Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo, Japan.
FEBS J. 2012 Apr;279(8):1407-13. doi: 10.1111/j.1742-4658.2012.08548.x. Epub 2012 Mar 23.
The four protein complexes termed endosomal sorting complexes required for transport (ESCRT) are key mediators of multivesicular body sorting/formation, retroviral budding and cell abscission, which share a membrane deformation process with the same topological change: vesicles budding away from the cytoplasm. Independent studies of the signal transduction pathways that mediate ambient pH sensing and adaptation in yeast and fungi revealed that these pathways share a conserved signaling mechanism that utilizes ESCRT complexes for its activation. This pathway in Saccharomyces cerevisiae, termed the Rim101 pathway, consists of both a sensing complex, which senses ambient alkaline pH, and a proteolytic complex, which proteolyzes and thereby activates the key transcription factor Rim101. Since the proteolytic complex is thought to be formed and activated on a platform of a multimerized ESCRT-III component Snf7, the organization, regulation and function of this pathway are dependent on the function of ESCRT complexes.
这四个被称为内体分选复合物所需的蛋白质复合物（ESCRT）是多泡体分选/形成、逆转录病毒出芽和细胞分裂的关键介质，它们与相同的拓扑变化共享一个膜变形过程：小泡从细胞质中分离出来。对介导酵母和真菌中环境 pH 感应和适应的信号转导途径的独立研究表明，这些途径共享一个保守的信号机制，利用 ESCRT 复合物来激活该信号机制。在酿酒酵母中，这种途径被称为 Rim101 途径，它由一个感应复合物组成，该复合物感应环境碱性 pH，以及一个蛋白水解复合物，该复合物蛋白水解并激活关键转录因子 Rim101。由于蛋白水解复合物被认为是在 Snf7 的多聚 ESCRT-III 组分的平台上形成和激活的，因此该途径的组织、调节和功能依赖于 ESCRT 复合物的功能。
