Clast4, the murine homologue of human eIF4E-Transporter, is highly expressed in developing oocytes and post-translationally modified at meiotic maturation.
In metazoans, translational regulation of a set of maternal mRNAs directs oocyte maturation and early embryogenesis. These transcripts are often kept dormant until their products are spatially and temporally required in development. The interaction between general translation factors (i.e. eIF4E) and their specific interactors influences translation initiation. A search of the protein database for a mouse homologue of the Drosophila Cup protein, a translational repressor during female germ-line development, identified the product of the Clast4 gene. In this report, we show that Clast4 mRNA and protein are highly expressed within the cytoplasm of growing oocytes. The Clast4 protein is stable during this developmental window and post-translationally modified by phosphorylation upon oocyte meiotic maturation. Additionally, we show that Clast4 and eIF4E directly interact by means of a canonical and functional eIF4E-binding motif. Our results suggest that Clast4, similar to Drosophila Cup, may act at the translational level during murine female germ-line development.
Villaescusa
J Carlos
JC
CEINGE-Biotecnologie Avanzate, Via Comunale Margherita 482, 80145 Napoli, Italy.
Allard
Patrick
P
Carminati
Emanuela
E
Kontogiannea
Maria
M
Talarico
Daniela
D
Blasi
Francesco
F
Farookhi
Riaz
R
Verrotti
Arturo C
AC
D020413:3' Untranslated Regions; D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D003593:Cytoplasm / Q000378:metabolism; D039561:Eukaryotic Initiation Factor-4E / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008540:Meiosis / Q000502:physiology*; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D019913:Nuclear Localization Signals; D029543:Nucleocytoplasmic Transport Proteins / Q000378:metabolism; D009865:Oocytes / Q000378:metabolism*; D010053:Ovary / Q000378:metabolism; D010766:Phosphorylation; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques
D020413:3' Untranslated Regions; C411571:EIF4ENIF1 protein, human; D039561:Eukaryotic Initiation Factor-4E; D019913:Nuclear Localization Signals; D029543:Nucleocytoplasmic Transport Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger