Conservation and divergence of gene expression plasticity following c. 140 million years of evolution in lodgepole pine (Pinus contorta) and interior spruce (Picea glauca × Picea engelmannii)

Authors

  • Sam Yeaman,

    1. Department of Botany, 6270 University Blvd, University of British Columbia, Vancouver, BC, Canada
    2. Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada
    Search for more papers by this author
    • These authors contributed equally to this work.
  • Kathryn A. Hodgins,

    1. Department of Botany, 6270 University Blvd, University of British Columbia, Vancouver, BC, Canada
    2. Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada
    3. School of Biological Sciences, Monash University, Melbourne, Vic., Australia
    Search for more papers by this author
    • These authors contributed equally to this work.
  • Haktan Suren,

    1. Department of Forest Resources and Environmental Conservation, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
    2. Genetics, Bioinformatics and Computational Biology Program, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
    Search for more papers by this author
  • Kristin A. Nurkowski,

    1. Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada
    Search for more papers by this author
  • Loren H. Rieseberg,

    1. Department of Botany, 6270 University Blvd, University of British Columbia, Vancouver, BC, Canada
    Search for more papers by this author
  • Jason A. Holliday,

    1. Department of Forest Resources and Environmental Conservation, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
    Search for more papers by this author
  • Sally N. Aitken

    Corresponding author
    1. Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada
    • Author for correspondence:

      Sally N. Aitken

      Tel: +1 604 822 6020

      Email: sally.aitken@ubc.ca

    Search for more papers by this author

Summary

  • Species respond to environmental stress through a combination of genetic adaptation and phenotypic plasticity, both of which may be important for survival in the face of climatic change.
  • By characterizing the molecular basis of plastic responses and comparing patterns among species, it is possible to identify how such traits evolve. Here, we used de novo transcriptome assembly and RNAseq to explore how patterns of gene expression differ in response to temperature, moisture, and light regime treatments in lodgepole pine (Pinus contorta) and interior spruce (a natural hybrid population of Picea glauca and Picea engelmannii).
  • We found wide evidence for an effect of treatment on expression within each species, with 6413 and 11 658 differentially expressed genes identified in spruce and pine, respectively. Comparing patterns of expression among these species, we found that 74% of all orthologs with differential expression had a pattern that was conserved in both species, despite 140 million yr of evolution. We also found that the specific treatments driving expression patterns differed between genes with conserved versus diverged patterns of expression.
  • We conclude that natural selection has probably played a role in shaping plastic responses to environment in these species.

Ancillary