A Network of Circular RNA and MicroRNA Sequencing Provides Insights into Pigment Deposition of Changshun Blue Eggshell Chickens.

Eggshell color plays important biological roles and attracts the attention of both egg retailers and researchers. However, whether non-coding RNAs are involved in pigment deposition among different eggshell colors remains unknown. In this study, RNA sequencing was used to analyse the uterine gland transcriptome (CircRNA and miRNA) of Changshun chicken blue-shell hens producing four different eggshell color eggs including dark blue PK(DB) and light blue (LB), dark brown and greenish (between blue and pink, DP) and pink (p). We found that , targeting , was expressed in DB, DP, and LB groups compared with the PK group, which indicates that may play a role in the blue eggshell color. KEGG and GO analyses showed that the "metabolic pathways" with targeted genes such and were detected in dark and light blue color eggshell chickens, which confirms the different ratios of biliverdin and involved in the deposition of blue color. As annotated by connectivity analysis, and , belonging to the family, are involved in the signaling pathway, which plays an important role in cell growth, differentiation, metastasis and apoptosis. Our findings enrich the database of circRNA, miRNAs and genes for chicken uterine tissue, which will be useful in accelerating molecular selection for blue eggshell color layers.