Single Nucleotide Mutagenesis of the TaCHLI Gene Suppressed Chlorophyll and Fatty Acid Biosynthesis in Common Wheat Seedlings

作者：Chaojie Wang, Chaojie Wang, Lili Zhang, Yingzhuang Li, Zeeshan Ali Buttar, Na Wang, Yanzhou Xie, Chengshe Wang, Chengshe Wang · 发表于：Frontiers in Plant Science · 年份：2020 · DOI：10.3389/fpls.2020.00097 · 被引用次数：28 · 研究领域：Photosynthetic Processes and Mechanisms、Plant Molecular Biology Research、Plant Gene Expression Analysis

Wheat (Triticum aestivum L.) is one of the most important crops in the world. Chlorophyll, which is the major component in plant photosynthetic tissues, plays a vital role in plant development, crop improvement and further determines the crop productivity to a certain extent. The biosynthesis of chlorophyll remains a complex metabolic process, of which the leaf color mutants could be an effective resource to study the chlorophyll biosynthesis. In this study, we have identified a chlorophyll deficiency mutant, known as chli, from the wheat cultivar Shaannong33. chli exhibited obvious pale green leaf color at one-leaf stage with significantly decreased chlorophyll, Proto IX and Mg-Proto IX contents. Interestingly, a higher Proto IX to Mg-Proto IX ratio was observed in chli. The lipid biosynthesis in chli leaf and seed was also affected, displaying significantly reduced total lipid contents relative to Shaanong33. Genetic analysis indicated that the pale green leaf phenotype was controlled by a single pair of recessive nuclear gene. This mutant gene was mapped to an interval between 670-680 Mb on the wheat chromosome arm 7AL by SNP chip assay, within which the gene TraesCS7A01G480700.1 was predicted as the candidate target gene. Sequence alignment further revealed a single-nucleotide mutation (G664A) in the gene TraesCS7A01G480700.1 of chli which encoded I subunit of the Mg-chelatase in plants. This single-nucleotide mutation resulted in an amino acid substitution (D221N) in the...