High expression circRALGPS2 in atretic follicle induces chicken granulosa cell apoptosis and autophagy via encoding a new protein

The reproductive performance of chickens mainly depends on the development of follicles. Abnormal follicle development can lead to decreased reproductive performance and even ovarian disease among chickens. Chicken is the only non-human animal with a high incidence of spontaneous ovarian cancer. In recent years, the involvement of circRNAs in follicle development and atresia regulation has been confirmed.

In the present study, we used healthy and atretic chicken follicles for circRNA RNC-seq. The results showed differential expression of circRALGPS2. It was then confirmed that circRALGPS2 can translate into a protein, named circRALGPS2-212aa, which has IRES activity. Next, we found that circRALGPS2-212aa promotes apoptosis and autophagy in chicken granulosa cells by forming a complex with PARP1 and HMGB1.

Our results revealed that circRALGPS2 can regulate chicken granulosa cell apoptosis and autophagy through the circRALGPS2-212aa/PARP1/HMGB1 axis.