A New GA-Insensitive Semidwarf Mutant of Rice (Oryza sativa L.) with a Missense Mutation in the SDG Gene
A New GA-Insensitive Semidwarf Mutant of Rice (Oryza sativa L.) with a Missense Mutation in the SDG Gene
复制标题
一种新的对 GA 不敏感的水稻半矮秆突变体 (Oryza sativa L.)，其 SDG 基因存在错义突变
DOI：
10.1007/s11105-011-0321-6
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发表时间：
2012-02-01
影响因子：
2.1
通讯作者：
Liang, Guo-Hua
中科院分区：
文献类型：
--
作者：
Sui, Jiong-Ming;Guo, Bao-Tai;Liang, Guo-Hua
新桂矮是由双矮突变体新桂矮双矮与野生型品种南粳6号杂交选育而成的籼稻半矮秆系。半矮秆表型受半矮秆基因sdg控制。对矮秆突变体第二次叶鞘伸长和芽伸长的反应表明，sdg对赤霉素不敏感，其内源赤霉素含量高于野生型。通过图位克隆法克隆了SDG基因，测序分析表明SDG基因编码区发生了单核苷酸替换，导致一个氨基酸由丙氨酸变为苏氨酸。根据突变体和野生型材料的序列设计了一个切割扩增多态性序列标记。该序列标记可用于区分野生型和突变型，从而可用于分子标记辅助选择。通过导入野生型SDG基因，sdg突变体的矮化表型恢复为正常表型。水稻转化实验和GUS染色结果表明，SDG基因主要在营养器官中表达。
A semidwarf line of Indica rice, Xinguiai, was derived from the progeny of a cross between the double dwarf mutant Xinguiaishuangai and the wild-type variety Nanjing 6. The semidwarf phenotype was controlled by the semidwarf gene, sdg. The second sheath and shoot elongation responses of the dwarf mutant to exogenous gibberellin (GA3) showed that sdg was insensitive to gibberellin (GA), and its endogenous GAs content was higher than that in wild-type cultivars. The SDG gene was cloned by a map-based cloning method and sequencing analysis revealed that the coding region of sdg had a single nucleotide substitution resulting in a single amino acid change from alanine to threonine. A cleaved amplified polymorphic sequence marker was designed according to sequences from mutant and wild-type materials. This sequence marker could be used to distinguish wild types and mutants, and thus, could be used for molecular marker-assisted selection. The dwarf phenotype of the sdg mutant was restored to a normal phenotype by introducing the wild-type SDG gene. Rice transformation experiments and GUS staining demonstrated that the SDG gene was predominantly expressed in vegetative organs.