Mammalian miRNA curation through next-generation

Characteristic small RNA biogenesis processing patterns are used for the discovery ofnovel microRNAs (miRNAs) from next-generation sequencing data. Here, we highlightand discuss key criteria for mammalian – specifically human – miRNA database curationbased on small RNA sequencing data. Sequence reads obtained from small RNA cDNAlibraries are aligned to reference genomic regions, and miRNA genes are revealed bytheir distinct read length and bimodal read frequency distribution, the predicted secondarystructure of the deduced miRNA stem-loop precursor molecule, and, to a lesser degree,basedonevolutionaryconservationofsmallRNAsfromothervertebrates.ProperlycuratedmiRNA databases are an important resource for investigators interested in miRNA biology,diagnostics, and therapeutics.