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

类囊体中的F1Fo-ATP合成酶将ATP合成与光驱动的电化学质子梯度偶联。F1Fo-ATP合成酶是一种无辅助因子的多蛋白复合物，由跨膜结构域（CFo）和外周结构域（CF1）组成。对类囊体ATP合酶的形成知之甚少，迄今为止只有少数组装因子被表征。在之前的工作中，我们在拟南芥中鉴定出了类囊体整合蛋白CGL160 (AtCGL160)，这是高效的CFo组装所必需的。AtCGL160包含两个结构域；一个是植物特异性结构域，另一个是与蓝藻蛋白Atp1有远亲关系的结构域。此外，我们可以在拟南芥中鉴定出一个新的假定的类囊体ATP合成酶组装因子：AtHTN1。本子项目的目的是在分子水平上破译AtHTN1和植物特异性AtCGL160结构域在ATP合酶组装中的功能。我们还将扩展我们的研究到Atp1在聚囊藻中的功能表征，并通过遗传学，生化和电子显微镜方法分析其在蓝藻ATP合成酶组装过程中的作用。我们的长期目标是阐明构建功能性类囊体ATP合酶所需的整个辅助因子的相互作用，确定其作用模式并揭示其功能的演变。

F1Fo-ATP synthases in thylakoids couple ATP synthesis to the light-driven electrochemical proton gradient. F1Fo-ATP synthases are cofactor-free multiprotein complexes and consist of a membrane-spanning (CFo) and a peripheral domain (CF1). Relatively little is known about thylakoid ATP synthase formation and only few assembly factors have been characterized so far. In previous work we could identify the thylakoid integral protein CGL160 in Arabidopsis (AtCGL160), which is required for efficient CFo assembly. AtCGL160 contains two domains; a plant-specific domain and a second domain which is distantly related to the cyanobacterial protein Atp1. Moreover, we could identify an additional novel putative thylakoid ATP synthase assembly factor in Arabidopsis: AtHTN1. The objective of this subproject is to decipher the function of AtHTN1 and of the plant-specific AtCGL160 domain in ATP synthase assembly at the molecular level. We will also extend our study to the functional characterization of Atp1 in Synechocystis and analyze its role in the cyanobacterial ATP synthase assembly process by genetic, biochemical and electron microscopy approaches. Our long-term goal is to elucidate the interplay of the entire ensemble of auxiliary factors necessary to construct a functional thylakoid ATP synthase, to determine their mode of action and to unravel the evolution of their function(s).