BCAS2 regulates alternative splicing during mouse oocyte development

In this study, the mouse model of oocyte specific deletion of Bcas2 was generated using Vasa-Cre. Our results showed that Vasa-Cre mediated deletion of Bcas2 causes poor oocyte quality, impaired meiotic competence, abnormal follicle development and female infertility eventually. Single-cell RNA sequencing showed that 1334 genes are differentially expressed between control and Bcas2f/-;V-Cre oocytes, among which some down-regulated genes are associated with oogenesis and folliculogenesis. Furthermore, alternative splicing (AS) analysis showed that depletion of Bcas2 causes alteration of 991 AS events that involves 706 genes, among which are Dazl, Pabpc1l, Nobox, Zfp207, Mybl2, Prc1, Spc25 that are associated with oogenesis and spindle assembly. Taken together, our data not only corroborates the critical role of Bcas2 in oogenesis/folliculogenesis and determining oocyte quality, but also possibly provides a new molecular target for clinical research on the prevention and treatment of female infertility and other related reproductive diseases.