Identifying And Profiling The Micrornas Associated With Skin Colour In The Muchuan Black-Bone Chicken

MicroRNAs (miRNAs) are an abundant class of small non-protein-coding RNAs that regulate gene expression in plants and animals. Skin colour is an important economic consideration in chicken production, and chickens with black skin have high market value. Nevertheless, little research has been conducted on miRNA regulation of melanogenesis in chicken skin. In this study, we sampled the dorsal skins of chickens with black (BS) and white (WS) skin to construct six small RNA libraries. High-throughput sequencing technology was then used to identify which miRNAs were expressed differentially between the BS and WS phenotypes. A total of 645 known and 64 novel miRNAs were identified from the six sequencing libraries. Additionally, the expression of 18 miRNAs was significantly different between the two phenotypes, including 9 miRNAs that were up-regulated, and 9 that were down-regulated. We identified 2 miRNAs, i.e. miR-204 and miR-6631-5p, that may be important for melanogenesis in chicken skin. Our data contribute to the understanding of the molecular mechanism, through miRNA regulation, of melanin formation in chicken skin.