大豆品种北农103矮秆基因定位和候选基因克隆

Mapping and candidate gene cloning of dwarf gene in soybean cultivar Beinong 103

[目的]对北农103的矮秆基因进行定位和克隆,为研究和利用北农103及其矮秆基因奠定基础。[方法]以矮秆品种北农103与高秆品种海系13杂交构建的F5代重组自交系群体为材料,利用性状混池重测序技术结合分子标记分析,对源于北农103的矮秆基因进行定位,根据定位区间的基因注释信息,预测候选基因,并在双亲间克隆分析候选基因的序列变异信息。此外,在株高形成的关键发育时期,对候选基因进行表达动态模式分析。[结果]北农103携带的矮秆基因被定位于分子标记Satt 373和XH-8之间,遗传距离分别为0.8 cM和1.0 cM,对应于大豆品种Williams 82参考基因组的195 kb物理区间;候选基因IAA16序列分析表明,高秆品种海系13 DNA序列中的第1564位碱基为A,而矮秆品种北农103为C,导致北农103候选基因IAA16编码氨基酸由酪氨酸突变为丝氨酸;海系13在第1571位碱基为G,而北农103为C,导致北农103候选基因IAA16编码氨基酸由丝氨酸突变为苏氨酸。[结论]经DNA序列和蛋白结构分析推测,候选基因IAA16在北农103中发生变异,在海系13开花期该基因相对表达量显著高于北农103,推测IAA16的等位突变基因是调控北农103矮秆性状的基因。

[Objective]The candidate dwarf genes carried by Beinong 103 were researched by gene localization and cloning for research and utilization.[Methods]To mapping the dwarf gene from Beinong 103,The F5 generation recombinant inbred population constructed by crossing the dwarf variety Beinong 103 and the tall variety Haixi 13 was used as the material,and the traits mixed pool resequencing technology combined with molecular markers was used for analysis.The candidate genes were predicted according to the gene annotation information in the location interval,and the sequence variation information of the candidate genes was analyzed between parents.In addition,dynamic expression patterns of candidate genes were analyzed during the key period of plant height formation.[Result]The dwarf gene of Beinong 103 was located between the molecular markers Satt 373 and XH-8,and their genetic distance were 0.8 cM and 1.0 cM,respectively.The physical distance between the two markers corresponds to Williams 82 reference genome sequence 195 kb.The sequence analysis of the candidate gene IAA16 showed that A base of high male parent Haixi 13 changed to C of Beinong 103 in the 1564th base of DNA sequence,resulting in the nucleotide mutation from tyrosine to serine;the 1571th base in the DNA sequence,compared with Haixi 13,G changed to C in Beinong 103,resulting in the nucleotide mutation from serine to threonine.[Conclusion]According to the analysis of DNA sequence and protein structure,the candidate gene IAA16 has been mutated in Beinong 103.The relative expression of this gene in Haixi 13 was significantly higher than that of Beinong 103 during the flowering period.It is speculated that the allelic mutant gene of IAA16 is a gene that regulates the dwarf traits in Beinong 103.