The exon junction complex is required for definition and excision of neighboring introns in Drosophila

ABSTRACT: Splicing of pre-mRNAs results in the deposition of the exon junction complex (EJC) upstream of exon-exon boundaries. The EJC plays crucial post-splicing roles in export, translation, localization and nonsense-mediated decay of mRNAs. It also aids faithful splicing of pre-mRNAs containing large introns, albeit via an unknown mechanism. Here, we show that the core EJC plus the accessory factors RnpS1 and Acinus aid in definition and efficient splicing of neighboring introns. This requires prior deposition of the EJC in close proximity either from an upstream or downstream splicing event. If present in isolation, EJC-dependent introns are splicing-defective also in wildtype cells. Interestingly, the most affected intron belongs to the piwi locus, which explains the reported transposon de-silencing in EJC-depleted Drosophila ovaries. We propose that the dependency of splicing on the EJC is exploited as a means to control the temporal order of splicing events. Our observations provide a powerful basis to dissect the molecular events that underlie the role of the EJC in splicing. Analysis of splicing defects in 3 knockdowns (siGFP [control], siACN, siTSU) in Drosohpila OSCs. PolyA RNA (biological duplicates) and total-RNA was sequenced on a Illumina HiSeq2000 in PE50 mode.

ORGANISM(S): Drosophila melanogaster

SUBMITTER: Dominik Handler 

PROVIDER: E-GEOD-58830 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress