两个水稻D2基因等位突变体的表型分析及分子鉴定  

Phenotypic Analysis and Molecular Characterization of Two Allelic Mutants of D2 Gene in Rice

作　　者：秦雁玲[1,2] 尹亮 赵金凤[2] 孙伟 赵庆雷 袁守江 朱文银 郭宝太[1] 李学勇[2] 

机构地区：[1]青岛农业大学生命科学学院,山东青岛266109 [2]中国农业科学院作物科学研究所/农作物基因资源与基因改良国家重大科学工程,北京100081 [3]山东省水稻研究所,山东济南250100

出　　处：《作物学报》2013年第6期1013-1020,共8页Acta Agronomica Sinica

基　　金：国家重点基础研究发展计划(973计划)项目(2013CBA01401);国家自然科学基金项目(31000696)资助

摘　　要：通过EMS诱变粳稻品种日本晴,筛选到2个矮秆突变体s1-46和s1-96。突变体株高分别为野生型的44.7%和55.9%,且叶片直立,穗粒数减少,籽粒变短。暗处理时,野生型的中胚轴伸长,但突变体的不伸长,说明突变性状与油菜素内酯(BR)相关。外源活性BR处理后,突变体与野生型的叶夹角均变大,根长均变短,表明突变基因与BR的生物合成相关。遗传分析表明,该突变性状由1对隐性基因控制。通过与籼稻品种Dular杂交构建F2群体,将该基因定位在第1染色体40.9kb范围内。测序表明,该基因与参与BR生物合成的D2基因等位,其中s1-46第305位的氨基酸由脯氨酸突变成亮氨酸,而s1-96第370位的甘氨酸突变成谷氨酸。Two dwarf mutants sl-46 and sl-96 were isolated from an EMS mutated japonica cultivar Nipponbare. The plant height of the two mutants was 44.7% and 55.9% of that of the wild-type, respectively. The mutants also exhibited erect leaves, reduced grain number, and shortened grains. When grown in complete darkness, the mesocotyl elongated in the wild-type plant, but not in the mutants, indicating that sl-46 and sl-96 are brassinosteroids （BRs）-related mutants. Furthermore, treatment of seed- ling with bioactive BR showed that the leaf angle was increased and the root length was decreased in both the wild-type and mu- tant plants, suggesting that the mutated gene is involved in BR biosynthesis. Genetic analysis showed that the phenotypes of both mutants were caused by a recessive gene. Fine-mapping showed that this gene was located within a 40.9 kb region on chromo- some 1. Sequence analysis revealed that the mutated gene was allelic to D2, encoding CYP90D2 that is involved in BR biosyn- thesis. In sl-46 and sl-96, the encoded amino acids were changed from proline to leucine and from glycine to glutamic acid at the 305th and 370th positions of D2, respectively.

关 键 词：水稻 矮秆突变体 油菜素内酯 精细定位 

分 类 号：S511[农业科学—作物学]