Study On The Inhibitory Mechanisms Of Human Erythroleukemia K562 Cells Induced By MiR-181a

MicroRNAs (miRNAs) are a class of genome-encoded small, single-stranded RNAs which range in size from 19 to 25 nucleotides (nt) and are typically excised from a 60 to 110 nt hairpin (fold-back) RNA (named pre-microRNA) structure that is transcribed from a larger primary transcript (named pri-microRNA). miRNAs always function as negative regulators of gene expression, and play crucial roles in diverse developmental and physiological events which have been demonstrated in the last few years. They are thought to elicit mRNA degradation (if they bind in perfect complementarity to the target mRNA) or to arrest mRNA translation (if binding is imperfect). However, in animals, miRNAs bind imperfectly to the 3' UTR sequences of mRNA and attenuate protein translation by unknown mechanisms. In all known cases microRNAs repress expression of protein-coding target genes, either by repressing translation while not affecting the mRNA concentration of the target, or potentially by directly inducing a decrease in target mRNA concentrations.To data, a large number of miRNAs have been identified in human, and some of...