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Alternatively spliced transcripts from the Drosophila eIF4E gene produce two different Cap-binding proteins.

C A Lavoie·P E Lachance·N Sonenberg·P Lasko
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Abstract

Eukaryotic initiation factor 4E (eIF4E) is the subunit of eIF4F that binds to the cap structure at the 5' end of messenger RNA and is a critical component for the regulation of translation initiation. Using 7-methyl-GTP-Sepharose affinity chromatography, two distinct cap-binding proteins that migrate on SDS-polyacrylamide gel electrophoresis at approximately 35 kDa were purified from Drosophila adults. Peptide microsequence analysis indicated that these two proteins differ at their amino termini. Analysis of a set of cDNA clones encoding eIF4E led to the conclusion that the two different protein isoforms, which we term eIF4EI and eIF4EII, result from three alternatively spliced transcripts from a single eIF4E gene, which maps to region 67A8-B2 on polytene chromosomes. The three eIF4E transcripts also vary greatly in the lengths of their 5'-UTRs, suggesting the possibility of complex translational control of expression of the two eIF4E isoforms.

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Alternative SplicingAmino Acid SequenceAnimalsBase SequenceDNA PrimersDrosophila melanogasterEukaryotic Initiation Factor-4EExonsGenes, InsectIn Situ HybridizationIntronsMiceMolecular Sequence DataPeptide Initiation FactorsPolymerase Chain ReactionRNA Cap-Binding ProteinsRNA-Binding ProteinsSaccharomyces cerevisiaeSequence Homology, Amino AcidTranscription, GeneticTriticumComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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C A Lavoie, P E Lachance, N Sonenberg, P Lasko. 1996-07-05. Alternatively spliced transcripts from the Drosophila eIF4E gene produce two different Cap-binding proteins.. https://doi.org/10.1074/jbc.271.27.16393

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