Mos 3' UTR regulatory differences underlie species-specific temporal patterns of Mos mRNA cytoplasmic polyadenylation and translational recruitment during oocyte maturation.
The Mos proto-oncogene is a critical regulator of vertebrate oocyte maturation. The maturation-dependent translation of Mos protein correlates with the cytoplasmic polyadenylation of the maternal Mos mRNA. However, the precise temporal requirements for Mos protein function differ between oocytes of model mammalian species and oocytes of the frog Xenopus laevis. Despite the advances in model organisms, it is not known if the translation of the human Mos mRNA is also regulated by cytoplasmic polyadenylation or what regulatory elements may be involved. We report that the human Mos 3' untranslated region (3' UTR) contains a functional cytoplasmic polyadenylation element (CPE) and demonstrate that the endogenous Mos mRNA undergoes maturation-dependent cytoplasmic polyadenylation in human oocytes. The human Mos 3' UTR interacts with the human CPE-binding protein and exerts translational control on a reporter mRNA in the heterologous Xenopus oocyte system. Unlike the Xenopus Mos mRNA, which is translationally activated by an early acting Musashi/polyadenylation response element (PRE)-directed control mechanism, the translational activation of the human Mos 3' UTR is dependent on a late acting CPE-dependent process. Taken together, our findings suggest a fundamental difference in the 3' UTR regulatory mechanisms controlling the temporal induction of maternal Mos mRNA polyadenylation and translational activation during Xenopus and mammalian oocyte maturation.
Prasad
C Krishna
CK
Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
Mahadevan
Mahendran
M
MacNicol
Melanie C
MC
MacNicol
Angus M
AM
D020413:3' Untranslated Regions / Q000235:genetics*; D000818:Animals; D015153:Blotting, Western; D017931:DNA Primers / Q000235:genetics; D024202:Electrophoretic Mobility Shift Assay; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D016258:Genes, mos / Q000235:genetics*; D006801:Humans; D016297:Mutagenesis, Site-Directed; D009865:Oocytes / Q000254:growth & development* / Q000378:metabolism; D026723:Polyadenylation / Q000235:genetics*; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D013045:Species Specificity; D014157:Transcription Factors / Q000378:metabolism; D014981:Xenopus; D039221:mRNA Cleavage and Polyadenylation Factors / Q000378:metabolism
D020413:3' Untranslated Regions; C490386:CPEB1 protein, human; D017931:DNA Primers; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger; D014157:Transcription Factors; D039221:mRNA Cleavage and Polyadenylation Factors