The regulated translation of messenger RNA is essential for cell-cycle progression,
establishment of the body plan during early development and modulation
of key activities in the central nervous system. Cytoplasmic polyadenylation,
one mechanism of controlling translation, is driven by cytoplasmic
polyadenylation element binding protein, CPEB. CPEB is a highly conserved,
sequence-specific RNA-binding protein that binds to the cytoplasmic
polyadenylation element, thereby modulating translational repression and
mRNA localization. Blocking cytoplasmic polyadenylation by interfering with
the CPE or CPEB prevents the translational activation and translational
repression of mRNAs crucial for oocyte maturation. CPEB is synthesized during
oogenesis and stockpiled in the oocyte. CPEB degradation occurs via the
proteasome pathway, most likely through ubiquitin-conjugated intermediates.