Nearly two decades ago, Xenopus oocytes were found to contain mRNAs harboring a 
small sequence in their 3' untranslated regions that control cytoplasmic 
polyadenylation and translational activation during development. This 
cytoplasmic polyadenylation element (CPE) is the binding platform for 
CPE-binding protein (CPEB), which promotes polyadenylation-induced translation. 
Since then, the biochemistry and biology of CPEB has grown rather substantially: 
mechanistically, CPEB nucleates a complex of factors that regulates poly(A) 
elongation through, of all things, a deadenylating enzyme; biologically, CPEB 
mediates many processes including germ-cell development, cell division and 
cellular senescence, and synaptic plasticity and learning and memory. These 
observations underscore the growing complexities of CPEB involvement in cell 
function.