Zeng Jun, Hu Jiongyu, Lian Yu, Jiang Youzhao, Chen Bing
Department of Endocrinology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
Department of Endocrinology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
Gene. 2018 Jan 30;641:190-195. doi: 10.1016/j.gene.2017.10.066. Epub 2017 Oct 21.
Secreted frizzled-related protein 5 (SFRP5) is a newly identified adipokine. SFRP5 expression increases during the differentiation and maturation of adipocytes, but the factors regulating SFRP5 expression during this process remain unclear. This study showed that peroxisome proliferator-activated receptor γ (PPARγ) adenovirus transfection could enhance the SFRP5 expression of 3T3-L1 adipocytes. Three potential binding sites of PPARγ in the SFRP5 promoter domain were found by bioinformatics analysis. Luciferase reporter gene assay demonstrated that PPARγ regulated the activity of the SFRP5 promoter through cis-acting elements at -2,284--1,500bp. Further experiments verified that PPARγ could specifically bind to the SFRP5 promoter at -2,284--2,263bp using chromatin immunoprecipitation and electrophoretic mobility shift assay. These results suggest that SFRP5 be a target gene of PPARγ, and its expression may be under the transcriptional regulation of PPARγ.
分泌型卷曲相关蛋白5（SFRP5）是一种新发现的脂肪因子。SFRP5的表达在脂肪细胞分化和成熟过程中增加，但在此过程中调节SFRP5表达的因素仍不清楚。本研究表明，过氧化物酶体增殖物激活受体γ（PPARγ）腺病毒转染可增强3T3-L1脂肪细胞中SFRP5的表达。通过生物信息学分析在SFRP5启动子区域发现了PPARγ的三个潜在结合位点。荧光素酶报告基因检测表明，PPARγ通过-2284至-1500bp处的顺式作用元件调节SFRP5启动子的活性。进一步的实验通过染色质免疫沉淀和电泳迁移率变动分析验证了PPARγ可以特异性结合-2284至-2263bp处的SFRP5启动子。这些结果表明SFRP5是PPARγ的靶基因，其表达可能受PPARγ的转录调控。
