Involvement of 70-kD heat-shock proteins in peroxisomal import.
Involvement of 70-kD heat-shock proteins in peroxisomal import.
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DOI：
10.1083/jcb.125.5.1037
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发表时间：
1994-06
期刊：
影响因子：
--
通讯作者：
Welch WJ
中科院分区：
文献类型：
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作者：
Walton PA;Wendland M;Subramani S;Rachubinski RA;Welch WJ
本报告描述了70-kD热休克蛋白(HSP70)参与了蛋白质进入哺乳动物过氧化物体的过程。采用基于微量注射的分析(Walton，P.A.，S.J.Gould，J.R.Feramisco和S.Subramani)。1992年。摩尔。细胞生物。12：531-541)，我们证明了HSP70家族的蛋白质与输入到过氧化体基质中的蛋白质相关。通过联合注射针对构成HSP70蛋白的抗体(Hsp73)，可以抑制过氧化体蛋白的进口。在渗透性细胞分析中(Wendland和Subramani。1993年。J.细胞生物学。120：675-685)，针对HSP70蛋白的抗体被证明能抑制过氧化体蛋白的输入。外源HSP70蛋白可以克服抑制作用。纯化的大鼠肝脏过氧化物体具有相关的HSP70蛋白。在过氧化体增殖的条件下，相关的HSP70的数量增加。此外，酶保护实验表明，HSP70分子位于过氧化体外膜上。最后，热休克细胞的过程导致了过氧化体蛋白进口的相当大的延迟。综上所述，这些结果表明细胞质HSP70家族的热休克蛋白参与了过氧化体蛋白的输入。
This report describes the involvement of 70-kD heat-shock proteins (hsp70) in the import of proteins into mammalian peroxisomes. Employing a microinjection-based assay (Walton, P. A., S. J. Gould, J. R. Feramisco, and S. Subramani. 1992. Mol. Cell Biol. 12:531-541), we demonstrate that proteins of the hsp70 family were associated with proteins being imported into the peroxisomal matrix. Import of peroxisomal proteins could be inhibited by coinjection of antibodies directed against the constitutive hsp70 proteins (hsp73). In a permeabilized-cell assay (Wendland and Subramani. 1993. J. Cell Biol. 120:675-685), antibodies directed against hsp70 proteins were shown to inhibit peroxisomal protein import. Inhibition could be overcome by the addition of exogenous hsp70 proteins. Purified rat liver peroxisomes were shown to have associated hsp70 proteins. The amount of associated hsp70 was increased under conditions of peroxisomal proliferation. Furthermore, proteinase protection assays indicated that the hsp70 molecules were located on the outside of the peroxisomal membrane. Finally, the process of heat-shocking cells resulted in a considerable delay in the import of peroxisomal proteins. Taken together, these results indicate that heat-shock proteins of the cytoplasmic hsp70 family are involved in the import of peroxisomal proteins.