生物技术通报2026，Vol.42Issue(9)：107-119,13.DOI:10.13560/j.cnki.biotech.bull.1985.2025-1203
谷子赖氨酸合成通路基因的鉴定及AK基因变异调控作用分析
Identification of Lysine Synthesis Pathway Genes and Analysis of the Regulation of AK Gene Variations in Foxtail Millet
摘要
Abstract
[Objective]Lysine is the first limiting essential amino acid for humans and livestock,and its low content restricts the improvement of nutritional quality in foxtail millet(Setaria italica L.).Elucidating the molecular mechanisms of lysine biosynthesis and metabolism in foxtail millet is essential for providing genetic resources for improving grain nutritional quality.[Method]The genes involved in the lysine biosynthesis pathway(LBPG)were identified via bioinformatics.Key candidate genes regulating grain lysine accumulation were explored by combining phylogenetic analysis,chromosomal localization,collinearity analysis,expression profiling,candidate gene association analysis,and haplotype analysis.[Result]The lysine content in foxtail millet grains declined during grain development(S1-S4),and the variation coefficient of lysine content in natural populations was 36.5%.Based on Kyoto encyclopedia of genes and genomes(KEGG)database annotation and foxtail millet genome information,a total of 15 genes encoding lysine synthesis-related enzymes were identified,belonging to 7 gene families.LBPGs(lysine biosynthesis pathway genes)exhibited tissue-specific and stage-specific expression,with most genes showing down-regulation in the panicle from the S1 to S4 stages.Candidate gene association analysis showed that 30 single nucleotide polymorphisms(SNPs)within four members of the aspartate kinase(AK)family(AK1,AK3,AK4,and AK5)were significantly associated with lysine content(P<0.01).Specifically,accessions carrying the AK3 Hap1 and AK5 Hap1 haplotypes exhibited 17.22%and 12.96%higher lysine content,respectively,than those carrying the Hap2 haplotypes.Protein interaction network and expression correlation analyses indicated that the homoserine kinase(HSK)gene interacted with AK3 and had a significantly positive expression correction(P<0.01).And it may modulate lysine synthesis by regulating the expression of AK3.[Conclusion]Lysine content in foxtail millet grains decreases as the grain matures.SNPs in AK family genes are key factors influencing lysine variation.Hap1 of AK3 and AK5 are superior haplotypes for high-lysine breeding.Furthermore,the HSK gene likely acts in coordination with AK3 to regulate lysine biosynthesis in foxtail millet grains.关键词
谷子/赖氨酸合成通路/候选基因关联分析/AK基因/单倍型Key words
Setaria italica/lysine synthesis pathway/candidate gene association analysis/AK gene/haplotype引用本文复制引用
赵雄伟,邵莉桃,李梦晴,梁逸萱,张洁如,曹艳花..谷子赖氨酸合成通路基因的鉴定及AK基因变异调控作用分析[J].生物技术通报,2026,42(9):107-119,13.基金项目
国家自然科学基金项目(32241041,32372062),山西省回国留学人员科研资助项目(2022-093) （32241041,32372062）
