Okumura Fumihiko, Okumura Akiko J, Matsumoto Masaki, Nakayama Keiichi I, Hatakeyama Shigetsugu
Department of Biochemistry, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido 060-8638, Japan.
Biochim Biophys Acta. 2011 Oct;1813(10):1784-92. doi: 10.1016/j.bbamcr.2011.05.013. Epub 2011 Jun 2.
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 Hsp90β, 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 Hsp90β and consequently regulates transcription of Nanog in embryonic stem cells.
TRIM8是一个蛋白质家族的成员，该家族由一个共同的结构域定义，该结构域由一个包含RING指结构、一个或两个B盒结构域和一个卷曲螺旋基序的三联基序组成。在此，我们表明TRIM8与Hsp90β相互作用，Hsp90β与STAT3相互作用并选择性地下调胚胎干细胞中Nanog的转录。敲低TRIM8会增加细胞核中磷酸化STAT3的水平，同时也增强Nanog的转录。这些发现表明，TRIM8通过与Hsp90β相互作用调节磷酸化STAT3向细胞核的转运，从而在胚胎干细胞中调节Nanog的转录。
