Novel circRNAs from cashmere goats: Discovery, integrated regulatory network, and their putative roles in the regeneration and growth of secondary hair follicles

Abstract

Circular RNAs (circRNAs) were identified as noncoding RNAs with covalently closed structures differing from other types of RNA molecules. It was thought that circRNAs were implicated in the development of secondary hair follicles (SHFs) of cashmere goats. In this investigation, a total of 21 novel circRNAs were identified from the skin tissue of cashmere goats. Of them, nine circRNAs were found to be significantly higher in expression at anagen skin tissue than those at telogen of cashmere goats. Based on bioinformatics analysis, a complicated regulatory relationship was revealed among the nine upregulated circRNAs at anagen with related signalling pathways, such as Wnt signalling pathway, TGF-beta signalling pathway, mTOR signalling pathway, MAPK signalling pathway, and axon guidance. Further, the expression pattern analysis of the nine upregulated circRNAs at anagen along with their host genes in SHFs suggested their potential functional roles in the regeneration and growth of anagen SHFs of cashmere goats. Our results provided novel significant information for elucidating the molecular regulatory mechanisms understanding the regeneration and growth of SHFs in cashmere goats, which will be essential for artificially regulating the growth of cashmere to increase cashmere yield.