Identification of two recessive etiolation genes (py1, py2) in pakchoi (Brassica rapa L. ssp. chinensis)

作者：Kun Zhang, Mu Yu, Weijia Li, Xiaofei Shan, Nan Wang, Hui Feng · 发表于：BMC Plant Biology · 年份：2020 · DOI：10.1186/s12870-020-2271-3 · 被引用次数：12 · 研究领域：Plant Gene Expression Analysis、Photosynthetic Processes and Mechanisms、Plant nutrient uptake and metabolism

Abstract Background Leaf color is a major agronomic trait, which has a strong influence on crop yields. Isolating leaf color mutants can represent valuable materials for research in chlorophyll (Chl) biosynthesis and metabolism regulation. Results In this study, we identified a stably inherited yellow leaf mutant derived from ‘Huaguan’ pakchoi variety via isolated microspore culture and designated as pylm . This mutant displayed yellow leaves after germination. Its etiolated phenotype was nonlethal and stable during the whole growth period. Its growth was weak and its hypocotyls were markedly elongated. Genetic analysis revealed that two recessive nuclear genes, named py1 and py2 , are responsible for the etiolation phenotype. Bulked segregant RNA sequencing (BSR-Seq) showed that py1 and py2 were mapped on chromosomes A09 and A07, respectively. The genes were single Mendelian factors in F 3:4 populations based on a 3:1 phenotypic segregation ratio. The py1 was localized to a 258.3-kb interval on a 34-gene genome. The differentially expressed gene BraA09004189 was detected in the py1 mapping region and regulated heme catabolism. One single-nucleotide polymorphism (SNP) of BraA09004189 occurred in pylm. A candidate gene-specific SNP marker in 1520 F 3:4 yellow-colored individuals co-segregated with py1 . For py2 , 1860 recessive homozygous F 3:4 individuals were investigated and localized py2 to a 4.4-kb interval. Of the five genes in this region, BraA07001774 was predicted as ...