烟草航天诱变突变体叶形遗传分析及基因定位

利用航天诱变方法获得烟草品种NC89的突变体NC89-M,与野生型相比,NC89-M叶形呈宽椭圆,叶面褶皱,叶缘呈锯齿状。为明确烟草航天诱变突变体NC89-M叶形突变机理,挖掘突变体叶形突变基因,利用NC89-M与烟草品系2014-168杂交获得F2群体,对F2群体遗传分析表明突变体叶形性状受1对显性主效基因控制。通过混合集团分离法,确定SSR标记PT60795与叶形性状连锁。利用已有的突变体基因组序列信息,开发InDel标记最终将突变基因nc89m定位于标记PT60795与InDel5之间,遗传距离分别为2.9 cM和4.4 cM。在该区间内发现在叶片中高表达的基因Nitab4.5_0000008g0880.1编码区第1 294个核苷酸发生突变,由腺嘌呤突变为胞嘧啶,其编码氨基酸由酪氨酸突变为天冬氨酸,因此将其作为nc89m的候选基因。本研究为Nitab4.5_0000008g0880.1的基因克隆及功能验证打下基础。

Leaf Shape Genetic Analysis and Gene Mapping of Tobacco Space Mutation Mutant

The mutant NC89-M was mutanted by tobacco NC89 using aerospace mutagenesis.Compared with the wild type,the leaf shape of the NC89-M is broadly elliptical,the leaf surface is folded,and the leaf edge is jagged.To clarify the mechanism of tobacco leaf-shaped space mutant NC89-M and excavate leaf-shape mutant gene.The F2 population was obtained by hybridization of NC89-M with the tobacco strain 2014-168.Genetic analysis among F2 population indicated that the mutant leaf shape was controlled by one pair of dominant genes.The SSR marker PT60795 was determined to be linked to the leaf shape trait by bulked segregant analysis.According to the mutant genome sequence,anew developed InDel marker mapped the mutated gene nc89 m between the markers PT60795 and InDel5 with genetic distances of 2.9 c M and 4.4 cM,respectively.In this interval,the 1294 thnucleotide of the coding region of the gene Nitab4.50000008 g0880.1 was found to be mutated from adenine to cytosine,and its encoded amino acid was mutated from tyrosine to aspartic acid.The gene expression is higher in the leaf,so it is used as a candidate gene for nc89 m.This study laid the foundation for the cloning and functional verification of the gene Nitab4.50000008 g0880.1.