Send to

Choose Destination
Mol Cell. 2000 Nov;6(5):1253-9.

Phosphorylation of CPEB by Eg2 mediates the recruitment of CPSF into an active cytoplasmic polyadenylation complex.

Author information

Department of Molecular Genetics and Microbiology University of Massachusetts Medical School, Worcester, MA 01655, USA.


The release of Xenopus oocytes from prophase I arrest is largely driven by the cytoplasmic polyadenylation-induced translation of dormant maternal mRNAs. Two cis elements, the CPE and the hexanucleotide AAUAAA, and their respective binding factors, CPEB and a cytoplasmic form of CPSF, control polyadenylation. The most proximal stimulus for polyadenylation is Eg2-catalyzed phosphorylation of CPEB serine 174. Here, we show that this phosphorylation event stimulates an interaction between CPEB and CPSF. This interaction is direct, does not require RNA tethering, and occurs through the 160 kDa subunit of CPSF. Eg2-stimulated and CPE-dependent polyadenylation is reconstituted in vitro using purified components. These results demonstrate that the molecular function of Eg2-phosphorylated CPEB is to recruit CPSF into an active cytoplasmic polyadenylation complex.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center