A novel mRNA 3' untranslated region translational control sequence regulates Xenopus Wee1 mRNA translation.
Cell cycle progression during oocyte maturation requires the strict temporal regulation of maternal mRNA translation. The intrinsic basis of this temporal control has not been fully elucidated but appears to involve distinct mRNA 3' UTR regulatory elements. In this study, we identify a novel translational control sequence (TCS) that exerts repression of target mRNAs in immature oocytes of the frog, Xenopus laevis, and can direct early cytoplasmic polyadenylation and translational activation during oocyte maturation. The TCS is functionally distinct from the previously characterized Musashi/polyadenylation response element (PRE) and the cytoplasmic polyadenylation element (CPE). We report that TCS elements exert translational repression in both the Wee1 mRNA 3' UTR and the pericentriolar material-1 (Pcm-1) mRNA 3' UTR in immature oocytes. During oocyte maturation, TCS function directs the early translational activation of the Pcm-1 mRNA. By contrast, we demonstrate that CPE sequences flanking the TCS elements in the Wee1 3' UTR suppress the ability of the TCS to direct early translational activation. Our results indicate that a functional hierarchy exists between these distinct 3' UTR regulatory elements to control the timing of maternal mRNA translational activation during oocyte maturation.
Wang
Yi Ying
YY
Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Slot 814, 4301 W. Markham St., Little Rock, AR 72205, USA.
Charlesworth
Amanda
A
Byrd
Shannon M
SM
Gregerson
Robert
R
MacNicol
Melanie C
MC
MacNicol
Angus M
AM
D020413:3' Untranslated Regions / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000235:genetics*; D017931:DNA Primers / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics*; D009865:Oocytes / Q000254:growth & development / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D038621:Regulatory Sequences, Ribonucleic Acid / Q000235:genetics; D017422:Sequence Analysis, DNA; D014981:Xenopus / Q000235:genetics / Q000502:physiology*; D029867:Xenopus Proteins / Q000235:genetics*
D020413:3' Untranslated Regions; D018797:Cell Cycle Proteins; D017931:DNA Primers; D009687:Nuclear Proteins; D038621:Regulatory Sequences, Ribonucleic Acid; D029867:Xenopus Proteins; C530005:WEE1 protein, Xenopus; D011505:Protein-Tyrosine Kinases