Profiling of plasma microRNA expression in horses (Equus caballus) using next‐generation sequencing (1050.7)

Abstract

A microRNA (miRNA) is a small non‐coding RNA molecule, which functions in transcriptional and post‐transcriptional regulation of gene expression. It has been reported that the expression of miRNAs is associated with the incidence of various diseases in mammalian animals and may be used for the diagnostic purposes. In this study, we are determining the expression profile of miRNAs in horse plasma using next generation sequencing techniques, as an initial step to develop diagnostic markers for various diseases. We have identified 1032 miRNA species in plasma samples of three healthy thoroughbred horses (Equus caballus), accounting for 50% of the total small RNA population. The miRNA genes are dispersed throughout all the chromosomes. Among the identified miRNAs, 272 species have been previously reported in horses and other animals, while 760 species are novel species. Only 411 species, about 40% of miRNA identified, were expressed commonly in the three plasma samples, demonstrating wide inter‐individual variation in plasma miRNA expression. We are currently analyzing plasma miRNA expression in horses suffering various diseases in order to indentify the disease‐specific expression pattern of miRNAs.