Hishida Tomoaki, Naito Kumiko, Osada Shigehiro, Nishizuka Makoto, Imagawa Masayoshi
Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, Aichi 467-8603, Japan.
Biochem Biophys Res Commun. 2008 May 30;370(2):289-94. doi: 10.1016/j.bbrc.2008.03.091. Epub 2008 Mar 27.
Cyclin D2 was isolated as one of the genes expressed early in adipogenesis. The expression of cyclin D2 increased temporarily early on and then again late in the differentiation process. The expression of cyclin D1 and cyclin D3, the other D-type cyclins, was also transiently induced early during adipocyte differentiation. RNAi (RNA interference)-mediated knockdown of cyclin D1, D2, or D3 inhibited the differentiation of 3T3-L1 cells into lipid-laden adipocytes. Moreover, the knockdown of cyclin D1 or D3 significantly inhibited mitotic clonal expansion (MCE), while silencing of the cyclin D2 gene had a milder effect on MCE. Each of the D-type cyclins seems to play a crucial role in adipocyte differentiation by regulating MCE.
细胞周期蛋白D2是作为脂肪生成早期表达的基因之一被分离出来的。细胞周期蛋白D2的表达在早期暂时增加，然后在分化过程后期再次增加。其他D型细胞周期蛋白，即细胞周期蛋白D1和细胞周期蛋白D3的表达，在脂肪细胞分化早期也被短暂诱导。RNA干扰（RNAi）介导的细胞周期蛋白D1、D2或D3的敲低抑制了3T3-L1细胞向富含脂质的脂肪细胞的分化。此外，细胞周期蛋白D1或D3的敲低显著抑制有丝分裂克隆扩增（MCE），而细胞周期蛋白D2基因的沉默对MCE的影响较小。每种D型细胞周期蛋白似乎都通过调节MCE在脂肪细胞分化中发挥关键作用。
