Insights into electrosensory organ development, physiology and evolutionfrom a lateral line-enriched transcriptome
- University of Cambridge, United Kingdom
- The University of Texas at Austin, United States
- Museo Nacional de Ciencias Naturales-MNCN-CSIC, Spain
- Kennesaw State University, United States
Abstract
The anamniote lateral line system, comprising mechanosensory neuromasts and electrosensory ampullary organs, is a useful model for investigating the developmental and evolutionary diversification of different organs and cell types. Zebrafish neuromast development is increasingly well understood, but neither zebrafish nor Xenopus is electroreceptive and our molecular understanding of ampullary organ development is rudimentary. We have used RNA-seq to generate a lateral line-enriched gene-set from late-larval paddlefish (Polyodon spathula). Validation of a subset reveals expression in developing ampullary organs of transcription factor genes critical for hair cell development, and genes essential for glutamate release at hair cell ribbon synapses, suggesting close developmental, physiological and evolutionary links between non-teleost electroreceptors and hair cells. We identify an ampullary organ-specific proneural transcription factor, and candidates for the voltage-sensing L-type Cav channel and rectifying Kv channel predicted from skate (cartilaginous fish) ampullary organ electrophysiology. Overall, our results illuminate ampullary organ development, physiology and evolution.
Data availability
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Data from: Insights into electrosensory organ development, physiology and evolution from a lateral line-enriched transcriptomePublicly available at the NCBI Gene Expression Omnibus (accession no: GSE92470).
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (BB/F00818X/1)
- Clare VH Baker
Leverhulme Trust (RPG-383)
- Clare VH Baker
Fisheries Society of the British Isles (Research Grant)
- Melinda S Modrell
National Science Foundation (IOS 1557857)
- Harold H Zakon
National Science Foundation (IOS 1144965)
- Marcus C Davis
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments were performed in accordance with the approved institutional guidelines and regulations of the Institutional Animal Care and Use Committee of Kennesaw State University (approved protocol #12-001).
Copyright
© 2017, Modrell 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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Insights into electrosensory organ development, physiology and evolutionfrom a lateral line-enriched transcriptome
eLife 6:e24197.
https://doi.org/10.7554/eLife.24197
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