Species-Specific Epigenetic Signature Associate with Heat Stress Tolerance in a Perennial Tree Species Populus

ABSTRACT: Epigenetic regulation in annual plants is recognized as a key component of recurring stress adaptation, but reports on perennial tree species are limited. In this study, two contrasting tree species, Populus trichocarpa and Populus deltoides, and a F1 hybrid cross between them showed species-specific epigenetic and physiological responses to heat stress following priming. By analyzing whole-genome methylation, transcriptomics, proteomics, metabolomics, and photosynthesis parameters, we found that P. deltoides has adapted epigenetically to heat stress, resulting in improved photosynthetic efficiency compared to P. trichocarpa. Conversely, P. trichocarpa displayed stress signaling and defense mechanisms that could not sustain a net assimilation rate despite maintaining higher gas exchange. Heat stress following priming in hybrid plants increased transcript levels of thermotolerance-related transcription factors, such as SPL12. Selected regions in the promoter of SPL12 showed differential methylation between direct heat stress and priming followed by heat stress. This, in turn, resulted in the upregulation of downstream genes and associated increases in protein and metabolite abundance for stress adaptation. Consequently, hybrid plants showed enhanced photosynthesis and gas exchange rates, a trait lacking in P. trichocarpa. These results imply that priming may not be universally effective in enhancing plant performance under stress, particularly in perennial tree species. However, priming can acclimate the perennial tree species P. deltoides to withstand elevated temperature stress better. Our study has demonstrated that priming-based stress adaptation are species-specific but can be attained through crossbreeding, indicating its potential use in breeding programs.

INSTRUMENT(S): Q Exactive Plus

ORGANISM(S): Populus Trichocarpa X Populus Deltoides (ncbitaxon:3695) Populus Trichocarpa (ncbitaxon:3694) Populus Deltoides (ncbitaxon:3696) Populus (ncbitaxon:3689)

SUBMITTER: Paul Abraham  

PROVIDER: MSV000095335 | MassIVE | Mon Jul 15 05:06:00 BST 2024

SECONDARY ACCESSION(S): PXD053949

REPOSITORIES: MassIVE