TRIM8 regulates Nanog via Hsp90ß-mediated nuclear translocation of STAT3 in embryonic stem cells.

ABSTRACT

TRIM8 is a member of a protein family defined by the presence of a common domain structure composed of a tripartite motif including a RING-finger, one or two B-box domains and a coiled-coil motif. Here, we show that TRIM8 interacts with Hsp90ß, which interacts with STAT3 and selectively downregulates transcription of Nanog in embryonic stem cells. Knock-down of TRIM8 increased phosphorylated STAT3 in the nucleus and also enhanced transcription of Nanog. These findings suggest that TRIM8 modulates translocation of phosphorylated STAT3 into the nucleus through interaction with Hsp90ß and consequently regulates transcription of Nanog in embryonic stem cells.