MEIOC (meiosis specific with coiled-coil domain) is an RNA-binding protein essential for meiosis completion in both male and female germ cells. Its primary function is to stabilize meiotic mRNAs while simultaneously destabilizing mitotic transcripts, enabling the critical transition from mitotic to meiotic cell cycle programs 1. MEIOC operates as part of a posttranscriptional regulatory complex with RNA helicase YTHDC2 and RNA-binding protein RBM46, which together target mitotic genes like E2f6 and Mga for degradation 23. This mRNA decay mechanism derepresses meiosis-associated genes, including Meiosin, thereby conferring molecular competence for meiotic entry 3. In oogenesis, MEIOC additionally prevents continued mitotic cycling by downregulating the G1/S cyclin CCNA2, while promoting entry into meiosis via the STRA8-MEIOSIN pathway 4. Importantly, MEIOC's function operates independently of retinoic acid signaling, suggesting it represents an ancestral posttranscriptional mechanism complementing transcriptional regulation 1. Dysfunction of MEIOC or its binding partners causes early meiotic defects and infertility in mice, with dysregulated expression associated with human male fertility disorders 2. MEIOC overexpression promotes meiotic initiation from human pluripotent stem cells, indicating therapeutic potential for infertility treatment 56.