Identification of a new mutant allele of ZmYSL2 that regulates kernel development and nutritional quality in maize

Yikai Wang; Xiao Zhang; Bowen Luo; Hongmei Hu; Haixu Zhong; Haiying Zhang; Zhicheng Zhang; Jiajia Gao; Dan Liu; Ling Wu; Shiqiang Gao; Duojiang Gao; Shibin Gao

doi:10.1007/s11032-022-01278-9

Identification of a new mutant allele of ZmYSL2 that regulates kernel development and nutritional quality in maize

Mol Breed. 2022 Jan 29;42(2):7. doi: 10.1007/s11032-022-01278-9. eCollection 2022 Feb.

Authors

Yikai Wang^{1

2}, Xiao Zhang^{1

2}, Bowen Luo^{1

2}, Hongmei Hu^{1

2}, Haixu Zhong^{1

2}, Haiying Zhang^{1

2}, Zhicheng Zhang^{1

2}, Jiajia Gao^{1

2}, Dan Liu^{1

2}, Ling Wu^{1

2}, Shiqiang Gao^{1

2}, Duojiang Gao^{1

2}, Shibin Gao^{1

2

3}

Affiliations

¹ Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130 Sichuan China.
² Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture, Chengdu, 611130 Sichuan China.
³ State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, 611130 Sichuan China.

Abstract

The discovery and characterization of the opaque endosperm gene provide ideas and resources for the production and application of maize. We found an o213 mutant whose phenotype was opaque and shrunken endosperm with semi-dwarf plant height. The protein, lipid, and starch contents in the o213 endosperm were significantly decreased, while the free amino acid content in the o213 endosperm significantly increased. The aspartic acid, asparagine, and lysine contents were raised in the o213 endosperm by 6.5-, 8.5-, and 1.7-fold, respectively. Genetic analysis showed that this o213 mutant is a recessive single-gene mutation. The position mapping indicated that o213 is located in a 468-kb region that contains 11 protein-encoding genes on the long arm of chromosome 5. The coding sequence analysis of candidate genes between the WT and o213 showed that ZmYSL2 had only a single-base substitution (A-G) in the fifth exon, which caused methionine substitution to valine. Sequence analysis and the allelic test showed that o213 is a new mutant allele of ZmYSL2. The qRT-PCR results indicated that o213 is highly expressed in the stalks and anthers. Subcellular localization studies showed that o213 is a membrane transporter. In the variation analysis of o213, the amplification of 65 inbred lines in GWAS showed that this 3-bp deletion of the first exon of o213 was found only in temperate inbred lines, implying that the gene was artificially affected in the selection process. Our results suggest that o213 is an important endosperm development gene and may serve as a genetic resource.

Supplementary information: The online version contains supplementary material available at 10.1007/s11032-022-01278-9.

Keywords: Gene mapping; Kernel development; Maize (Zea mays); Nutritional quality.