Studies on Molecular Basis for Reactive Nitrogen Metabolism in Plants

植物活性氮代谢的分子基础研究

基本信息

批准号：
15570038
负责人：
SAKAMOTO Atsushi
金额：
$ 2.24万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

项目摘要

(1)Arabidopsis 2-Cys Peroxiredoxin as Metabolic Enzyme for Reactive Nitrogen SpeciesPurified recombinant proteins of a thiol-dependent peroxidase called 2-Cys peroxiredoxin (2CPRX) from Arabidopsis were shown to metabolically scavenge peroxynitrite, a reactive nitrogen species (RNS) known as a potent oxidizing and nitrating agent. The Arabidopsis 2CPRX cDNA was functionally able to complement the hypersensitivity of a yeast mutant to nitrite-derived RNS. These results demonstrated a new role of plant 2CPRX as a critical determinant of the resistance to RNS, and support the existence of a plant enzymatic basis for RNS metabolism.(2)Functional relevance of Arabidopsis Non-Symbiotic Hemoglobin to Reactive Nitrogen SpeciesPlants ubiquitously contain non-symbiotic hemoglobins whose physiological role remains obscure. Purified recombinant proteins of an Arabidopsis non-symbiotic hemoglobin (AtGLB1) were shown to possess peroxidase-like activity that can oxidize nitrite as electron donor to f … More orm nitrogen dioxide radicals. AtGLB1 mRNA significantly accumulated in Arabidopsis seedlings that had been exposed to nitrite. These results support the physiological relevance of the function of AtGLB1 to nitrite and nitrite-derived RNS, and suggest a new possible route for RNS production in plants, apart from nitric-oxide (NO) biogenesis.(3)Plant-Physiological Impact of Molecular-Genetic Alteration in S-Nitrosothiol MetabolismS-Nitrosothiols (RSNO), a major form of RNS, are NO-adducts of thiol compounds such as S-nitrosoglutathione (GSNO) that is a representative RSNO with biological relevance. Overexpression of Arabidopsis GSNO reductase (GSNOR), the only known plant enzyme possibly involved in RSNO metabolism, led to a significant RSNO reduction in transgenic Arabidopsis. In contrast, knocking out the GSNOR gene resulted in RSNO over-accumulation. Metabolic studies of NO_2 assimilation in transgenic Arabidopsis overexpressing GSNOR suggested the existence of a crosstalk between RNS metabolism and the primary nitrogen assimilation. These results strongly indicate GSNOR as a key enzyme in RSNO metabolism and its potential importance in plant nitrogen metabolism. Less

(1) 拟南芥 2-Cys 过氧化还原蛋白作为活性氮物质的代谢酶来自拟南芥的硫醇依赖性过氧化物酶（称为 2-Cys 过氧化还原蛋白 (2CPRX)）的纯化重组蛋白可以代谢清除过氧亚硝酸盐，过氧化亚硝酸盐是一种活性氮物质 (RNS)，称为拟南芥的强氧化剂和硝化剂。 2CPRX cDNA 在功能上能够证明酵母突变体对亚硝酸盐衍生的 RNS 过敏。这些结果表明植物 2CPRX 作为 RNS 抗性的关键决定因素，并支持 RNS 代谢的植物酶学基础的存在。 2）拟南芥非共生血红蛋白与活性氮物种的功能相关性植物普遍含有非共生血红蛋白拟南芥非共生血红蛋白 (AtGLB1) 的纯化重组蛋白具有类似过氧化物酶的活性，可以将亚硝酸盐作为电子供体氧化成在拟南芥中显着积累的二氧化氮自由基。这些结果支持 AtGLB1 功能与亚硝酸盐和亚硝酸盐的生理相关性。亚硝酸盐衍生的 RNS，并提出了除一氧化氮 (NO) 生物发生之外的植物中 RNS 生产的新可能途径。(3) S-亚硝基硫醇代谢中分子遗传改变的植物生理影响S-亚硝基硫醇 (RSNO)， RNS 的主要形式是硫醇化合物的 NO 加合物，例如 S-亚硝基谷胱甘肽 (GSNO)，它是代表性的 RSNO拟南芥 GSNO 还原酶（GSNOR）是唯一已知的可能参与 RSNO 代谢的植物酶，其过度表达会导致转基因拟南芥中 RSNO 显着减少，相反，敲除 GSNOR 基因会导致 RSNO 代谢过度积累。对过表达GSNOR的转基因拟南芥中NO_2同化的研究表明，RNS代谢与初级氮同化之间存在串扰。这些结果强烈表明 GSNOR 作为 RSNO 代谢的关键酶及其在植物氮代谢中的潜在重要性。

项目成果

期刊论文数量（94）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Three distinct Arabidopsis hemoglobins exhibit peroxidase-like activity and differentially mediate nitrite-dependent protein nitration

DOI：
10.1016/j.febslet.2004.07.005
发表时间：
2004-08-13
期刊：
FEBS LETTERS
影响因子：
3.5
作者：
Sakamoto, A;Sakurao, S;Morikawa, H
通讯作者：
Morikawa, H

Morikawa et al.: "Formation of unidentified nitrogen in plants : an implication for a novel nitrogen metabolism"Planta. (印刷中). (2004)

Morikawa 等人：“植物中未知氮的形成：对新型氮代谢的影响”Planta（出版中）。

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

Phytoremediators from abandoned rice field.

来自废弃稻田的植物修复剂。

DOI：
发表时间：
2005
期刊：
Plant Biotechnology 22
影响因子：
0
作者：
Takahashi et al.;Morikawa et al.;Morikawa et al.;Kurumata et al.;Takahashi et al.
通讯作者：
Takahashi et al.

Genetic engineering of cold-tolerant tomato via glycinebetaine biosynthesis.

通过甘氨酸甜菜碱生物合成的耐寒番茄基因工程。