Experimental confirmation of predicted microRNA in seventh intron of E-Cadherin gene

E-cadherin is a transmembrane glycoprotein that found at adherens junctions (1, 2). The E-Cadherin gene which is located at chromosome 16q22.1, is a common hotspot of genetic mutations. E-cadherin has been reported to be down regulated in some types of cancers (3-5). Some recent studies have shown that some microRNAs (miRNA) located at the gene would have regulatory effects on their host gene (6). So far about 2500 human miRNAs have been recorded in mirbase databank (http://www.mirbase.org/index.shtml) while this amount has changed to 55000 by bioinformatics studies (7). In the past, for detection of new miRNAs, cloning and sequencing have been used but these methods have several inefficiency because of the small size of miRNAs and their redundancy(8, 9). In this regards, novel miRNAs can be predicted by bioinformatics tools and then should be confirmed by experimental tools. So we selected one of the bioinformatically predicted miRNA in E-Cadherin gene located at seventh intron of the gene. Then we evaluated the existence of the predicted miRNA by wet lab studies. A DNA segment corresponding to the predicted miRNA sequence was transfected in HEK293t cell line. The expression of the mature miRNA was evaluated by RT-PCR. The result of RT-PCR proved the expression of approximately 80 bp mature miRNA. Further studies are required to find the function, target genes and regulatory effects of this mature miRNA.

Keywords:

Putative microRNA , E-Cadherin , Bioinformatics tools