Evolutionary transcriptomics reveals the origins of olives and the genomic changes associated with their domestication

Muriel Gros-Balthazard, Guillaume Besnard, Gautier Sarah, Yan Holtz, Julie Leclercq, Sylvain Santoni, Daniel Wegmann, Sylvain Glémin, Bouchaib Khadari

Research output: Contribution to journalArticle

Abstract

The olive (Olea europaea L. subsp. europaea) is one of the oldest and most socio-economically important cultivated perennial crop in the Mediterranean region. Yet, its origins are still under debate and the genetic bases of the phenotypic changes associated with its domestication are unknown. We generated RNA-sequencing data for 68 wild and cultivated olive trees to study the genetic diversity and structure both at the transcription and sequence levels. To localize putative genes or expression pathways targeted by artificial selection during domestication, we employed a two-step approach in which we identified differentially expressed genes and screened the transcriptome for signatures of selection. Our analyses support a major domestication event in the eastern part of the Mediterranean basin followed by dispersion towards the West and subsequent admixture with western wild olives. While we found large changes in gene expression when comparing cultivated and wild olives, we found no major signature of selection on coding variants and weak signals primarily affected transcription factors. Our results indicated that the domestication of olives resulted in only moderate genomic consequences and that the domestication syndrome is mainly related to changes in gene expression, consistent with its evolutionary history and life history traits.

Original languageEnglish (US)
Pages (from-to)143-157
Number of pages15
JournalPlant Journal
Volume100
Issue number1
DOIs
StatePublished - Oct 1 2019

    Fingerprint

Keywords

  • Olea europaea (olive tree)
  • RNA-sequencing
  • artificial selection
  • differential expression analysis
  • domestication
  • perennial crop
  • transcriptomics

ASJC Scopus subject areas

  • Genetics
  • Plant Science
  • Cell Biology

Cite this

Gros-Balthazard, M., Besnard, G., Sarah, G., Holtz, Y., Leclercq, J., Santoni, S., Wegmann, D., Glémin, S., & Khadari, B. (2019). Evolutionary transcriptomics reveals the origins of olives and the genomic changes associated with their domestication. Plant Journal, 100(1), 143-157. https://doi.org/10.1111/tpj.14435