Identification of MicroRNAs Targeting to a Specific mRNA Loci

Purification of human mRNAs encoding cyclin-dependent kinase inhibitor 1A (CDKN1A), also known as p21Cip1/Waf1 and signal transducer and activator of transcription 3 (STAT3) identified many miRNAs using multiplex miRNA array in HepG2 and PC-3 cells. To investigate the miRNAs targeting to one specific gene in vivo, we developed a protocol miRIP to affinity purify the miRNAs from an endogenous segment of mRNA using nucleic acid hybridization and use multiplex miRNA array to identify the associated miRNAs.