肥胖相关lncRNA-AC092159.2在人脂肪细胞分化中的作用与机制研究

LncRNA AC092159.2 is a new-found long noncoding RNA through lncRNA microarray, which was highly expressed in the obese omental adipose tissue and positively associated with BMI. Our previous study found that AC092159.2 was also highly expressed in differentiated adipocytes, and knockdown of this gene could inhibit adipocyte differentiation by the mechanism which may be associated with recruitment of H3K4 methylase complexes. This study will firstly verify the association between AC092159.2 and obesity. Moreover, we will investigate the function of AC092159.2 in adipocyte differentiation by overexpression and knockdown strategies. Additionally, we will explore the detailed mechanism of AC092159.2 interacted with TMEM18 during adipocyte differentiation. So far there is no report about human AC092159.2 in adipocyte differentiation, thus, this study is of a certain innovation and will provide a new potential target for the prevention and treatment of obesity.

AC092159.2是我们前期应用芯片筛选肥胖与正常体重者脂肪组织中差异非编码RNA时发现的、差异高表达于肥胖者脂肪组织、表达水平与BMI显著正相关的lncRNA。前期研究发现，AC092159.2表达随脂肪细胞分化成熟逐渐增加，沉默AC092159.2可显著抑制人脂肪细胞分化，其机制可能与募集H3K4甲基转移酶复合体调控TMEM18表达有关。本研究拟扩大临床样本，进一步明确AC092159.2与肥胖之间的相关性；采用过表达和敲低策略，进一步系统论证AC092159.2在脂肪细胞分化中的功能；并通过挽救实验策略及RIP、RNA pull-down等技术深入探讨AC092159.2通过调控TMEM18表达参与人脂肪细胞分化的分子机制。目前尚无AC092159.2的报道，本研究将揭示AC092159.2在人脂肪细胞分化中的作用与机制，可为肥胖防治提供潜在靶标。

AC092159.2是我们应用芯片筛选肥胖与正常体重者脂肪组织中差异非编码RNA时发现的、差异高表达于肥胖者脂肪组织、表达水平与BMI显著正相关的lncRNA。本研究通过扩大临床样本明确AC092159.2与肥胖之间的相关性；采用过表达和敲低策略，进一步系统论证AC092159.2在脂肪细胞分化中的功能；并通过挽救实验策略及RIP、RNA pull-down等技术深入探讨AC092159.2通过调控TMEM18表达参与人脂肪细胞分化的分子机制。关于AC092159.2的生物学特征研究发现：①AC092159.2存在 ENST00000445418和 ENST00000435573两个转录本，AC092159.2在皮下和内脏脂肪组织中转录本为ENST00000445418，即明确了研究序列；②AC092159.2在多种组织中具有表达，但在脂肪组织中的表达量较高，在人脂肪细胞分化过程中表达量逐渐增高，且AC092159.2表达量与体重指数呈正相关。③核质分离发现AC092159.2主要分布于细胞核内。关于AC092159.2在人脂肪细胞分化中的功能分析研究发现：①在HPA-v细胞中过表达AC092159.2可明显促进成脂分化，表现为甘油三脂含量明显增高，脂滴增多增大，脂肪分化关键基因表达量显著上调；②在HPA-v细胞中沉默AC092159.2可明显抑制成脂分化，表现为甘油三脂含量明显降低，脂滴减少，脂肪分化关键基因表达量显著下调；③过表达及沉默AC092159.2对HPA-v细胞的细胞增殖、周期和凋亡均没有影响。关于AC092159.2调控人脂肪细胞分化的作用机制探讨研究发现：① TMEM18在超重/肥胖者脂肪组织中显著高表达，且与AC092159.2表达呈显著正相关；HPA-v细胞分化过程中，TMEM18与AC092159.2表达水平均逐渐升高；②在HPA-v细胞中过表达AC092159.2可显著促进TMEM18表达，沉默AC092159.2可显著抑制TMEM18表达。③采用挽救实验策略进一步证实AC092159.2通过调控TMEM18参与HPA-v细胞分化；④荧光素酶报告基因实验进一步证实过表达AC092159.2可以激活TMEM18基因启动子。本研究揭示了AC092159.2在人脂肪细胞分化中的作用与机制，可为肥胖防治提供潜在靶标。