title: Substrate-specific regulation of RNA deadenylation in Xenopus embryo and activated egg extracts.
abstract: The poly(A) tail of mRNAs plays an important role in translational control. In Xenopus laevis matured oocytes, maternal mRNAs that contain a cytoplasmic polyadenylation element (CPE) are polyadenylated, whereas CPE deficient mRNAs are deadenylated by a default process. Eg mRNAs are maternal transcripts that are poly(A)+ in matured oocytes and rapidly deadenylated after fertilization. This post-fertilization deadenylation of Eg mRNAs requires specific sequence information. Such a deadenylation element has been identified previously in the 3'UTR of Eg2 mRNA. In this study, we show that cell-free extracts made from embryos or activated eggs contain two kinetically distinct deadenylation activities, with different substrate specificities. One, responsible for the slow deadenylation of RNAs that are devoid of a functional CPE, has the characteristics of a default PAN activity. The other effectuates the rapid deadenylation of RNAs containing a deadenylation element. The in vitro system described here will allow the characterization of factors controlling the deadenylation of Eg mRNAs in embryos.
authors.affiliation: Departement de Biologie et Génétique du Développement, CNRS URA 256, Université de Rennes I, France. vincent.legagneux@univ-rennes1.fr
authors.forename: V
authors.initials: V
authors.lastname: Legagneux
authors.forename: F
authors.initials: F
authors.lastname: Omilli
authors.forename: H B
authors.initials: HB
authors.lastname: Osborne
mesh_terms: D000818:Animals; D001483:Base Sequence; D002474:Cell-Free System; D002678:Chimera / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000378:metabolism; D005095:Exoribonucleases / Q000378:metabolism; D005260:Female; D066298:In Vitro Techniques; D007700:Kinetics; D008969:Molecular Sequence Data; D009865:Oocytes / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D011061:Poly A / Q000235:genetics / Q000378:metabolism; D014176:Protein Biosynthesis; D012313:RNA / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity; D014982:Xenopus laevis
chemical_list: D018076:DNA, Complementary; D005095:Exoribonucleases; D011061:Poly A; D012313:RNA