Identification, biogenesis and function prediction of novel circRNA during the chicken ALV-J infection

Circular RNA (circRNA) is a new non-coding RNA with a highly conserved and stable covalently closed loop structure, and it plays an important role in a variety of biological processes and the occurrence of diseases. Based on the sequencing results, circRNA_3079 had the most significant difference between the infected group and normal group, up to about 8 times. It has attracted our attention and was selected for further verification and analysis. Though the characteristics analysis of circRNA_3079 in chicken, we found circRNA_3079 is a stable, circular transcript, which mainly exists in the cytoplasm. And it is widely expressed in various tissues of chickens, and highly expressed in lung, spleen, lymph and bursa of fabricius. Bioinformatics analysis results showed that circRNA_3079 and the predicted target genes are enriched in many pathways related to immunity or tumors, such as p53 signaling pathway, Jak-STAT signaling pathway and NOD-like receptor signaling pathway, which revealed that circRNA_3079 may indirectly regulate the ALV-J infection process through the regulation of target genes.HIGHLIGHTSCircRNA_3079 is an abundant and stable circular RNA expressed in different tissues and cells in chicken.The circularization of circRNA_3079 does not depend on the reverse complementary repetitive sequence of the flanking sequence.CircRNA_3079 may indirectly regulate the ALV-J infection process.