Sequence-specific RNA-binding protein that regulates mRNA cytoplasmic polyadenylation and translation initiation during oocyte maturation and early development. Binds to the cytoplasmic polyadenylation element (CPE), an uridine-rich sequence element (consensus sequence 5'-UUUUUAU-3') within the mRNA 3'-UTR (By similarity). Microtubule-associated. Expressed in oocytes (at protein level). During oocyte maturation becomes detectable at stage Ib, and remains ubiquitously distributed within the oocyte cytoplasm until stage II. It then follows a gradual accumulation to the future animal pole during stage III, and remains localized to this pole at stage IV (at protein level). Expressed in oocytes, blastomeres and pre-mid-blastula transition embryos. Its expression during oogenesis is ubiquitous at stages I and II, but gradually accumulated at the periphery of the oocyte in the presumptive animal pole during stage III. Expression was maintained in that region at stage IV, and then became delocalized at stage V to cover a much broader area presumably encompassing the future blastodisc. Belongs to the RRM CPEB family.