Mooney B, Harmey M A
University College Dublin, Belfield, Ireland.
Biochem Biophys Res Commun. 1996 Jan 5;218(1):309-13. doi: 10.1006/bbrc.1996.0054.
Hsp70 was localized to the mitochondrial outer membranes of bean and cauliflower mitochondria. Western blotting showed that the outer membrane hsp70 was antigenically distinct from the mitochondrial-matrix hsp70, but was similar to the cytosolic form. The protein was resistant to solubilization with 200 mM sodium carbonate which showed the hsp70 was tightly bound to the outer membrane. Proteinase K studies suggested that the hsp70 was partially exposed to the cytosol with approximately 17% of the protein protease-accessible. It is suggested that the position of the outer membrane hsp70 could relate to a precursor unfolding function during protein import into mitochondria.
热休克蛋白70（Hsp70）定位于菜豆和花椰菜线粒体的线粒体外膜。蛋白质免疫印迹分析表明，外膜热休克蛋白70在抗原性上与线粒体基质热休克蛋白70不同，但与胞质形式相似。该蛋白对200 mM碳酸钠的溶解具有抗性，这表明热休克蛋白70与外膜紧密结合。蛋白酶K研究表明，热休克蛋白70部分暴露于胞质溶胶中，约17%的蛋白质可被蛋白酶作用。有人认为，外膜热休克蛋白70的位置可能与蛋白质导入线粒体过程中的前体解折叠功能有关。
