Auxiliary factors required for the accumulation and functioning of the thylakoid ATP synthase

类囊体 ATP 合酶积累和发挥作用所需的辅助因子

• 批准号: 261977268
• 负责人: Professor Dr. Dario Leister
• 金额: --
• 依托单位: Lehrstuhl für Molekularbiologie der Pflanzen
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/261977268?language=en
• 关键词: Auxiliary; factors; required; accumulation; functioning

The chloroplast F1Fo-ATP synthase (cpATPase) couples ATP synthesis to the light-driven electrochemical proton gradient and comprise two parts, the membranous CFo subcomplex that is a proton channel and the peripheral CF1 subcomplex that contains the catalytic sites for reversible ATP synthesis. To fully assemble a functional cpATPase complex, various auxiliary factors are needed - either for the expression of the chloroplast-located genes for cpATPase subunits (the atp genes) or for the assembly process itself. While several assembly factors of the F1Fo-ATP synthase are known in prokaryotes and yeast, for plants only the assembly factor ALB4 has been identified yet. In addition, a couple of plant proteins involved in atp gene expression have been described. In this project, we want to characterize two novel auxiliary proteins required for cpATPase biogenesis in the model plant Arabidopsis thaliana. The first one, AtCGL160, appears to be a true assembly factor and interacts physically with subunits of the CFo subcomplex. Interestingly, AtCGL160 contains besides a plant-specific domain also a shorter part, which is related to the prokaryotic Atp1/UncI proteins that have been also brought into connection with ATP synthase assembly. Therefore, we want to clarify the mechanism by which AtCGL160 promotes cpATPase assembly, whether this mechanism is conserved between prokaryotic Atp1/UncI proteins and eukaryotic CGL160 proteins, and reveal the function of the plant-specific part of AtCGL160. The second protein that we have identified to be required for cpATPase biogenesis is AtCGLD11. In contrast to AtCGL160, the AtCGLD11 protein is soluble and displays an mRNA expression pattern that suggests a function in atp gene expression. Therefore, we will characterise the function(s) of AtCGLD11 particularly in atp gene expression, including global approaches that can detect its interactions with any of the entire set of chloroplast genes and transcripts.

叶绿体 F1Fo-ATP 合酶 (cpATPase) 将 ATP 合成与光驱动的电化学质子梯度耦合，并由两部分组成：作为质子通道的膜 CFo 亚复合物和包含可逆 ATP 合成催化位点的外围 CF1 亚复合物。为了完全组装功能性 cpATP 酶复合物，需要各种辅助因子 - 要么用于 cpATP 酶亚基位于叶绿体的基因（atp 基因）的表达，要么用于组装过程本身。虽然原核生物和酵母中已知 F1Fo-ATP 合酶的多个组装因子，但对于植物，仅鉴定了组装因子 ALB4。此外，还描述了一些参与 atp 基因表达的植物蛋白。在这个项目中，我们想要表征模式植物拟南芥中 cpATP 酶生物发生所需的两种新型辅助蛋白。第一个 AtCGL160 似乎是真正的组装因子，并与 CFo 子复合物的亚基发生物理相互作用。有趣的是，AtCGL160 除了植物特异性结构域外，还包含一个较短的部分，该部分与原核 Atp1/UncI 蛋白有关，这些蛋白也与 ATP 合酶组装有关。因此，我们希望阐明AtCGL160促进cpATPase组装的机制，该机制在原核Atp1/UncI蛋白和真核CGL160蛋白之间是否保守，并揭示AtCGL160植物特异性部分的功能。我们已经确定 cpATPase 生物发生所需的第二种蛋白质是 AtCGLD11。与 AtCGL160 相比，AtCGLD11 蛋白是可溶的，并显示出 mRNA 表达模式，表明其在 atp 基因表达中发挥作用。因此，我们将描述 AtCGLD11 的功能，特别是 atp 基因表达中的功能，包括可以检测其与整套叶绿体基因和转录本中任何一个的相互作用的全局方法。