Linking heat and adaptive responses across temporal proteo-transcriptome and physiological traits of Solidago canadensis

Proteo-transcriptomic landscape provides new perspectives on how invasive plants response to increasing climatic extremes triggered by global warming. Plants that colonize broad ranges across pronounced climatic gradients offer a unique opportunity to evaluate temperature effects on molecular events as a function of their adaptive response to heat stress. Here, we used Solidago canadensis as a model species to characterize the dynamics of the physiological and proteo-transcriptomic changes that occurred in S. canadensis over four time points (0, 1, 3, and 6 h) in response to acute heat stress. A total of 98,643 unigenes and 7370 proteins were identified, and 12,676 unigenes and 248 proteins were differentially expressed under heat stress. Transcriptomic responses to heat stress were dominated by early occurring protein stability maintenance, and late adjustments of photosynthesis and secondary metabolism. However, only early responses extended to protein levels. Furthermore, heat stress also substantially altered physiological traits, although we did not observe any visible external damage to the leaves. Weighted gene co-expression network analysis highlighted core genes and proteins differentially expressed within modules highly correlated to physiological traits. Together, these results indicate that S. canadensis may transfer energy into the unfolded protein response and endoplasmic reticulum associated degradation mechanisms to response to heat stress, at the expense of photosynthesis and secondary metabolic processes. We suggest a theory for the molecular mechanisms underlying the heat response and adaptation in S. canadensis, which may help to explain the invasion potential of alien species that colonize a warmer environment.