Striking circadian neuron diversity and cycling of Drosophila alternative splicing
- University of California, Berkeley, United States
- Howard Hughes Medical Institute, Brandeis University, United States
Abstract
Although alternative pre-mRNA splicing (AS) significantly diversifies the neuronal proteome, the extent of AS is still unknown due in part to the large number of diverse cell types in the brain. To address this complexity issue, we used an annotation-free computational method to analyze and compare the AS profiles between small specific groups of Drosophila circadian neurons. The method, the Junction Usage Model (JUM), allows the comprehensive profiling of both known and novel AS events from specific RNA-seq libraries. The results show that many diverse and novel pre-mRNA isoforms are preferentially expressed in one class of clock neuron and also absent from the more standard Drosophila head RNA preparation. These AS events are enriched in potassium channels important for neuronal firing, and there are also cycling isoforms with no detectable underlying transcriptional oscillations. The results suggest massive AS regulation in the brain that is also likely important for circadian regulation.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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The PSI-U1 snRNP interaction regulates male mating behavior in DrosophilaPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE79916).
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RNA-seq analysis of Drosophila clock and non-clock neurons reveals neuron-specific cycling and novel candidate neuropeptidesPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE77451).
Article and author information
Author details
Katharine C Abruzzi
Funding
Arnold and Mabel Beckman Foundation (Postdoctoral Fellowship)
- Qingqing Wang
Howard Hughes Medical Institute
- Michael Rosbash
National Institutes of Health (R01GM097352)
- Donald C Rio
National Institutes of Health (R35GM118121)
- Donald C Rio
National Institutes of Health (NIH P50102706)
- Donald C Rio
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Wang 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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Striking circadian neuron diversity and cycling of Drosophila alternative splicing
eLife 7:e35618.
https://doi.org/10.7554/eLife.35618
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