Itoh Toshinari, Miyake Katsuhide, Iijima Shinji
Department of Biotechnology, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Biochem Biophys Res Commun. 2008 Feb 15;366(3):827-33. doi: 10.1016/j.bbrc.2007.12.026. Epub 2007 Dec 17.
The chromatin remodeling complex SWI/SNF exclusively contains BRG1 or BRM as an ATPase subunit, but the physiological relevance of these ATPases is not yet clear. Here, we studied the developmental regulation of the brm gene. A differentiation-specific up-regulation of BRM expression was observed with P19, F9 and C2C12 cells as with neural cells and hepatocytes. The promoter region of brm contains two putative binding sites for CCAAT enhancer binding protein beta (C/EBPbeta). Each site partially overlapped with binding sites for GATAs. C/EBPbeta stimulated the transcriptional activity of the brm promoter but GATA2 and 3 down-regulated the expression. C/EBPbeta bound to the proximal sequences of the promoter in differentiated cells and was replaced by GATAs which bound to the overlapping sites in the undifferentiated state. C/EBPbeta and GATAs may developmentally regulate the expression of brm by mutually exclusive binding.
染色质重塑复合物SWI/SNF仅包含BRG1或BRM作为ATP酶亚基，但这些ATP酶的生理相关性尚不清楚。在此，我们研究了brm基因的发育调控。在P19、F9和C2C12细胞中，与神经细胞和肝细胞一样，观察到BRM表达的分化特异性上调。brm的启动子区域包含两个假定的CCAAT增强子结合蛋白β（C/EBPβ）结合位点。每个位点部分与GATA的结合位点重叠。C/EBPβ刺激brm启动子的转录活性，但GATA2和3下调其表达。C/EBPβ在分化细胞中与启动子的近端序列结合，并被在未分化状态下与重叠位点结合的GATA取代。C/EBPβ和GATA可能通过相互排斥的结合在发育过程中调节brm的表达。
