Intron and gene size expansion during nervous system evolution.
Ontology highlight
ABSTRACT: Background
The evolutionary radiation of animals was accompanied by extensive expansion of gene and genome sizes, increased isoform diversity, and complexity of regulation.Results
Here we show that the longest genes are enriched for expression in neuronal tissues of diverse vertebrates and of invertebrates. Additionally, we show that neuronal gene size expansion occurred predominantly through net gains in intron size, with a positional bias toward the 5' end of each gene.Conclusions
We find that intron and gene size expansion is a feature of many genes whose expression is enriched in nervous systems. We speculate that unique attributes of neurons may subject neuronal genes to evolutionary forces favoring net size expansion. This process could be associated with tissue-specific constraints on gene function and/or the evolution of increasingly complex gene regulation in nervous systems.
SUBMITTER: McCoy MJ
PROVIDER: S-EPMC7222433 | biostudies-literature | 2020 May
REPOSITORIES: biostudies-literature
Publications
Intron and gene size expansion during nervous system evolution.
McCoy Matthew J MJ Fire Andrew Z AZ
BMC genomics 20200514 1
<h4>Background</h4>The evolutionary radiation of animals was accompanied by extensive expansion of gene and genome sizes, increased isoform diversity, and complexity of regulation.<h4>Results</h4>Here we show that the longest genes are enriched for expression in neuronal tissues of diverse vertebrates and of invertebrates. Additionally, we show that neuronal gene size expansion occurred predominantly through net gains in intron size, with a positional bias toward the 5' end of each gene.<h4>Conc ...[more]
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