Molecular mechanisms of the microbody transition in higher plants

高等植物微体转变的分子机制

• 批准号: 12440231
• 负责人: NISHIMURA Mikio
• 金额: $ 9.54万
• 依托单位: Okazaki National Research Institutes
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12440231/
• 关键词: microbody; integral membrane protein; ATP; ADP carrier protein; Arabidopsis thaliana; protein traffic; glyoxysomes; leaf peroxisomes; targeting signal; アスコルビン酸ペルオキシダーゼ; 小胞体; マイクロボディ移行配列; ペルオキシソーム; グリオキシソーム; 光呼吸

In order to clarify the microbody transition in higher plants, we have analyzed the development of microbody membrane proteins and arabidopsis mutants that defects on fatty acid *** -oxidation. We characterized one of the major microbody membrane proteins, PMP38. The deduced amino acid sequence for its cDNA in Arabidopsis thalia na contained polypeptides with 331 amino acids and had high similarity with those of Homo sapiens PMP34 and Candida boidinll PMP47 known as homologues of mitochondrial ATP/ADP carrier protein. Cell fractionation and immunocytochemical analysis using pumpkin cotyledons revealed that PMP38 is localized on microbody membranes as an integralmembrane protein. The amount of PMP38 in pumpkin cotyledons increased and reached the maximum protein level after 6 d in the dark but decreased thereafter. Illumination of the seedlings caused a significant decrease in the amount of the proteinThese results clearly showed that themembrane protein PMP38 in glyoxysomes changes dra … More matically during the transformation of glyoxysomes to leaf peroxisomes, as do the other glyoxysomal enzymes, especially enzymes of the fatty acid *** -oxidation cycle, that are localized in the matrix of glyoxysomes. We previously isolated an Arabidopsis peroxisomedeficient ped2 mutant by its resistance to 2, 4-dichlorophenoxybutyric acid. We describe the isolation of a gene responsible for this deficiency, called the PED2 gene, by positional cloning and confirmed its identity by complementation analysis. The amino acid sequence of the predicted protein product is similar to that of human Pex14p, which is a key component of the microbody protein import machinery. Therefore, we decided to call it AtPex14p. Analyzes of the ped2 mutant revealed that AtPex14p controls intracellular transport of both peroxisome targeting signal (PTS)1 and PTS2-containing proteins into three different types of microbodies, namely glyoxysomes, leaf peroxisomes and unspecialized peroxisomes. Mutation in the PED2 gene results in reduction of enzymes in all of these functionally differentiated microbodies. The reduction in these enzymes induces pleiotropic defects, such as fatty acid degradation, photorespiration and the morphology of microbodies. We also identified PED3 gene as a full-size ATP-binding cassette transporter. The studies on the microbody transition in these mutants are now in progress. Less

为了阐明高等植物中微体的转变，我们分析了微体膜蛋白和脂肪酸氧化缺陷突变体的发育情况。我们鉴定了主要的微体膜蛋白之一PMP38。其推导的氨基酸序列由331个氨基酸组成，与线粒体ATP/ADP载体蛋白的同源物智人PMP34和假丝酵母PMP47有很高的相似性。细胞分级和南瓜子叶免疫细胞化学分析表明，PMP38以整膜蛋白的形式定位在微体膜上。在黑暗条件下，南瓜子叶中PMP38的含量增加，在6d后达到最大蛋白水平，之后又下降。光照使幼苗中蛋白质的含量显著减少。这一结果清楚地表明，乙氧体中的膜蛋白PMP38改变了DRA…更容易的是，在乙氧基体转化为叶片过氧化体的过程中，其他乙氧基体酶也是如此，特别是位于乙氧基体基质中的脂肪酸氧化循环中的酶。我们先前通过对2，4-二氯苯氧基丁酸的抗性分离到了一个缺乏过氧化物酶的突变体pe2。我们描述了通过定位克隆分离导致这种缺陷的一个基因，称为PED2基因，并通过互补分析确认了它的身份。预测的蛋白质产物的氨基酸序列与人Pex14p的氨基酸序列相似，Pex14p是微体蛋白质输入机制的关键组成部分。因此，我们决定将其命名为AtPex14p。对Ped2突变体的分析表明，AtPex14p控制着过氧化体靶向信号(PTS)1和含有PTS2的蛋白质在细胞内的运输，这些微体是三种不同类型的微体，即乙氧基体、叶片过氧体和非特化的过氧体。PED2基因的突变导致所有这些功能分化的微体中的酶减少。这些酶的减少会导致多效性缺陷，如脂肪酸降解、光呼吸和微体的形态。我们还鉴定了PED3基因是一个全长的三磷酸腺苷结合盒转运体。对这些突变体的微体转变的研究正在进行中。较少

项目成果

Hayashi, M., K. Nito, R. Takei-Hoshi, M. Yagi, M. Kondo, A. Suenaga, T. Yamaya, and M. Nishimura: "Ped3 is a peroxisomal ATP-binding cassette transporter that mighi supply susstrates for fatty acid β-oxidation."Plant Cell Physiol. 43. 1-11 (2002)

Hayashi, M.、K. Nito、R. Takei-Hoshi、M. Yagi、M. Kondo、A. Suenaga、T. Yamaya 和 M. Nishimura：“Ped3 是一种过氧化物酶体 ATP 结合盒转运蛋白，可能提供维持用于脂肪酸β-氧化。“植物细胞生理学. 43. 1-11 (2002)

Yasuko Hayashi: "Direct interaction between glyoxysomes and lipid bodies in etiolated cotyledons of Arabidopsis thaliana ped1 mutant"Protoplasma. 218. 83-94 (2001)

Yasuko Hayashi：“拟南芥 ped1 突变体黄化子叶中乙醛酸体和脂质体之间的直接相互作用”原生质体。

Hayashi, M. et al.: "Ped 3p is a peroxisomal ATP-binding cassete transporter that might supply substrates for fatty acid β-oxidation"Plant Cell Physiol..

Hayashi, M. 等人：“Ped 3p 是一种过氧化物酶体 ATP 结合盒转运蛋白，可能是脂肪酸 β-氧化的底物供应”植物细胞生理学..

Hayashi, Y., M. Hayashi., H. Hayashi, I Hara-Nishimura and M. Nishimura: "Direct interaction between glyoxysomes and lipid bodies in cotyledons of the Arabidopsis thalianapedl mutant."Protoplasma,. 218. 83-94 (2001)

Hayashi, Y.、M. Hayashi.、H. Hayashi、I Hara-Nishimura 和 M. Nishimura：“拟南芥突变体子叶中乙醛酸体和脂质体之间的直接相互作用。”原生质体，。

Makoto Hayashi: "Ped 3p is a peroxisomal ATP-binding cassete transporter that might supply substrates for fatty acid β-oxidation"Plant Cell Physiol.. 43. 1-11 (2002)

Makoto Hayashi：“Ped 3p 是一种过氧化物酶体 ATP 结合盒转运蛋白，可能为脂肪酸 β-氧化提供底物”Plant Cell Physiol.. 43. 1-11 (2002)