Comprehensive circ RNA expression profile and construction of circ RNA ‐associated ce RNA network in fur skin

Circular RNA (circ RNA ), a class of non‐coding RNA s, is a new group of RNA s that are related to tumorigenesis. The role of circ RNA s in various diseases has been already highlighted. However, the expression levels and functions of circ RNA s related to the melanocytes in the skin are poorly understood. RNA sequence was performed to analyse the expression profiles of circ RNA s in black fur skin and white fur skin during different differentiation stages and investigate the relevant metabolism mechanisms. Differentially expressed circ RNA s were detected using empirical Bayes sequencing ( EBS eq) and then verified through the quantitative real‐time PCR method. The EQS eq analysis of circ RNA s identified 11 downregulated and 32 upregulated circ RNA s in the embryo of black fur skin and white fur skin, as well as 21 downregulated and 17 upregulated circ RNA in the postnatal stage. A circ RNA –micro RNA (mi RNA )–messenger RNA ( mRNA ) network was established to predict the circ RNA targets. Gene ontology ( GO ) analysis and Kyoto Encyclopedia of Genes and Genomes ( KEGG ) pathway analysis were applied to enrich the mRNA data further. Results showed that the specific mRNA s mainly involved in the transcription‐related GO s, especially GO :0042802, GO :0005080 and GO :0032403, demonstrate their specific actions in transcriptional regulation. In the circ RNA –mi RNA – mRNA network, the most enriched GO terms of the mRNA s were pigmentation, protein autophosphorylation and protein complex. Therefore, the circ RNA –mi RNA – mRNA pathway may reveal novel mechanisms for pigmentation, and circ RNA s may serve as candidates in pigmentation.