Guo Chang-long, Liu Lei, Jia Yun-dan, Zhao Xiao-yang, Zhou Qi, Wang Liu
State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
Stem Cell Res. 2012 Sep;9(2):69-76. doi: 10.1016/j.scr.2012.04.004. Epub 2012 May 1.
OCT4 is a highly conserved gene and plays an important role during early embryonic development and differentiation. Similar to human OCT4, mouse Oct4 gene generates variants. Oct4A is a master regulator of self-renewal in pluripotent stem cells. In this study, we have identified a novel Oct4 spliced variant, designated mouse Oct4B, encoding 3 isoforms, termed Oct4B-247aa, Oct4B-190aa and Oct4B-164aa. Furthermore, we have examined the expression pattern of these isoforms in non-pluripotent cells and their function in somatic cell reprogramming. The results revealed the isoforms 247aa, 164aa localized mainly in nucleus and 190aa expressed dotted in the cytoplasm. In contrast to Oct4A, Oct4B does not function in somatic reprogramming as that of Oct4A. Taken together, our data for first time described the intact coding sequence of mouse Oct4B and its function in somatic cell reprogramming. These findings will be important for further analysis of the epigenetic mechanisms of reprogramming and highlight the necessity of discriminating Oct4 isoforms in future stem cell research.
OCT4是一个高度保守的基因，在早期胚胎发育和分化过程中发挥重要作用。与人类OCT4相似，小鼠Oct4基因会产生变体。Oct4A是多能干细胞自我更新的主要调节因子。在本研究中，我们鉴定出一种新的Oct4剪接变体，命名为小鼠Oct4B，它编码3种异构体，分别称为Oct4B-247aa、Oct4B-190aa和Oct4B-164aa。此外，我们检测了这些异构体在非多能细胞中的表达模式及其在体细胞重编程中的功能。结果显示，247aa和164aa异构体主要定位于细胞核，190aa异构体在细胞质中呈点状表达。与Oct4A不同，Oct4B在体细胞重编程中不起作用。综上所述，我们的数据首次描述了小鼠Oct4B的完整编码序列及其在体细胞重编程中的功能。这些发现对于进一步分析重编程的表观遗传机制具有重要意义，并凸显了在未来干细胞研究中区分Oct4异构体的必要性。
