Chinese Bulletin of Botany ›› 2022, Vol. 57 ›› Issue (3): 276-287.DOI: 10.11983/CBB22018

• EXPERIMENTAL COMMUNICATIONS • Previous Articles     Next Articles

Cloning and Functional Analysis of Rice Yellow Green Leaf Regulatory Gene YGL18

Kairu Yang1, Qiwei Jia1, Jiayi Jin1, Hanfei Ye1, Sheng Wang1, Qianyu Chen1, Yian Guan1, Chenyang Pan1, Dedong Xin1, Yuan Fang1,*(), Yuexing Wang2,*(), Yuchun Rao1,*()   

  1. 1College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
    2State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, China
  • Received:2022-01-19 Accepted:2022-03-18 Online:2022-05-01 Published:2022-05-18
  • Contact: Yuan Fang,Yuexing Wang,Yuchun Rao

Abstract: Leaf color mutants are often accompanied by changes in chlorophyll content and abnormal chloroplast structure, and serve as essential materials for studying the functions of chloroplast development and photosynthesis-related genes. In this study, we obtained a yellow-green leaf mutant named yellow-green leaf 18 (ygl18) from Oryza sativa subsp. indica cv. ‘HZ’ with ethyl methanesulfonate (EMS). Compared with the wild type, the leaves of ygl18 turned yellow at three-leaf stage and the degree of yellowing increased as it grew, accompanied by decreasing photosynthetic rate and chlorophyll content. The seed-setting rate, 1 000-grain weight, and effective panicle number were significantly lower than those of the wild type. We observed disordered chloroplast structure, loose stromal lamellas, and stalled development in the mutant using transmission electron microscopy. Genetic analysis indicated that the mutant feature (or phenotype) of ygl18 is controlled by a pair of recessive nuclear alleles, which were located in a 115.2 kb region between markers InDel2 and InDel3 on the long arm of chromosome 3. We found mutations in the 5′UTR of LOC_Os03g48040 encoding FdC2 (ferredoxin C2). The gene’s function on controlling the mutant phenotype was verified using CRISPR transgenic experiments. Our results revealed a genetic basis for leaf color regulatory network and provide new clues for breeding photosynthetically efficient rice varieties in the future.

Key words: Oryza sativa (rice), leaf color variation, genetic analysis, map-based cloning, ferredoxin