Fujii Yoichi R
Retroviral Genetics Group, Nagoya City University, Nagoya, 467-8603, Japan.
Open Virol J. 2010 May 25;4:63-75. doi: 10.2174/1874357901004010063.
Embryonic stem cells (ESCs) are capable of undergoing self-renewal, and their developmental ability is known as the stemness. Recently, microRNAs (miRNAs) as regulators have been isolated from ESCs. Although Dicer and DiGeorge syndrome critical region gene 8 (DGCR8) are essential factors for the biogeneration of miRNA, Dicer-knockout (KO) ESCs have showed to fail to express differentiation markers and DGCR8-KO ESCs have showed to be arrest in the G1 phase. Furthermore, Dicer-KO ESCs lost the ability to epigenetically silence retroelemtns (REs). REs are expressed and transposed in ESCs, whose transcripts control expression of miRNAs, and their transposable retroelement (TE) expression is, therefore related to ESC proliferation and differentiation, suggesting that the interplay between miRNAs and REs may have a deep responsibility for the stemness including a short G1/S transition and for RE regulation in ESCs.
胚胎干细胞（ESCs）能够进行自我更新，其发育能力被称为干性。最近，作为调节因子的微小RNA（miRNAs）已从ESCs中分离出来。尽管Dicer和22q11.2微缺失综合征关键区域基因8（DGCR8）是miRNA生物生成的关键因子，但Dicer基因敲除（KO）的ESCs已显示无法表达分化标志物，而DGCR8基因敲除的ESCs已显示停滞在G1期。此外，Dicer基因敲除的ESCs失去了对逆转录元件（REs）进行表观遗传沉默的能力。REs在ESCs中表达并转座，其转录本控制miRNAs的表达，因此它们的转座子逆转录元件（TE）表达与ESCs的增殖和分化相关，这表明miRNAs与REs之间的相互作用可能对包括短G1/S转换在内的干性以及ESCs中的RE调控负有重大责任。
