Required to establish and maintain the arrest of oocytes at the second meiotic metaphase until fertilization. Acts by inhibiting the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase. Probably recognizes and binds to some phosphorylated proteins and promotes their ubiquitination and degradation (PubMed:34052850, PubMed:34595750). Plays a vital role in modulating the ubiquitilation of CCNB1 and CDK1 during gametogenesis. {ECO:0000250|UniProtKB:Q8CDI2, ECO:0000269|PubMed:34052850, ECO:0000269|PubMed:34595750}. This is the function of FBXO43 (F-box protein 43, ENSG00000156509).