Maskin Is a CPEB-Associated Factor that Transiently Interacts with eIF-4E

• Published in: Molecular cell Vol. 4; no. 6; pp. 1017 - 1027
• Main Authors: Stebbins-Boaz, Barbara, Cao, Quiping, de Moor, Cornelia H, Mendez, Raul, Richter, Joel D
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01-12-1999
• ISSN: 1097-2765; 1097-4164
• DOI: 10.1016/S1097-2765(00)80230-0

In
Xenopus, the CPE is a bifunctional 3′ UTR sequence that maintains maternal mRNA in a dormant state in oocytes and activates polyadenylation-induced translation during oocyte maturation. Here, we report that CPEB, which binds the CPE and stimulates polyadenylation, interacts with a new factor we term maskin. Maskin contains a peptide sequence that is conserved among eIF-4E-binding proteins. Affinity chromatography demonstrates that CPEB, maskin, and eIF-4E reside in a complex in oocytes, and yeast two-hybrid analyses indicate that CPEB and maskin bind directly, as do maskin and eIF-4E. While CPEB and maskin remain together during oocyte maturation, the maskin-eIF-4E interaction is substantially reduced. The dissolution of this complex may result in the binding of eIF-4E to eIF-4G and the translational activation of CPE-containing mRNAs.