Role of multifunctional proteins in biogenesis, metabolism and regulation of the mitochondrial outer membrane

线粒体外膜将线粒体与其他细胞区室连接起来，在代谢、蛋白质和脂质生物发生、膜动力学、信号传导和质量控制等方面发挥着至关重要的作用。外膜包含大约80种不同的蛋白质，这就提出了一个问题，即如何通过这有限的一组蛋白质来执行和协调众多的任务。通过分析外膜蛋白前转位网络，我们观察到具有多种功能的蛋白质数量出乎意料地高。为了验证多功能蛋白发挥核心作用的假设，我们将在模式生物面包酵母中定义线粒体外膜的综合蛋白质相互作用网络。与至少两个不同的伙伴相互作用的蛋白质将受到分子解剖，以定义不同的功能，并确定功能状态之间切换的机制。我们预计至少在以下类别中有双重功能分配：蛋白质易位和组装，代谢物转移，脂质代谢，膜结构和调节过程。我们的目标是了解线粒体外膜蛋白网络的分子机制和功能组织，从而为定义整个膜系统中多功能蛋白的重要性建立一个范例。

The mitochondrial outer membrane links mitochondria to other cellular compartments and performs crucial functions in metabolism, protein and lipid biogenesis, membrane dynamics, signaling and quality control. The outer membrane contains about 80 different proteins, raising the question how the numerous tasks can be performed and coordinated by this limited set of proteins. By analyzingthe network of outer membrane preprotein translocases, we observed an unexpectedly high number of proteins that perform more than one function. To test our hypothesis that multifunctional proteins play a central role, we will define a comprehensive protein interaction network of the mitochondrial outer membrane in the model organism baker’s yeast. Proteins interacting with atleast two different partners will be subjected to a molecular dissection to define distinct functions and to identify mechanisms for switching between functional states. We expect dual functional assignments at least in the following categories: protein translocation & assembly, metabolite transfer, lipid metabolism, membrane architecture, and regulatory processes. Our goal is tounderstand the molecular mechanisms and functional organization of the mitochondrial outer membrane protein network, thus establishing a paradigm for defining the importance of multifunctional proteins in an entire membrane system.