Genetic mechanism controlling the transportation and accumulation of glutelin into protein body in rice endosperm

控制水稻胚乳中谷蛋白向蛋白体转运和积累的遗传机制

基本信息

批准号：
12138206
负责人：
SATOH Hikaru
金额：
$ 24.51万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2003
项目状态：
已结题

项目摘要

To elucidate the mechanism of intracellular transportation and accumulation of rice seed storage protein, 130 Iines of 57H mutant, which are characterized by the increased amount of proglutelin with 57 kD, were produced and novel 4 genes for 57H trait were identified. Based on genetic and histochemical analyses of the mutants, the function of each gene was discussed.-Mutation for the sorting of storage proteins within endoplasmic reticulum (ER), Type1 mutation The analysis of esp2 mutation deleted PDI demonstrated that PDI was indispensable for the sorting of proglutelin precursor and prolamin within ER Iumen. glup4 and glup6 mutations also were classified into Type1 mutation, showing that at least 3 genes participate in the sorting of both proteins within ER lumen.-Mutation for transportation from ER to protein storage vacuole (PSV), Type2 mutation In Type2 mutation, proglutelin precursor and prolamin were accumulated into separated particles within ER derived PB. Glup1, glup2, Glup5, glup7, Glup8 mutations were classified into Type2 mutation, showing that at least 5 genes participate in the transportation of proglutelin from ER lumen to PSV.-Mutation for proteolysis within PSV. Type3 mutation The analysis of glup3 mutation demonstrated that VPE was indispensable for proteolytical cleavage of proglutelin precursor within PSV. glup3 mutation accumulated the progiutelin and the cleaved form of glutelin in PSV together, showing that at least 2 VPEs participate in proteolysis of proglutelin precursor.These results demonstrated that the pathway of transportation and accumulation of glutelin in seed was divided into steps and that the genes regulating each step were 1) Targeting of glutelin mRNA to cis-ER, 2) Sorting of proglutelin precursor within ER lumen, Esp2 (PDI), Glup4, Glup6, 3) Transportation of proglutelin precursor into PSV, glupl, Glup2, glup5, Glup7, glup8, 4) Proteolysis of proglutelin precursor within PSV, Glup3 (VPE),

为了阐明水稻种子贮藏蛋白的细胞内运输和积累的机制，产生了130个57H突变体系，其特征是57kD的前谷蛋白含量增加，并鉴定了57H性状的4个新基因。基于对突变体的遗传和组织化学分析，讨论了每个基因的功能。-内质网（ER）内储存蛋白分选的突变，Type1突变对esp2突变删除PDI的分析表明PDI对于分选是必不可少的ER 腔内的谷蛋白前体和谷醇溶蛋白的含量。 glup4 和 glup6 突变也被分类为 1 型突变，表明至少有 3 个基因参与 ER 腔内两种蛋白质的分选。-从 ER 运输到蛋白质储存液泡 (PSV) 的突变，2 型突变在 2 型突变中，谷蛋白前体和谷醇溶蛋白在ER衍生的PB内积累成分离的颗粒。 Glup1、glup2、Glup5、glup7、Glup8突变被归类为2型突变，表明至少有5个基因参与了谷蛋白原从ER腔到PSV的运输。-PSV内蛋白水解的突变。 3 型突变 glup3 突变分析表明，VPE 对于 PSV 内谷蛋白原前体的蛋白水解裂解是不可缺少的。 glup3突变将PSV中的谷蛋白原和裂解形式的谷蛋白一起积累，表明至少有2个VPE参与谷蛋白原前体的蛋白水解。这些结果表明种子中谷蛋白的运输和积累途径分为多个步骤，并且基因调节每个步骤是 1) 谷蛋白 mRNA 靶向 cis-ER，2) ER 腔内谷蛋白前体的分选，Esp2 (PDI)、Glup4、Glup6、3) 将谷蛋白原前体转运至 PSV、glup1、Glup2、glup5、Glup7、glup8、4) PSV 内谷蛋白原前体的蛋白水解、Glup3 (VPE)、