细胞周期中MicroRNA的调控作用

MicroRNA是近年来发现并热点研究的一类重要的非编码RNA，在干细胞的更新与分化、体细胞性状与数量的维持、甚至肿瘤细胞的恶性增生等生物学过程中都具有重要的调控作用.microRNA通过与靶位点结合而快速有效地降解靶基因mRNA或抑制蛋白的翻译，下调E2F、CDK、cyclin、p21、p27、DNA多聚酶α等关键的细胞周期调控因子的表达，加速或减慢细胞增殖的速度.microRNA对细胞周期的调控还将涉及到微生物感染机体的过程、免疫系统的调控、妊娠期母体的变化、组织的修复、细胞的凋亡与衰老等诸多方面.随着对microRNA调控细胞周期机制的深入研究，microRNA及其靶基因不仅可以作为某些疾病的分子标记物，而且可以用于指导疾病的预防和治疗.

Regulation of Cell Cycle by MicroRNAs

The precise regulation of cell cycles is criticle for cells in various biological aspects, such as stem cell renewal, differentiation, phenotype maintenance and even tumorgenicity. As a rapid and potent mechanism to downregulate protein translations, microRNAs are significantly involved in the cell cycle progression by targeting numerous key regulators of cell cycle, such as CDKs, cyclins, p21, p27,DNA pol α etc. Under certain circumstances, the biological impacts mediated by microRNAs can be either individually or integrately. For instance, miR-206 is essential for both differentiation and cell cycle arrest during myogenesis. The regulation cell cycles by microRNAs appeared to be influenced by many biological processes, like apoptosis, senescence, viral infections, host immune response, tissue repairing or even pregnancy. MicroRNAs and their target genes could be used as biological markers for clinical diagnosis, and provide potential therapeutic strategies to certain diseases, such as cancer and stem cell deficiency.