DMT1编码一个丝氨酸/半胱氨酸蛋白酶调控水稻分蘖并参与干旱胁迫响应  

DMTI encodes a serine/cysteine protease that regulates rice tillering and participates in drought stress response

作　　者：芦涛 殷文晶 戴若惠 陈振概 沈芷琦 叶涵斐 杨丽君 严钢 吴思思 何瑞 张琪 李三峰 王跃星 饶玉春[1] LU Tao;YIN WenJing;DAI RuoHui;CHEN ZhenGai;SHEN ZhiQi;YE HanFei;YANG Lijun;YAN Gang;Wu Sisi;HE Rui;ZHANG Qi;LI SanFeng;WANG YueXing;RAO YuChun(College of Chemistry and Life Sciences,Zhejiang Normal University,Jinhua 321004,China;State Key Laboratory of Rice Biology,China National Rice Research Institute,Hangzhou 310006,China;Zhejiang Jinhua Ecological and Environmental Monitoring Center,Jinhua 321004,China)

机构地区：[1]浙江师范大学化学与生命科学学院,金华321004 [2]中国水稻研究所,水稻生物学国家重点实验室,杭州310006 [3]浙江金华生态环境监测中心,金华321004

出　　处：《中国科学：生命科学》2023年第4期529-542,共14页Scientia Sinica(Vitae)

基　　金：国家科技重大专项子课题(批准号:2016ZX08009003-003-008);国家自然科学基金(批准号:U20A2030,31971921);中国水稻生物学国家重点实验室开放项目(批准号:20200102)资助。

摘　　要：水稻分蘖的形成是一个复杂的过程,受到环境及遗传因素的影响,合适的分蘖可以显著提高水稻产量.本研究利用甲基磺酸乙酯(ethyl methanesulfonate, EMS)诱变粳稻秀水11得到一份矮化、多分蘖突变体,将其命名为dwarf and multiple tillers 1(dmt1),并对其进行表型观察,生理生化分析,遗传分析,基因定位和激素处理.结果发现,在dmt1在分蘖期出现株高变矮,叶片面积变小,分蘖数增多等特征.遗传分析表明,该dmt1为单隐性核基因控制,图位克隆的结果显示, DMT1位于第4染色体上,编码一个丝氨酸/半胱氨酸蛋白酶,是NAL1的等位基因.亚细胞定位的结果表明, DMT1蛋白在细胞核、细胞质和叶绿体上均有表达.为探究该基因突变是否会影响水稻对激素的敏感程度,本研究通过施加外源激素发现dmt1地上部分对NAA敏感程度降低,而地下部分对于GA3敏感程度升高.并且在dmt1中生长素合成相关基因表达量降低.通过干旱处理发现dmt1的耐旱能力下降,在干旱胁迫下dmt1的发芽率降低.由实验可得, DMT1突变会导致植株产生株高变矮,分蘖增多的表型,通过qRT-PCR发现可能是由于生长素合成障碍引起的表型.这为研究水稻分蘖机制的遗传网络提供了新的信息.The formation of rice tillers is a complicated process.It is affected by environmental and genetic factors.Proper tillers can significantly increase rice yield.In this study,ethyl methanesulfonate(EMS)was used to mutate japonica rice Xiushui 1l to obtain a dwarf,multi-tillering mutant,named dwarf and multiple tillers I(dmtl),and performed phenotypic observation,physiological and biochemical analysis,genetic analysis,gene mapping and hormone treatment.It was found that dmtl had plant height changes at the tillering stage shorter,smaller leaf area,increased tiller number and other characteristics.Genetic analysis shows that the dmtl is controlled by a single recessive nuclear gene.The results of map-based cloning show that DMT1 is located on chromosome 4 and encodes a serine/cysteine protease and is an allele of NALI.The results of cell localization show that DMT1 protein is expressed in the nucleus,cytoplasm,and chloroplasts.In order to explore whether this gene mutation will affect the sensitivity of rice to hormones,we found that the aboveground parts of dmtl are less sensitive to NAA by applying exogenous hormones.The underground part is more sensitive to GAg.And the expression of genes related to auxin synthesis in dmt1 is reduced.Through drought treatment,it is found that the drought tolerance of dmtl is reduced,and the germination rate of dmtl is reduced under drought stress.DMTI can be obtained from the experiment.Mutations can cause plants to produce phenotypes with shorter plant heights and increased tillers.The phenotypes may be caused by auxin synthesis disorders through qRT-PCR.This provides new information for the genetic network of rice tillering mechanisms.

关 键 词：水稻 分蘖 遗传分析 DMT1 外源激素 干旱处理 

分 类 号：S511[农业科学—作物学]