Nucleic Acids Research Advance Access published online on June 15, 2009
Nucleic Acids Research, doi:10.1093/nar/gkp516
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Molecular Biology |
PRMT5 is required for cell-cycle progression and p53 tumor suppressor function
Center for Comparative Oncology, University of California at Davis, Davis, CA 95616, USA
*To whom correspondence should be addressed. Tel: +1 530 754 8404; Fax: +1 530 752 6042; Email: xbchen{at}ucdavis.edu
Received March 12, 2009. Accepted May 29, 2009.
Protein arginine methyltransferases (PRMTs) mediate the transfer of methyl groups to arginines in proteins involved in signal transduction, transcriptional regulation and RNA processing. Tumor suppressor p53 coordinates crucial cellular processes, including cell-cycle arrest and DNA repair, in response to stress signals. Post-translational modifications and interactions with co-factors are important to regulate p53 transcriptional activity. To explore whether PRMTs modulate p53 function, we generated multiple cell lines in which PRMT1, CARM1 and PRMT5 are inducibly knocked down. Here, we showed that PRMT5, but not PRMT1 or CARM1, is essential for cell proliferation and PRMT5 deficiency triggers cell-cycle arrest in G1. In addition, PRMT5 is required for p53 expression and induction of p53 targets MDM2 and p21 upon DNA damage. Importantly, we established that PRMT5 knockdown prevents p53 protein synthesis. Furthermore, we found that PRMT5 regulates the expression of translation initiation factor eIF4E and growth suppression mediated upon PRMT5 knockdown is independent of p53 but is dependent on eIF4E. Taken together, we uncovered that arginine methyltransferase PRMT5 is a major pro-survival factor regulating eIF4E expression and p53 translation.