Exon Junction Complex proteins bind nascent transcripts independently of pre-mRNA splicing in Drosophila melanogaster
- University of Birmingham, United Kingdom
- Stowers Institute for Medical Research, United States
- Asan Medical Center, Republic of Korea
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.
Data availability
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Exon Junction Complex (EJC) proteins bind nascent transcripts independently of pre-mRNA splicing in Drosophila melanogasterPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE84595).
Article and author information
Author details
Funding
Wellcome (9340/Z/09/Z)
- Saverio Brogna
Leverhulme Trust (RPG-2014-291)
- Saverio Brogna
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Elisa Izaurralde, Max Planck Institute for Developmental Biology, Germany
Version history
- Received: July 21, 2016
- Accepted: November 21, 2016
- Accepted Manuscript published: November 23, 2016 (version 1)
- Version of Record published: December 15, 2016 (version 2)
Copyright
© 2016, Choudhury et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Exon Junction Complex proteins bind nascent transcripts independently of pre-mRNA splicing in Drosophila melanogaster
eLife 5:e19881.
https://doi.org/10.7554/eLife.19881
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