Membrane recruitment of Aut7p in the autophagy and cytoplasm to vacuole targeting pathways requires Aut1p, Aut2p, and the autophagy conjugation complex.
Membrane recruitment of Aut7p in the autophagy and cytoplasm to vacuole targeting pathways requires Aut1p, Aut2p, and the autophagy conjugation complex.
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DOI：
10.1083/jcb.152.1.51
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发表时间：
2001-01-08
期刊：
影响因子：
--
通讯作者：
Klionsky DJ
中科院分区：
文献类型：
--
作者：
Kim J;Huang WP;Klionsky DJ
自噬是一种降解途径，通过这种途径，细胞将不必要的大量胞浆隔离成双膜小泡(自噬小体)，并将它们运送到液泡中进行回收。使用这一策略，真核细胞可以在营养饥饿的时期存活下来。在营养丰富的条件下，需要自噬机制来通过细胞质到空泡靶向(CVT)途径递送驻留的空泡水解酶-氨基肽酶I。在这两条途径中，囊泡的形成过程都需要饥饿诱导的Aut7蛋白的作用，Aut7蛋白从细胞质中招募到形成CVT囊泡和自噬小体。Aut7p的膜结合代表了囊泡形成的早期步骤。在这项研究中，我们确定了Aut7p膜结合的几个要求。在胞浆中合成后，Aut7p以一种Aut2p依赖的方式被蛋白水解性切割。虽然这一新的加工事件对于Aut7p膜结合是必不可少的，但Aut7p在重新招募到膜上之前必须与Aut1p和自噬(APG)结合复合体进行额外的物理相互作用。缺乏这些相互作用导致Aut7p的胞浆分布，而不是定位于形成CVT囊泡和自噬小体。本研究确定了APG结合系统作为Aut7p膜募集的中介的功能作用。此外，我们还证明了Aut1p是Aut7p膜募集所必需的额外因素，它与APG结合复合体和Aut7p的组分发生物理作用。这些发现定义了一系列步骤，导致Aut7p的修饰及其随后与自噬的隔离运输小泡和细胞质到空泡靶向通路的结合。
Autophagy is a degradative pathway by which cells sequester nonessential, bulk cytosol into double-membrane vesicles (autophagosomes) and deliver them to the vacuole for recycling. Using this strategy, eukaryotic cells survive periods of nutritional starvation. Under nutrient-rich conditions, autophagy machinery is required for the delivery of a resident vacuolar hydrolase, aminopeptidase I, by the cytoplasm to vacuole targeting (Cvt) pathway. In both pathways, the vesicle formation process requires the function of the starvation-induced Aut7 protein, which is recruited from the cytosol to the forming Cvt vesicles and autophagosomes. The membrane binding of Aut7p represents an early step in vesicle formation. In this study, we identify several requirements for Aut7p membrane association. After synthesis in the cytosol, Aut7p is proteolytically cleaved in an Aut2p-dependent manner. While this novel processing event is essential for Aut7p membrane binding, Aut7p must undergo additional physical interactions with Aut1p and the autophagy (Apg) conjugation complex before recruitment to the membrane. Lack of these interactions results in a cytosolic distribution of Aut7p rather than localization to forming Cvt vesicles and autophagosomes. This study assigns a functional role for the Apg conjugation system as a mediator of Aut7p membrane recruitment. Further, we demonstrate that Aut1p, which physically interacts with components of the Apg conjugation complex and Aut7p, constitutes an additional factor required for Aut7p membrane recruitment. These findings define a series of steps that results in the modification of Aut7p and its subsequent binding to the sequestering transport vesicles of the autophagy and cytoplasm to vacuole targeting pathways.
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影响因子：
7.8
作者：
Baba, M;Osumi, M;Scott, SV;Klionsky, DJ;Ohsumi, Y
通讯作者：
Ohsumi, Y
自噬体生物发生分解为不同的成核和膨胀步骤。
DOI：
10.1083/jcb.151.5.1025
发表时间：
2000-11-27
期刊：
The Journal of cell biology
影响因子：
--
作者：
Abeliovich H;Dunn WA Jr;Kim J;Klionsky DJ
通讯作者：
Klionsky DJ
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影响因子：
7.8
作者：
HARDING, TM;MORANO, KA;SCOTT, SV;KLIONSKY, DJ
通讯作者：
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影响因子：
11.4
作者：
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通讯作者：
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影响因子：
7.8
作者：
Scott, SV;Baba, M;Klionsky, DJ
通讯作者：
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