摘要
MicroRNAs(miRNAs)are a highly conserved class of small(18–24 nucleotides)non-coding RNAs that regulate a broad spectrum of biological processes.Aberrations or corruptions of miRNA functions may lead to deregulated cell proliferation,tumorigenesis,and ultimately,cancer.Increasing evidences suggested that a large fraction of miRNAs is regulated at the posttranscriptional stage,which impacts on the level and function of miRNAs during cell development and human diseases.Recently,several distinct mechanisms are emerging to regulate the biogenesis,stability and function of miRNAs at post-transcriptional level,such as specific binding to terminal loops of miRNA precursors(primiRNAs or pre-miRNAs)by RNA-binding proteins and 3’-terminal modifications by particular enzymes.Signaling cascades and post-translational modifications of the core components of RNA machinery also take part in the posttranscriptional regulation of miRNAs.
