Comparative analysis of the structural and expressional parameters of microRNA target genes

Insights into the miRNA regulations in human disease genes

BACKGROUND

MicroRNAs are a class of short non-coding RNAs derived from either cellular or viral transcripts that act post-transcriptionally to regulate mRNA stability and translation. In recent days, increasing numbers of miRNAs have been shown to be involved in the development and progression of a variety of diseases. We, therefore, intend to enumerate miRNA targets in several known disease classes to explore the degree of miRNA regulations on them which is unexplored till date.

RESULTS

Here, we noticed that miRNA hits in cancer genes are remarkably higher than other diseases in human. Our observation suggests that UTRs and the transcript length of cancer related genes have a significant contribution in higher susceptibility to miRNA regulation. Moreover, gene duplication, mRNA stability, AREScores and evolutionary rate were likely to have implications for more miRNA targeting on cancer genes. Consequently, the regression analysis have confirmed that the AREScores plays most important role in detecting miRNA targets on disease genes. Interestingly, we observed that epigenetic modifications like CpG methylation and histone modification are less effective than miRNA regulations in controlling the gene expression of cancer genes.

CONCLUSIONS

The intrinsic properties of cancer genes studied here, for higher miRNA targeting will enhance the knowledge on cancer gene regulation.

Complex-forming proteins escape the robust regulations of miRNA in human

Most proteins carry out their functions by participating in protein complexes. Recently, miRNAs were identified as promising post-transcriptional regulators that influence a large proportion of genes in higher eukaryotes. We aim to understand the role of miRNAs in the regulation of human proteins that are present in protein complexes. Here, we show that robust regulation by miRNA is absent in human complex-forming proteins. Moreover, the numbers of miRNA hits cannot direct the evolutionary fate of complex-forming proteins independently. However, the duplicated complex-forming proteins having a severe effect on organismal fitness are profoundly targeted by miRNA, probably to reduce the chances of dosage imbalance.