Protein import into mitochondria: ATP-dependent protein translocation activity in a submitochondrial fraction enriched in membrane contact sites and specific proteins.
Protein import into mitochondria: ATP-dependent protein translocation activity in a submitochondrial fraction enriched in membrane contact sites and specific proteins.
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DOI：
10.1083/jcb.109.6.2603
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发表时间：
1989-12
期刊：
影响因子：
--
通讯作者：
Schatz G
中科院分区：
文献类型：
--
作者：
Pon L;Moll T;Vestweber D;Marshallsay B;Schatz G
为了确定酵母线粒体从细胞质中输入蛋白质的膜区域，我们用两种不同的部分易位前体蛋白标记了这些区域。其中之一是结合到线粒体表面的ATP耗尽的线粒体，并随后被追赶到线粒体后，加入ATP。另一个中间体在蛋白质输入位点不可逆地穿过两个线粒体膜。在线粒体的亚馏分，这两个中间体cofractionated与膜囊泡的浮力密度之间的内膜和外膜。当这些囊泡从含有可追踪中间体的线粒体制备时，它们在加入ATP后将其内化。一个不可水解的ATP类似物是无活性的。该囊泡部分含有封闭的，右侧外的内膜囊泡连接到泄漏的外膜囊泡。囊泡含有细胞质核糖体的线粒体结合位点，并含有相对于内膜或外膜标记物富集的几种线粒体蛋白。通过免疫电子显微镜，这些蛋白质中的两个集中在线粒体内膜和外膜紧密并列的位点。我们的结论是，这些囊泡包含两个线粒体膜之间的接触点，这些网站是进入线粒体的蛋白质的入口点，并且分离的囊泡仍然易位能力。
To identify the membrane regions through which yeast mitochondria import proteins from the cytoplasm, we have tagged these regions with two different partly translocated precursor proteins. One of these was bound to the mitochondrial surface of ATP-depleted mitochondria and could subsequently be chased into mitochondria upon addition of ATP. The other intermediate was irreversibly stuck across both mitochondrial membranes at protein import sites. Upon subfraction of the mitochondria, both intermediates cofractionated with membrane vesicles whose buoyant density was between that of inner and outer membranes. When these vesicles were prepared from mitochondria containing the chaseable intermediate, they internalized it upon addition of ATP. A non-hydrolyzable ATP analogue was inactive. This vesicle fraction contained closed, right-side-out inner membrane vesicles attached to leaky outer membrane vesicles. The vesicles contained the mitochondrial binding sites for cytoplasmic ribosomes and contained several mitochondrial proteins that were enriched relative to markers of inner or outer membranes. By immunoelectron microscopy, two of these proteins were concentrated at sites where mitochondrial inner and outer membranes are closely apposed. We conclude that these vesicles contain contact sites between the two mitochondrial membranes, that these sites are the entry point for proteins into mitochondria, and that the isolated vesicles are still translocation competent.
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影响因子：
64.5
作者：
SCHLEYER, M;NEUPERT, W
通讯作者：
NEUPERT, W
DOI：
10.1083/jcb.65.1.1
发表时间：
1975-04
期刊：
The Journal of cell biology
影响因子：
--
作者：
Kellems RE;Allison VF;Butow RA
通讯作者：
Butow RA
影响因子：
11.4
作者：
HURT, EC;PESOLDHURT, B;SCHATZ, G
通讯作者：
SCHATZ, G
DOI：
10.1073/pnas.81.15.4819
发表时间：
1984-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
YAFFE, MP;SCHATZ, G
通讯作者：
SCHATZ, G
影响因子：
64.8
作者：
EILERS, M;SCHATZ, G
通讯作者：
SCHATZ, G