New genes and functional innovation in mammals
José Luis Villanueva-Cañas Jorge Ruiz-Orera M.Isabel Agea Maria Gallo David Andreu M.Mar Albà
Genome Biol Evol evx136. DOI: https://doi.org/10.1093/gbe/evx136
Published: 21 July 2017
Article history
Received: 09 February 2017 Revision Received: 17 May 2017
Revision Received: 29 June 2017 Accepted: 14 July 2017
Source/Fonte: Edvotek
Abstract
The birth of genes that encode new protein sequences is a major source of evolutionary innovation. However, we still understand relatively little about how these genes come into being and which functions they are selected for. To address these questions we have obtained a large collection of mammalian-specific gene families that lack homologues in other eukaryotic groups. We have combined gene annotations and de novo transcript assemblies from 30 different mamalian species, obtaining about 6,000 gene families. In general, the proteins in mammalian-specific gene families tend to be short and depleted in aromatic and negatively charged residues. Proteins which arose early in mammalian evolution include milk and skin polypeptides, immune response components, and proteins involved in reproduction. In contrast, the functions of proteins which have a more recent origin remain largely unknown, despite the fact that these proteins also have extensive proteomics support. We identify several previously described cases of genes originated de novo from non-coding genomic regions, supporting the idea that this mechanism frequently underlies the evolution of new protein-coding genes in mammals. Finally, we show that most young mammalian genes are preferentially expressed in testis, suggesting that sexual selection plays an important role in the emergence of new functional genes.
de novo gene, species-specific gene, lineage-specific gene, evolutionary innovation, adaptive evolution, mammals
Issue Section: Research article
Author notes
# Current address: Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Barcelona, Spain
© The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
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