miR-isomiRExp: a web-server for the analysis of expression of miRNA at the miRNA/isomiR levels

MicroRNA (miRNA) locus has been found that can generate a series of varied isomiR sequences. Most studies always focus on determining miRNA level, however, the canonical miRNA sequence is only a specific member in the multiple isomiRs. Some studies have shown that isomiR sequences play versatile roles in biological progress, and the analysis and research should be simultaneously performed at the miRNA/isomiR levels. Based on the biological characteristics of miRNA and isomiR, we developed miR-isomiRExp to analyze expression pattern of miRNA at the miRNA/isomiR levels, provide insights into tracking miRNA/isomiR maturation and processing mechanisms, and reveal functional characteristics of miRNA/isomiR. Simultaneously, we also performed expression analysis of specific human diseases using public small RNA sequencing datasets based on the analysis platform, which may help in surveying the potential deregulated miRNA/isomiR expression profiles, especially sequence and function-related isomiRs for further interaction analysis and study. The miR-isomiRExp platform provides miRNA/isomiR expression patterns and more information to study deregulated miRNA loci and detailed isomiR sequences. This comprehensive analysis will enrich experimental miRNA studies. miR-isomiRExp is available at http://server.malab.cn/miRisomiRExp/.