promote their rapid decay, although it retains the ability to interact with the mRNA degradation machinery. Overexpression of KSRP selectively impairs induction of ARE-containing early myogenic transcripts, without affecting p38-mediated transcriptional responses. Our results uncover an unanticipated role for KSRP in establishing a biochemical link between differentiation-activated p38 signaling and turnover of myogenic mRNAs. |