8月20日,Nature 旗下Cell Death " Differentiation杂志在线发表了上海生科院吴家睿研究组和廖侃研究组合作取得的最新研究成果。
随着现代人生活方式的改变,肥胖在世界范围内已经成为影响人类健康的一个重要问题。肥胖容易导致多种疾病的发生,如糖尿病,心血管疾病等。因此,控制过度肥胖是防止多种代谢相关疾病发生的有效渠道。在人体内,肥胖的发生,即脂肪组织的过度增长,是和脂肪细胞的数量增多和体积增大密切相关的。所以,了解在体内脂肪细胞的产生过程,明确脂肪细胞分化中的分子机理,对解决一系列肥胖相关疾病具有重要的现实意义。
吴家睿研究组的裴鸿娟博士和廖侃研究组的姚遥博士通过研究发现,KLF转录因子家族成员KLF9在前脂肪细胞向脂肪细胞分化的过程中起了重要作用。脂肪细胞分化伴随着KLF9表达量的增加,如果抑制KLF9的表达,脂肪细胞的分化将被抑制。研究进一步发现,KLF9在分化的中期结合到一个重要的调控分化的转录因子: PPARγ基因的启动子上,促进PPARγ的表达,从而促进脂肪细胞分化;并且,KLF9可以和另一个转录因子:C/EBPα相互作用,共同上调PPARγ的表达。这个研究结果在现有认识的基础上,进一步阐明了调控脂肪细胞分化的分子机制,为人们解决肥胖和一系列肥胖相关的健康问题提供了新的思路。
该研究工作得到中国科学院、科技部重大科学研究计划、国家自然科学基金委、上海市科委的经费资助。
生物谷推荐英文摘要:
Cell Death " Differentiation , (20 August 2010) | doi:10.1038/cdd.2010.100
Krüppel-like factor KLF9 regulates PPARγ transactivation at the middle stage of adipogenesis
H Pei, Y Yao, Y Yang, K Liao and J-R Wu
Krüppel-like factors (KLFs) as a family of zinc-finger transcription factors involve in the regulation of many physiological processes. In these studies, KLF9 was characterized for its role in adipogenesis. The expression of KLF9 was markedly upregulated during the middle stage of 3T3-L1 adipocyte differentiation, and inhibition of KLF9 by RNAi impaired adipogenesis. Using promoter deletion and mutation analysis, we identified two KLF9-binding sites within the 0.6-kb region of the PPARγ2 proximal promoter, indicating that KLF9 interacts with the PPARγ2 promoter. Furthermore, we found that KLF9 could synergistically activate PPARγ2 promoter by directly interacting with C/EBPα. In addition, overexpression of PPARγ2 rescued the impairment of adipocyte differentiation induced by KLF9 knockdown, which supports that PPARγ2 is a downstream target of KLF9. Collectively, our results indicate KLF9 as a key pro-adipogenic transcription factor through regulation of PPARγ2 expression with C/EBPα at the middle stage of adipogenesis.