Cytoplasmic Polyadenylation Element Binding Protein 4 (CPEB4)

The deduced 712-amino acid protein shares significant identity with mouse Cpeb1. RT-PCR ELISA detected intermediate to high expression of CPEB4 in all tissues examined, with highest levels in brain, kidney, heart, and fetal liver. CPEB4 was expressed in all specific adult brain regions examined, with highest levels in cerebellum, spinal cord, caudate nucleus, hippocampus, and substantia nigra.

CPEB, or cytoplasmic polyadenylation element binding protein, is a highly conserved RNA-binding protein that promotes the elongation of the polyadenine tail of messenger RNA. CPEB most commonly activates the target RNA for translation, but can also act as a repressor, dependent on its phosphorylation state.