qRT-PCR analysis of circRNA expression. (A) Agarose gel electrophoresis of primers used to amplify circRNAs. (B) Sanger sequencing confirmation of the backsplicing junction of circRNAs. (C) RT-qPCR validation of different DE circRNAs in GCs of SYFs. a, b, c, d, and e represent circRNAs circRNA_1946, circRNA_0320, circRNA_0185, circRNA_0007, and circRNA_1481, respectively. Abbreviations: circRNAs, circular RNAs; GCs, granulosa cells