RNA binding protein SERBP1 is indispensable for oocyte development and maturation in mice.

RNA-binding proteins (RBPs) are critical regulators of post-transcriptional gene expression and RNA processing during mammalian oocyte development. SERPINE1 mRNA-binding protein 1 (SERBP1), a conserved RNA-binding protein (RBP), exhibits prominent expression in the female reproductive system and throughout oogenesis. Conditional deletion of Serbp1 using oocyte-specific Zp3⁠/⁠Gdf9⁠-Cre drivers resulted in arrested oocyte growth, female infertility, and failure of blastocyst formation from two-cell embryos. Phenotypic analysis revealed spindle assembly defects, impaired asymmetric division, and compromised meiotic competence in oocytes. Notably, Serbp1 ablation also induced granulosa cell apoptosis and elevated Erk1/2 phosphorylation levels, indicating dysregulation of somatic microenvironment. Furthermore, conditional knockout mice exhibited prolonged diestrus cycles. Collectively, these findings demonstrate that SERBP1 coordinates essential RNA-regulatory functions for oocyte developmental competence through both cell-autonomous mechanisms and somatic-germline crosstalk.