水稻条白叶和白穗突变基因St-wp的遗传分析与精细定位

Genetic Analysis and Fine Mapping of St-wp Gene in Mutant Rice With Stripe White Leaf and White Panicle

为研究叶绿体的差异性发育,本文通过60Co-γ诱变籼稻93-11筛选获得条白叶片和白穗突变体。经遗传分析表明,该突变性状受单隐性核基因控制,暂命名为St-wp(stripe white leaf and white panicle)。突变基因St-wp被精细定位于第6染色体标记d CAMPs620和In Del620之间,物理距离为9.2kb,此区间内包含3个候选基因。测序对比发现,突变体基因组的核糖核苷二磷酸还原酶小亚基(ribonucleoside-diphosphate reductase small chain)编码区第308碱基由A变为T,导致谷氨酸突变为缬氨酸。该基因与已报道的水稻白条纹叶基因St1和Gws等位,但突变体st1和gws均未表现出白穗性状。本研究可为叶绿体组织差异性发育的深入研究提供依据。

The mutant with stripe white leaf and white panicle was induced from indica rice 93 -11 by 60Cobah gamma irradiation, in order to study the differential development of chloroplast. Genetic analysis indicated that the mutated trait was controlled by a single recessive nuclear gene, which was tentatively designed as St-wp. The mutated gene St-wp was finely mapped between the markers dCAMPs620 and InDel 630 on the chromosome 6, within a physical region of 9.2 kb containing three candidate genes. Sequence comparison showed a single nucleotide change （A308 -T308） in exon of LOC _OsO6g14620 （Ribonucleoside-diphosphate reductase small chain） in mutant st-wp, which caused a missense mutation of amino acid from Glu to Val. The mutated gene St-wp was allelic to the previously reported genes, green-white-stripe （Stl） and green-white-stripe （Gws） , while there were no white panicle phenotypes observed in both mutants of stl and gws.