Cdk6在维持ES细胞自我更新中的作用

细胞周期蛋白依赖性激酶6（cyclin dependent kinase 6，Cdk6）对胚胎早期发育有着重要的作用.然而，它在胚胎干（embryonic stem，ES）细胞中的生物学功能仍不清楚.在该研究中，我们运用RNA干扰技术和基因表达分析方法探索了Cdk6在小鼠胚胎干细胞中的功能及分子机制.结果表明：Cdk6的表达水平与小鼠ES细胞的自我更新密切相关.首先，维甲酸（RA）处理和白血病抑制因子（LIF）去除实验显示 ，随着ES细胞的分化，Cdk6的表达水平明显降低.更为重要的是，RNA干扰介导的Cdk6表达抑制导致ES细胞自我更新相关基因的显著下调，同时伴随细胞分化基因的表达激活，提示Cdk6对维持ES细胞自我更新至关重要.

The Role of Cdk6 in Maintaining the Self-renewal State of ES Cells

Cyclin-dependent kinase 6 (Cdk6) is an important factor in development, however, whether it is able to maintain the embryonic stem (ES) cells in undifferentiated state remained obscure. In this study, we investigated the function of Cdk6 in mouse ES cells by RNA interference and gene expression analyses. Our results showed that the expression level of Cdk6 was correlated with the self-renewal of the ES cells, with dramatic decrease upon retinoic acid (RA) treatment or leukaemia inhibitory factor (LIF) removal for the induction of ES cell differentiation. Cdk6 knockdown by RNA interference caused the ES cells into a undifferentiated state, where the expression of self-renewal genes were reduced and the expression of differentiation markers, such as Cdx2, were induced. Our findings suggested that an important function of Cdk6 was to maintain the mouse ES cells into a undifferentiated and self- renewing state.