Exon Junction Complex proteins bind nascent transcripts independently of pre-mRNA splicing in Drosophila melanogaster

Research output: Contribution to journalArticle

Authors

  • Subhendu Roy Choudhury
  • Tina McLeod
  • Marco Blanchette
  • Boyun Jang

Colleges, School and Institutes

Abstract

Although, it is currently understood that the exon junction complex (EJC) is recruited on spliced mRNA by a specific interaction between its central protein, eIF4AIII, and splicing factor CWC22, we found that eIF4AIII and the other EJC core proteins Y14 and MAGO bind the nascent transcripts of not only intron-containing but also intronless genes on Drosophila polytene chromosome. Additionally, Y14 ChIP-seq demonstrates that association with transcribed genes is also splicing-independent in Drosophila S2 cells. The association of the EJC proteins with nascent transcripts does not require CWC22 and that of Y14 and MAGO is independent of eIF4AIII. We also show that eIF4AIII associates with both polysomal and monosomal RNA in S2 cell extracts, while Y14 and MAGO fractionate separately. Cumulatively, our data indicate a global role of eIF4AIII in gene expression, which would be independent of Y14 and MAGO, splicing, and of the EJC, as currently understood.

Details

Original languageEnglish
JournalElife
Publication statusPublished - 23 Nov 2016