Sirtuin 2 (Sirt2) belongs to the NAD⁺-dependent deacetylase family, is more highly expressed than other family members in adipocytes, and plays crucial roles in a wide range of biological processes. However, the mechanisms underlying Sirt2 expression during adipogenesis are poorly studied. In this study, the transcriptional start site (TSS) of Sirt2 was identified and two alternative transcript variants were spliced from Sirt2. The 5′-regulatory region of Sirt2 was also characterized; no TATA-box or CCAAT-box was presented in the 5′-flanking region. Two cytosine-phosphate diester-guanine (CpG) islands were also identified between nucleotides −563 and +4. A dual-luciferase reporter assay revealed that a 178 base pair sequence upstream from the TSS (+1) was the core promoter of Sirt2. Results from a site-directed mutagenesis experiment, electrophoretic mobility shift assay, and chromatin immunoprecipitation assay indicated Yin Yang 1 (YY1) to be a positive regulator of bovine Sirt2 in preadipocytes. YY1 is likely to suppress adipogenesis in two different ways by regulating peroxisome proliferator-activated receptor gamma expression. Our results expand the information on the regulatory network of adipogenesis, which is an important basis for improving beef quality, treating obesity, and other related diseases.

中文翻译：

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阴阳1是必需的前脂肪细胞中的牛Sirt2基因的转录激活。

Sirtuin 2（Sirt2）属于NAD ⁺依赖性脱乙酰基酶家族，在脂肪细胞中比其他家族成员表达更高，并且在广泛的生物学过程中起关键作用。但是，在脂肪形成过程中Sirt2表达的潜在机制研究很少。在这项研究中，Sirt2的转录起始位点（TSS）被确定，并且从Sirt2剪接了两个替代的转录变体。Sirt2的5'调控区还具有特征；在5'侧翼区域未出现TATA框或CCAAT框。在核苷酸-563和+4之间还发现了两个胞嘧啶-磷酸二酯-鸟嘌呤（CpG）岛。双重荧光素酶报告基因测定表明，TSS（+1）上游的178个碱基对序列是Sirt2的核心启动子。定点诱变实验，电泳迁移率迁移测定和染色质免疫沉淀测定的结果表明，Yin Yang 1（YY1）是牛Sirt2的阳性调节剂。在前脂肪细胞中。YY1可能通过调节过氧化物酶体增殖物激活的受体γ的表达，以两种不同的方式抑制脂肪生成。我们的研究结果扩展了脂肪形成调控网络的信息，这是改善牛肉质量，治疗肥胖症和其他相关疾病的重要基础。