Characterization of circRNA expression profiles associated with non-Mendelian inheritance in feather growth of chickens

Non-coding RNAs such as miRNAs play a crucial role in chicken feather growth rate. However, circular RNA (circRNA) expression profiles in fast- and slow feathered chickens that follow and do not follow Mendelian inheritance are unclear. RNA sequencing was used to analyze circRNA expression profiles in hair follicles of slow feathered chickens that follow genetic rules and fast-feathered chickens that did not follow genetic rules. Differentially expressed circRNAs-miRNA-mRNA competing endogenous RNAs (ceRNA) network were then constructed. Finally, the key factors and regulation mechanisms controlling feather rate were identified.Our results revealed that 67 circRNAs were differentially expressed in hens, including 22 up-regulated and 45 down-regulated circRNAs in non-Mendelian inheritance-mediated fast-feathering hens compared with Mendelian inheritance-mediated slow-feathering hens. In addition, 16 differentially expressed circRNAs were identified in cocks, including 9 up-regulated and 7 down-regulated circRNAs in non-Mendelian inheritance-mediated fast-feathering cocks compared with Mendelian inheritance-mediated slow-feathering cocks. Moreover, circRNA-mediated ceRNA regulation of hair follicle formation was particularly abundant in the Jak-STAT signaling pathway, Wnt signal pathway, and Toll-like receptor signaling pathway. Furthermore, circABI3BP was seen to be a crucial circRNA in regulating feather growth rate, by binding with gga-miR-1649-5p to regulate SSTR2 expression. In conclusion, this study analyzed circRNA expression profiles in fast- and slow feathered chickens that follow and do not follow Mendelian inheritance, which laid the foundation for understanding the role of circRNA in chicken feather growth rate.