水稻赤霉素类受体基因OsGRL1调控水稻穗外露及籽粒大小的功能分析  

Functional analysis of rice gibberellin receptor like gene OsGRL1 in regulating panicle exsertion and grain size in rice

作　　者：杨晓颖 胡又川 杨淇 孙丽娜 徐汉琴 庞梦真 宁晓彤 黄诗雨 梁闪闪[1,2] 张泗举[1,2] 栾维江[1,2] YANG XiaoYing;HU YouChuan;YANG Qi;SUN LiNa;U HanQin;PANG MengZhen;NING XiaoTong;HUANG ShiYu;LIANG ShanShan;ZHANG SiJu;LUAN WeiJiang(College of Life Sciences,Tianjin Normal University,Tianjin 300387,China;Tianjin Key Laboratory of Animal and Plant Resistance,Tianjin Normal University,Tianjin 300387,China)

机构地区：[1]天津师范大学生命科学学院,天津300387 [2]天津师范大学天津市动植物抗性重点实验室,天津300387

出　　处：《中国科学：生命科学》2023年第9期1310-1323,共14页Scientia Sinica(Vitae)

基　　金：国家自然科学基金(批准号:31770343);天津市水稻产业技术体系创新团队项目(ITTRRS2021100004)资助。

摘　　要：穗的外露(穗颈长度)对水稻的产量有重要影响.穗颈过短,会造成包颈穗,影响水稻的结实率;穗颈过长,容易造成倒伏或穗颈折断,从而影响水稻的生产和产量.赤霉素(gibberellin,GA)在植物茎的伸长调控中起着重要作用.本研究对水稻赤霉素类受体家族基因OsGRL1(Gibberellin receptor like 1)的功能进行了探究,发现该基因在水稻穗颈长度和产量性状方面具有重要的调控作用.表达分析表明,OsGRL1在茎、叶鞘及茎顶端组织中高表达,不受外源GA的诱导.亚细胞定位分析表明,与已知的水稻GA受体蛋白OsGID1定位于细胞核中不同,OsGRL1蛋白定位在细胞膜上,且不随外源GA的诱导而改变.与野生型相比,OsGRL1敲除突变体表现出穗颈伸长、籽粒变小和千粒重降低的表型,而过表达转基因株系穗颈缩短、籽粒变大且千粒重增加.进一步研究发现,OsGRL1基因突变使GA信号转导通路中抑制基因SLR1的表达下调,提高了突变体对GA敏感性.因此,OsGRL1通过调控GA信号转导通路基因的表达而调节水稻穗颈伸长和产量,在育种中具有潜在的应用价值.In rice,the length of the panicle exsertion has an important impact on yield.Shorter panicle exsertions lead to wrapped panicles and affect the seed setting rate,while longer panicle exsertions lead to lodging or broken necks,which affects the production and yield of rice.Gibberellin(GA)plays an important role in the regulation of plant stem elongation.In this study,we analyzed a gibberellin receptor like family member,OsGRLI(Gibberellin receptor like I),and demonstrated that it played important roles in the regulation of panicle exsertions and yield traits in rice.OsGRLI was highly expressed in stems,leaf sheaths and shoot apical meristems,and the expression of OsGRL1 was not induced by exogenous GA.Unlike nuclear localization pattern of known GA receptor OsGIDI,OsGRL1 protein was localized on the cell membrane,no matter in the presence or absence of exogenous GA.Compared to the wild type,osgrll mutants displayed the phenotypes with the elongated panicle exsertion,smaller grains and reduced 1000-grains weight,while the overexpression lines displayed shorter panicle exsertion,larger grains and increased 1000-grains weight.Further experiments showed that the knockout of OsGRL1 down-regulated the expression of SLRI,a suppressor in the GA signal transduction pathway,thereby making the mutant more sensitive to GA.Taken together,OsGRLI regulates panicle exsertion and yield by regulating the expression of genes involved in GA signal transduction pathway,which has potential applications in rice breeding.

关 键 词：水稻 赤霉素类受体家族 赤霉素 穗外露 

分 类 号：S511[农业科学—作物学]