The eukaryotic translation initiation factor eIF4E reprograms alternative splicing.

TitleThe eukaryotic translation initiation factor eIF4E reprograms alternative splicing.
Publication TypeJournal Article
Year of Publication2023
AuthorsGhram M, Morris G, Culjkovic-Kraljacic B, Mars J-C, Gendron P, Skrabanek L, Revuelta MVictoria, Cerchietti L, Guzman ML, Borden KLB
JournalEMBO J
Volume42
Issue7
Paginatione110496
Date Published2023 Apr 03
ISSN1460-2075
KeywordsAlternative Splicing, Eukaryotic Initiation Factor-4E, Eukaryotic Initiation Factors, Humans, Leukemia, Myeloid, Acute, Mutation, RNA Splicing, RNA Splicing Factors
Abstract

Aberrant splicing is typically attributed to splice-factor (SF) mutation and contributes to malignancies including acute myeloid leukemia (AML). Here, we discovered a mutation-independent means to extensively reprogram alternative splicing (AS). We showed that the dysregulated expression of eukaryotic translation initiation factor eIF4E elevated selective splice-factor production, thereby impacting multiple spliceosome complexes, including factors mutated in AML such as SF3B1 and U2AF1. These changes generated a splicing landscape that predominantly supported altered splice-site selection for ~800 transcripts in cell lines and ~4,600 transcripts in specimens from high-eIF4E AML patients otherwise harboring no known SF mutations. Nuclear RNA immunoprecipitations, export assays, polysome analyses, and mutational studies together revealed that eIF4E primarily increased SF production via its nuclear RNA export activity. By contrast, eIF4E dysregulation did not induce known SF mutations or alter spliceosome number. eIF4E interacted with the spliceosome and some pre-mRNAs, suggesting its direct involvement in specific splicing events. eIF4E induced simultaneous effects on numerous SF proteins, resulting in a much larger range of splicing alterations than in the case of mutation or dysregulation of individual SFs and providing a novel paradigm for splicing control and dysregulation.

DOI10.15252/embj.2021110496
Alternate JournalEMBO J
PubMed ID36843541
PubMed Central IDPMC10068332
Grant ListPJT 159785 / / CIHR / Canada
R01 CA098571 / CA / NCI NIH HHS / United States
R01 CA080728 / CA / NCI NIH HHS / United States