Tempo and mode of gene expression evolution in the brain across primates
- University of Massachusetts Amherst, United States
- MAEBIOS, United States
- Kent State University, United States
- The University of Texas MD Anderson Cancer Center, United States
- Icahn School of Medicine at Mount Sinai, United States
- George Washington University, United States
- Washington University in St. Louis, United States
Abstract
Primate evolution has led to a remarkable diversity of behavioral specializations and pronounced brain size variation among species (Barton, 2012; DeCasien & Higham, 2019; Powell, Isler, & Barton, 2017). Gene expression provides a promising opportunity for studying the molecular basis of brain evolution, but it has been explored in very few primate species to date (e.g. Khaitovich et al., 2005; Khrameeva et al., 2020; Ma et al., 2022; Somel et al., 2009). To understand the landscape of gene expression evolution across the primate lineage, we generated and analyzed RNA-Seq data from four brain regions in an unprecedented eighteen species. Here we show a remarkable level of variation in gene expression among hominid species, including humans and chimpanzees, despite their relatively recent divergence time from other primates. We found that individual genes display a wide range of expression dynamics across evolutionary time reflective of the diverse selection pressures acting on genes within primate brain tissue. Using our samples that represents a 190-fold difference in primate brain size, we identified genes with variation in expression most correlated with brain size. Our study extensively broadens the phylogenetic context of what is known about the molecular evolution of the brain across primates and identifies novel candidate genes for study of genetic regulation of brain evolution.
Data availability
Sequencing data have been deposited in the Short Read Archive: BioProject PRJNA639850
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RNA-Seq of human astrocytesNCBI Gene Expression Omnibus, GSE73721.
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single cell RNA-seq from pyramidal cell (ENCLB928LID)NCBI Gene Expression Omnibus, GSE78331.
Article and author information
Author details
Courtney C Babbitt
Funding
National Science Foundation (BCS-1750377)
- Courtney C Babbitt
National Institutes of Health (T32 GM135096)
- Katherine Rickelton
James S. McDonnell Foundation (220020293)
- Chet C Sherwood
National Institutes of Health (NS-092988)
- Chet C Sherwood
National Science Foundation (SMA-1542848)
- Chet C Sherwood
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2024, Rickelton 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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Tempo and mode of gene expression evolution in the brain across primates
eLife 13:e70276.
https://doi.org/10.7554/eLife.70276
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