Horst M, Azem A, Schatz G, Glick B S
Biozentrum, Universität Basel, Switzerland.
Biochim Biophys Acta. 1997 Jan 16;1318(1-2):71-8. doi: 10.1016/s0005-2728(96)00131-4.
Nuclear-encoded mitochondrial proteins are synthesized in the cytosol as precursors and then imported into mitochondria. Protein import into the matrix space requires the function of the mitochondrial hsp70 (mhsp70) chaperone. mhsp70 is an ATPase that acts in conjunction with two partner proteins: the Tim44 subunit of the inner membrane import complex, and the nucleotide exchange factor mGrpE. A central question concerns how mhsp70 uses the energy of ATP hydrolysis to transport precursor proteins into the matrix. Recent evidence suggests that mhsp70 is a mechanochemical enzyme that actively pulls precursors across the inner membrane.
核编码的线粒体蛋白最初以前体形式在细胞质中合成，然后被导入线粒体。将蛋白质导入线粒体基质需要线粒体热休克蛋白70（mhsp70）伴侣蛋白发挥作用。mhsp70是一种ATP酶，它与两种伴侣蛋白协同作用：内膜导入复合物的Tim44亚基和核苷酸交换因子mGrpE。一个核心问题是mhsp70如何利用ATP水解产生的能量将前体蛋白转运到基质中。最近的证据表明，mhsp70是一种机械化学酶，它能主动将前体蛋白拉过内膜。
