A large- effect fitness trade- off across environments is explained by a single mutation affecting cold acclimation

• 成果类型: Article
• 署名作者: Lee, Gwonjin; Sanderson, Brian J.; Ellis, Thomas J.; Dilkes, Brian P.; McKay, John K.; Agren, Jon; Oakley, Christopher G.
• 署名单位: Purdue University System; Purdue University; Purdue University System; Purdue University; Uppsala University; Purdue University System; Purdue University; Colorado State University System; Colorado State University Fort Collins; State University System of Florida; University of Florida; University of Kansas; University of Kansas; Austrian Academy of Sciences; Vienna Biocenter (VBC); Gregor Mendel Institute of Molecular Plant Biology (GMI)
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-13744
• DOI: 10.1073/pnas.2317461121
• 发表日期: 2024-02-06
• 关键词: locally adapted populations; freezing tolerance; arabidopsis-thaliana; quantitative traits; physiological-basis; natural variation; clinal variation; flowering time; southern range; genetic-basis

摘要

Identifying the genetic basis of local adaptation and fitness trade - offs across environments is a central goal of evolutionary biology. Cold acclimation is an adaptive plastic response for surviving seasonal freezing, and costs of acclimation may be a general mechanism for fitness trade - offs across environments in temperate zone species. Starting with locally adapted ecotypes of Arabidopsis thaliana from Italy and Sweden, we examined the fitness consequences of a naturally occurring functional polymorphism in CBF2. This gene encodes a transcription factor that is a major regulator of cold- acclimated freezing tolerance and resides within a locus responsible for a genetic trade - off for long - term mean fitness. We estimated the consequences of alternate genotypes of CBF2 on 5- y mean fitness and fitness components at the native field sites by comparing near- isogenic lines with alternate genotypes of CBF2 to their genetic background ecotypes. The effects of CBF2 were validated at the nucleotide level using gene- edited lines in the native genetic backgrounds grown in simulated parental environments. The foreign CBF2 genotype in the local genetic background reduced long - term mean fitness in Sweden by more than 10%, primarily via effects on survival. In Italy, fitness was reduced by more than 20%, primarily via effects on fecundity. At both sites, the effects were temporally variable and much stronger in some years. The gene- edited lines confirmed that CBF2 encodes the causal variant underlying this genetic trade - off. Additionally, we demonstrated a substantial fitness cost of cold acclimation, which has broad implications for potential maladaptive responses to climate change.