PDF(Pubmed)
Abstract：
While the molecular mechanism of autophagy is well studied, the cargoes delivered by autophagy remain incompletely characterized. To examine the selectivity of autophagy cargo, we conducted proteomics on isolated yeast autophagic bodies, which are intermediate structures in the autophagy process. We identify a protein, Hab1, that is highly preferentially delivered to vacuoles. The N-terminal 42 amino acid region of Hab1 contains an amphipathic helix and an Atg8-family interacting motif, both of which are necessary and sufficient for the preferential delivery of Hab1 by autophagy. We find that fusion of this region with a cytosolic protein results in preferential delivery of this protein to the vacuole. Furthermore, attachment of this region to an organelle allows for autophagic delivery in a manner independent of canonical autophagy receptor or scaffold proteins. We propose a novel mode of selective autophagy in which a receptor, in this case Hab1, binds directly to forming isolation membranes during bulk autophagy.
摘要：
虽然自噬的分子机制得到了很好的研究，通过自噬递送的货物仍未完全表征。为了检查自噬货物的选择性，我们对分离的酵母自噬体进行了蛋白质组学，它们是自噬过程中的中间结构。我们鉴定了一种蛋白质,Hab1，高度优先输送到液泡。Hab1的N端42个氨基酸区域包含两亲性螺旋和Atg8家族相互作用基序，这两者对于通过自噬优先递送Hab1是必要和充分的。我们发现该区域与胞质蛋白的融合导致该蛋白优先递送至液泡。此外，该区域与细胞器的连接允许以独立于经典自噬受体或支架蛋白的方式进行自噬递送。我们提出了一种选择性自噬的新模式，其中一个受体，在这种情况下，Hab1在大量自噬过程中直接与形成的分离膜结合。
