Our knowledge of gene regulators presents an intrinsically unbalanced picture inadequate to fully explain the great complexity of their cellular functions. It is now understood that gene regulation assumes multiple modes including transcriptional regulation by transcription factors (TFs) and the posttranscriptional regulation by microRNA (miRNA). MiRNA is a class of small noncoding RNAs of ,22 nucleotides. It is known to repress transcription and/or inhibit translation of a large number of genes by binding mainly to the 3r untranslated region (UTR) of target genes [1], [2]. Elucidating specific functions of miRNAs comprises one of the most active research areas. ©2012 IEEE.