长链非编码RNA HARL7在人脂肪细胞分化中的作用与机制研究

LncRNA HARL7 is highly expressed in human mature adipocytes by differential lncRNA expression profile. Our preliminary experiments confirmed that downregulation of HARL7 inhibited human adipocyte differentiation. Further bioinformatics analysis and studies showed that HARL7 was related with miR-155 and PPARγ in adipogenesis by affecting their expression. Therefore, it is suggested that HARL7 may promote the differentiation of human adipocytes through miR-155/PPARγ. In this study，we will investigate the role of HARL7 in human adipocyte differentiation by over-expression and knockdown strategies. Additionally, rescue strategy, luciferase reporter genes, RNA pull-down, and RIP will be conducted to elucidate the detailed mechanism of HARL7 interacted with miR-155/PPARγ during adipocyte differentiation. So far no reports were about HARL7, thus, this study will reveal the function and molecular mechanism of HARL7 in human adipocyte differentiation, which can provide new opportunities for the treatment of obesity.

HARL7是我们通过芯片发现差异高表达于人成熟脂肪细胞、肥胖人群脂肪组织且功能未知的lncRNA。前期实验证实HARL7表达沉默可抑制人脂肪细胞分化。生物信息学分析提示miR-155是HARL7潜在的下游靶基因，进一步实验证实，沉默HARL7表达后，miR-155的表达上调、PPARγ的表达下调，其效应与HARL7竞争性吸附miR-155，调控PPARγ有关。本研究拟选用过表达和沉默策略，全面阐明HARL7在人脂肪细胞分化中的作用；并通过挽救实验，应用荧光素酶报告基因、RNA pull-down、RIP等技术进一步探讨HARL7下游作用机制，论证HARL7竞争性吸附miR-155，调控PPARγ的表达进而促进人脂肪细胞分化的具体分子机制。迄今未见HARL7的报道，本研究将揭示HARL7在人脂肪细胞分化中的作用与分子机制，为肥胖的防治提供理论依据和实验证据。

lncRNA HARL7是我们通过芯片发现的差异高表达于人成熟脂肪细胞、肥胖人群脂肪组织且功能未知的lncRNA。以人白色脂肪细胞作为研究工具，通过生物信息学分析及定量PCR等技术探讨了HARL7的生物学特征及其肥胖相关性，发现HARL7表达沉默可抑制人脂肪细胞分化。核质分离发现HARL7主要分布于细胞质，结合生物信息学分析，提示miR-155是HARL7潜在的下游靶基因。在人脂肪细胞分化过程及不同人群脂肪组织中检测HARL7与miR-155、PPARγ的表达水平，发现三者的表达水平存在相关性。进一步检测发现沉默HARL7表达可上调miR-155的表达、降低PPARγ的表达。通过挽救策略在人脂肪细胞中同时沉默HARL7和miR-155，结果显示HARL7表达沉默抑制脂肪细胞分化的作用可被miR-155沉默减弱；同时采用荧光素酶报告基因实验进一步证实了HARL7作为ceRNA，竞争性吸附miR-155、调控PPARγ表达，初步论证了HARL7通过miR-155促进人脂肪细胞分化。本研究首次阐明了HARL7在人脂肪细胞分化和肥胖中分化中的作用与分子机制，为肥胖的防治提供理论依据和实验证据。