With global warming and climate change, breeding crop plants tolerant to high-temperature stress is of immense significance. tRNA 2-thiolation is a highly conserved form of tRNA modification among living organisms.
A research team led by Prof. YAO Shanguo at Institute of Genetics and Developmental Biology of Chinese Academy of Sciences reported the identification of SLG1 (Slender Guy 1), which encodes the cytosolic tRNA 2-thiolation protein 2 (RCTU2) in rice. SLG1 plays a key role in the response of rice plants to high-temperature stress at both seedling and reproductive stages. Dysfunction of SLG1 results in plants with thermosensitive phenotype, while overexpression of SLG1 enhances the tolerance of plants to high temperature. SLG1 is differentiated between the two Asian cultivated rice subspecies, indica and japonica, and the variations at both promoter and coding regions lead to an increased level of thiolated tRNA and enhanced thermotolerance of indica rice varieties. The results demonstrate that the allelic differentiation of SLG1 confers indica rice to high-temperature tolerance, and tRNA thiolation pathway might be a potential target in the next generation rice breeding for the warming globe.
△ Selection model of the SLG1 alleles during domestication.SLG1 is diversified among wild rice accessions. The intimate association of tRNA thiolation and thermotolerance led to the artificial selection of the SLG1Ind allele for the adaptation of indica rice to geographical regions with high environmental temperature. Interestingly, the SLG1Tej allele was also subjected to selection during japonica domestication, which might be due to the dynamic response of tRNA thiolation to various environmental stresses46.
This work was published online in Nature Communications on October 28. PhD fellowXU Yufang and ZHANG Li graduated from University of Chinese Academy of Sciencescontributed equally to this work.Prof. YAO Shanguo and Prof. CHU Chengcai at Institute of Genetics and Developmental Biology of Chinese Academy of Sciences are the corresponding authors.
