Transcriptional induction by interferons requires the tyrosine and serine phosphorylation of the STAT1 transcription factor as well as its amino-terminal arginine methylation. Here we show that arginine methylation of STAT1 controls the rate of STAT1 dephosphorylation by modulating its interaction with PIAS1 and the nuclear tyrosine phosphatase TcPTP. Inhibition of STAT1 arginine methylation, or mutation of STAT1 Arg-31, results in a prolonged half-life of STAT1 tyrosine phosphorylation. This effect appears to be mediated by an increased binding of PIAS1 to STAT1 in the absence of STAT1 arginine methylation and a concomitant decrease in the association of STAT1 with TcPTP. Furthermore, inhibitors of arginine methylation require the presence of PIAS1 to exert their negative regulatory effect on the dephosphorylation of STAT1.
SciCrunch® is a data sharing and display platform. Anyone can create a custom portal where they can select searchable subsets of hundreds of data sources, brand their web pages and create their community. SciCrunch® will push data updates automatically to all portals on a weekly basis. User communities can also add their own data to SciCrunch®, however this is not currently a free service.