极端粒形水稻粒宽基因GW2的序列分析和效应  

Sequence Analysis and Effect of Grain Width Genes GW2 in Rice Based on Extreme Materials in Grain Size

作　　者：张亚东[1,2] 梁彦丽[1,2] 郑佳[2] 丁丹[1,2] 赵春芳[2] 陈涛[2] 赵庆勇[2] 朱镇[2] 周丽慧[2] 姚姝[2] 赵凌[2] 于新[2] 王才林[2] 

机构地区：[1]南京农业大学农学院,南京210095 [2]江苏省农业科学院粮食作物研究所/江苏省优质水稻工程技术研究中心/国家水稻改良中心南京分中心,南京210014

出　　处：《中国水稻科学》2014年第6期581-588,共8页Chinese Journal of Rice Science

基　　金：国家自然科学基金资助项目(31271678);江苏省农业科技自主创新基金资助项目(CX[12]1003);江苏省科技支撑计划资助项目(BE2012303)

摘　　要：粒形是影响水稻产量的重要因子,对粒形相关基因的发掘和利用一直倍受重视。在已克隆的粒形基因中,GW2是一个控制粒宽的重要基因。通过同源克隆的方法,获得极端大粒水稻TD70和极端小粒水稻Kasalath的GW2基因cDNA片段,分析序列差异,设计功能标记,检测240个来源于TD70/Kasalath的重组自交系(RILs)和部分籼稻骨干恢复系、江苏省主栽粳稻品种的基因类型及其效应。结果表明,TD70的GW2与大粒粳稻WY3完全一致,与已知序列(GenBank:EF447275)相似性达99.77%,在碱基的第114位,T突变为C,但并不改变氨基酸性质;在第316位缺失碱基A,造成316位以后的所有碱基前移一位,氨基酸均发生变化,在碱基的第346、第347、第348位形成TAA的终止密码子,提前结束了TD70的GW2蛋白的表达。而Kasalath的GW2序列仅在碱基的第114位,由T突变为C,但并不改变氨基酸性质;GW2Kasalath的316位没有突变,表达没有提前终止;设计的dCAPs标记,产物经内切酶ApoI酶切,TD70为21bp和30bp两个片段,而Kasalath条带为51bp;240个RILs中含GW2TD70基因的株系有82个,含GW2Kasalath基因的株系有158个,两者在粒宽和粒重表型上存在显著差异;8个籼稻骨干恢复系和10个江苏省主栽粳稻品种中都不存在GW2TD70基因。GW2TD70基因对籽粒宽度有一定的调控作用,水稻育种中可以利用GW2TD70基因来提高籽粒粒重。Grain shape is one of the most important influencing factor to rice grain yield.Among all of the cloned grain shape genes,GW2 is an important one controlling grain width.We obtained the sequences of the important grain shape gene GW2 using cDNA cloning strategy from rice variety TD70 and Kasalath and design its functional marker based on gene sequence difference to analyze genotype and phenotype of recombinant inbred lines（RILs）from TD70/Kasalath cross,some indica restorer lines and japonica rice cultivars in Jiangsu Province.GW2 TD70 shared 100% identity to GW2 WY3 and 99.77% identity to GW2 sequence（GenBank：EF447275）and there exist a single nucleotide mutation at site 1 14 without changing amino acid,a single nucleotide deletion at site 3 1 6 which generate termination codon at site 346, 347 and 348,thus the expression of GW2 protein stopped in advance.The sequence of GW2 Kasalath showed 99.92% identi-ty to GW2 which is known,and there exists a single nucleotide change at site 1 14 without the variation in amino acid. Comparing with GW2 in TD70,the gene in Kasalath express the intact protein without advanced stop.For GW2 gene, the dCAPS marker was designed according to a base deletion of A in the 3 1 6 site of sequence.Digested by Apo I,TD70 showed 21 bp and 30 bp fragments and Kasalath showed 5 1 bp fragment.Among the 240 RILs,82 contained GW2 TD70 and 1 58 contain GW2 Kasalath ,there are significant differences between their phenotypic value.No GW2 TD70 gene exit in 10 japonica rice cultivars from Jiangsu Province and 8 indica restorer lines.GW2 gene derived from TD70 may have regula-tory effects on grain width,and we can use it to improve grain weight in rice breeding.

关 键 词：水稻 极端粒形 GW2基因 序列分析 粒形 

分 类 号：S511[农业科学—作物学]