Quality and Safety Institute of Agricultural Products, Heilongjiang Academy of Agricultural Sciences, Harbin, Heilongjiang, China.
Key Laboratory of Safety and Quality of Cereals and Their Products for State Market Regulation, Harbin, Heilongjiang, China.
BMC Genomics. 2024 Sep 11;25(1):852. doi: 10.1186/s12864-024-10754-9.
Low levels of the essential amino acid lysine in maize endosperm is considered to be a major problem regarding the nutritional quality of food and feed. Increasing the lysine content of maize is important to improve the quality of food and feed nutrition. Although the genetic basis of quality protein maize (QPM) has been studied, the further exploration of the quantitative trait loci (QTL) underlying lysine content variation still needs more attention.
Eight maize inbred lines with increased lysine content were used to construct four double haploid (DH) populations for identification of QTLs related to lysine content. The lysine content in the four DH populations exhibited continuous and normal distribution. A total of 12 QTLs were identified in a range of 4.42-12.66% in term of individual phenotypic variation explained (PVE) which suggested the quantitative control of lysine content in maize. Five main genes involved in maize lysine biosynthesis pathways in the QTL regions were identified in this study.
The information presented will allow the exploration of candidate genes regulating lysine biosynthesis pathways and be useful for marker-assisted selection and gene pyramiding in high-lysine maize breeding programs.
玉米胚乳中必需氨基酸赖氨酸含量低被认为是食品和饲料营养质量的一个主要问题。提高玉米的赖氨酸含量对于改善食品和饲料的营养质量非常重要。尽管已经研究了优质蛋白玉米（QPM）的遗传基础，但对赖氨酸含量变化相关的数量性状位点（QTL）的进一步探索仍需要更多关注。
使用 8 个赖氨酸含量增加的玉米自交系构建了四个双单倍体（DH）群体，以鉴定与赖氨酸含量相关的 QTL。四个 DH 群体的赖氨酸含量表现出连续的正态分布。在个体表型变异解释（PVE）方面，共鉴定出 12 个 QTL，范围在 4.42%-12.66%之间，表明玉米赖氨酸含量的数量控制。本研究在 QTL 区域中鉴定出了参与玉米赖氨酸生物合成途径的 5 个主要基因。
本研究提供的信息将有助于探索调节赖氨酸生物合成途径的候选基因，并可用于高赖氨酸玉米育种计划中的标记辅助选择和基因聚合。
