Abstract：
Obesity is one of the significant health challenges in the world and is highly associated with abnormal adipogenesis. TG-interacting factor 1 (TGIF1) is essential for differentiating murine adipocytes and human adipose tissue-derived stem cells. However, the mode of action needs to be better elucidated. To investigate the roles of TGIF1 in differentiation in-depth, CRISPR/Cas9 knockout technology was performed to generate TGIF1-silenced preadipocytes. The absence of TGIF1 in 3 T3-F442A preadipocytes abolished lipid accumulation throughout the differentiation using Oil Red O staining. Conversely, we established 3 T3-F442A preadipocytes stably expressing TGIF1 and doxycycline-inducible TGIF1 in TGIF1-silenced 3 T3-F442A preadipocytes. Remarkably, the induction of TGIF1 by doxycycline during the initial differentiation phase successfully promoted lipid accumulation in TGIF1-silenced 3 T3-F442A cells. We further explored the mechanisms of TGIF1 in early differentiation. We demonstrated that TGIF1 promoted the mitotic clonal expansion via upregulation of CCAAT/enhancer-binding proteins β expression, interruption with peroxisome proliferators activated receptor γ downstream regulation, and inhibition of p27kip1 expression. In conclusion, we strengthen the pivotal roles of TGIF1 in early differentiation, which might contribute to resolving obesity-associated metabolic syndromes.
摘要：
肥胖是世界上重大的健康挑战之一,并且与异常的脂肪形成高度相关。TG相互作用因子1（TGIF1）对于分化鼠脂肪细胞和人脂肪组织来源的干细胞至关重要。然而,行动模式需要更好地阐明。为了深入研究TGIF1在分化中的作用，进行CRISPR/Cas9敲除技术以产生TGIF1沉默的前脂肪细胞。使用油红O染色,在3T3-F442A前脂肪细胞中不存在TGIF1消除了整个分化过程中的脂质积累。相反，我们在TGIF1沉默的3个T3-F442A前脂肪细胞中建立了3个稳定表达TGIF1和多西环素诱导的TGIF1的T3-F442A前脂肪细胞.值得注意的是,多西环素在初始分化阶段诱导TGIF1成功促进TGIF1沉默的3T3-F442A细胞的脂质积累。我们进一步探讨了TGIF1在早期分化中的作用机制。我们证明TGIF1通过上调CCAAT/增强子结合蛋白β表达促进有丝分裂克隆扩增，过氧化物酶体增殖物激活受体γ下游调节中断，并抑制p27kip1的表达。总之,我们加强了TGIF1在早期分化中的关键作用，这可能有助于解决肥胖相关的代谢综合征。
