Plant Cell 2019 Jun 16;31(6):1222-1237. Epub 2019 Apr 16.
Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain
Understanding how plants adapt to ambient temperatures has become a major challenge prompted by global climate change. This has led to the identification of several genes regulating the thermal plasticity of plant growth and flowering time. However, the mechanisms accounting for the natural variation and evolution of such developmental plasticity remain mostly unknown. In this study, we determined that natural variation at (), which interacts genetically with its homolog , alters growth and flowering time plasticity in relation to temperature in Arabidopsis (). Transgenic analyses demonstrated multiple functional effects for and supported the notion that structural polymorphisms in likely underlie its natural variation. Two major haplogroups carrying distinct functionally active alleles showed high frequency, strong geographic structure, and significant associations with climatic variables related to annual and daily fluctuations in temperature. Genome analyses across the plant phylogeny indicated that the prevalent plant genes encoding two tRNA guanylyl transferase 1 units evolved ∼120 million years ago during the early divergence of mono- and dicotyledonous clades. In addition, duplication occurred specifically in the Camelineae tribe (Brassicaceae). Thus, appears to be ubiquitous across plant evolution and likely contributes to climate adaptation through modifications of thermal developmental plasticity in Arabidopsis.