超甜玉米bt2基因SNP位点的分析及分子标记辅助筛选

Protomer region of super sweet corn bt2 gene and development of molecular marker-assisted selection

【目的】利用等位基因特异PCR技术对超甜玉米的基因型进行分子鉴定,建立根据单核苷酸多态性(SNP)进行分子标记辅助筛选的平台。【方法】根据超甜玉米基因bt2启动子区域序列设计引物,通过等位基因特异PCR扩增,对PCR产物进行测序,利用ClustalX软件,分析比较了32份超甜玉米自交系bt2基因启动子区域的核苷酸序列,并进行了分子鉴定。【结果】在扩增的888bp序列中有3个SNP位点,分别在bt2基因转录起始上游的-20,-103和-107bp处,通过对32份超甜玉米自交系的SNP位点分析,将其区分为AAA和GGG 2种单体型。【结论】利用3个SNP位点中的-103(A/G)位点进行等位基因特异PCR,成功地鉴定了超甜玉米自交系的基因型,建立了通过等位基因特异PCR辅助筛选bt2基因的平台。

【Objective】 This study aimed to identify the genotype of super sweet corn inbred lines through allele specific PCR and establish the platform of molecular marker-assisted selection by single-nucleotide polymorphism（SNP）.【Method】 PCR primer was designed based on bt2 gene promoter region in super sweet corn.After being amplified,PCR primers from 32 super sweet corns were sequenced,analyzed and compared by software ClustalX.【Result】 Three SNPs were detected in an amplified 888 bp nucleotide sequence.They were at-20 bp,-103 bp and-107 bp sites upstream of transcription starting site of bt2 gene,respectively.The inbred lines of these 32 sweet corns were divided into two haplotypes（GGG and AAA）.【Conclusion】 Using one（-103 bp） of the three SNPs（A/G） loci,we successfully identified the genotype of super sweet corn inbred lines,and established the platform for selecting bt2 gene through allele specific PCR.