番茄短节间基因BRACHYTIC(BR)的精细定位及其候选基因特异性分子标记的开发

Fine Mapping and Candidate Gene-Specific Marker Development of the BRACHYTIC(BR)Gene in Tomato

番茄株型矮化紧凑有利于实现轻简化栽培。短节间突变位点brachytic(br)已经成功应用于番茄矮化育种。利用Heinz1706与含br位点的无限生长型樱桃番茄品种VFNT Cherry构建的F2分离群体,通过交换单株筛选及后代鉴定,将br位点定位到分子标记HP5589和ZP273之间约14.9 kb的范围内。根据番茄基因组注释信息ITAG 4.0版本,该区间存在2个基因Solyc01g066970和Solyc01g066980,均为开花促进因子(Flowering Promoting Factor 1,FPF1)的同源基因。第2代重测序数据分析发现VFNT Cherry中Solyc01g066980基因的大部分序列缺失。根据该序列变异开发了1个共显性PCR分子标记BRD,试验结果将有助于番茄株型分子改良和株高调控分子机理研究。

The dwarf and compact architecture of tomato conduces to the rapid adoption of agricultural practices.The brachytic(br)locus,which contributes to the short internode and plant dwarfism,has been successfully used in tomato breeding.In this study,we used Heinz1706 and VFNT Cherry,an indeterminate tomato variety containing the br locus,to construct a series of segregation populations.Through recombinant screening and progeny test,the br locus was delimited to a region of 14.9 kb between the molecular markers HP5589 and ZP273,and in this region,gene prediction analysis revealed two genes,Solyc01g066970 and Solyc01g066980,both of which are homologous to Arabidopsis Flowering Promoting Factor 1(FPF1).Genome resequencing and sequence comparison confirmed a large deletion of the Solyc01g066980 gene in VFNT Cherry.Based on this sequence polymorphism,a co-dominant PCR molecular marker BRD was developed to facilitate the rapid implementation of the br locus.The results will be very useful for tomato breeding programs and for a better understanding of the molecular mechanism of plant architecture and height manipulation.