Maskin is a CPEB-associated factor that transiently interacts with elF-4E.
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 elF-4E-binding proteins. Affinity chromatography demonstrates that CPEB, maskin, and elF-4E reside in a complex in oocytes, and yeast two-hybrid analyses indicate that CPEB and maskin bind directly, as do maskin and elF-4E. While CPEB and maskin remain together during oocyte maturation, the maskin-elF-4E interaction is substantially reduced. The dissolution of this complex may result in the binding of elF-4E to elF-4G and the translational activation of CPE-containing mRNAs.
Stebbins-Boaz
B
B
Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester 01655, USA.
Cao
Q
Q
de Moor
C H
CH
Mendez
R
R
Richter
J D
JD
D020413:3' Untranslated Regions / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D039561:Eukaryotic Initiation Factor-4E; D005260:Female; D008969:Molecular Sequence Data; D009865:Oocytes; D010448:Peptide Initiation Factors / Q000235:genetics*; D014176:Protein Biosynthesis; D016601:RNA-Binding Proteins / Q000235:genetics*; D016415:Sequence Alignment; D014157:Transcription Factors / Q000235:genetics*; D014981:Xenopus / Q000235:genetics*; D029867:Xenopus Proteins; D039221:mRNA Cleavage and Polyadenylation Factors
D020413:3' Untranslated Regions; C490388:Cpeb1 protein, Xenopus; D039561:Eukaryotic Initiation Factor-4E; D010448:Peptide Initiation Factors; D016601:RNA-Binding Proteins; D014157:Transcription Factors; D029867:Xenopus Proteins; D039221:mRNA Cleavage and Polyadenylation Factors