microRNAs (miRNAs) are small,evolutionarily conserved,endogenous and noncod- ing RNA molecules of about 22 nuleotides in length that function as post- transcriptional gene regulators. MiRNAs inhibit the expression of target genes by affecting the translation or stability of target miRNA by binding to a target site in the 3’-UTR of target mRNAs. Researches indicate that miRNAs are involved in various biological processes,including development,differentiation,cell proliferation and its death. Accumulating evi...