Mechanisms and functions of protein S-acylation modifications at the plant vacuolar membrane

蛋白质的S酰化是一种重要的二次修饰，调节蛋白质膜的结合、靶向性和功能。然而，由于修饰酶对靶蛋白的功能冗余，对修饰蛋白S-酰基转移酶(PATS)和修饰的靶蛋白的详细生化和遗传分析一直受到阻碍。在植物中，蛋白质S酰化的机制、功能和要求还不是很清楚。因此，我们采用了功能筛选的方法，从拟南芥中鉴定出一对特定的酶-底物对(PAT10-CBL2)，它现在可以直接在植物液泡膜上研究脂类修饰的机制。因此，本项目旨在阐明拟南芥PAT蛋白10和11的功能特性，它们代表液泡膜定位的酶。此外，我们还将分析靶向酶(PAT)及其底物所需的机制原理，特别是空泡PAT酶对液泡膜结合的钙调神经磷酸酶(CBL)等底物的特定修饰。

Protein S-acylation is an important secondary modification and regulates protein membrane association, targeting and function. However, detailed biochemical and genetic analyses of the modifying protein S-acyltransferases (PATs) and of modified target proteins have been hampered by the functional redundancy of modifying enzymes towards targets. In plants, the mechanisms, functions and requirements for protein S-acylation are not well understood. Therefore, we employed a functional screen and identified a specific enzyme-substrate pair (PAT10-CBL2) from Arabidopsis thaliana, which now allows addressing the mechanism of lipid modification at the plant tonoplast directly. Consequently, this project aims to elucidate the functional properties of the PAT proteins 10 and 11 from Arabidopsis, representing tonoplast localized enzymes. In addition we will analyze the mechanistic principles required for the targeting of enzymes (PAT) as well as their substrates, and especially the specific modification of substrates like the tonoplast bound calcineurin B-like (CBL) proteins by the vacuolar PAT enzymes.