INTERACTION OF HSP-70 WITH NEWLY SYNTHESIZED PROTEINS - IMPLICATIONS FOR PROTEIN FOLDING AND ASSEMBLY
INTERACTION OF HSP-70 WITH NEWLY SYNTHESIZED PROTEINS - IMPLICATIONS FOR PROTEIN FOLDING AND ASSEMBLY
复制标题
DOI：
10.1126/science.2188360
复制
发表时间：
1990-05-18
期刊：
影响因子：
56.9
通讯作者：
WELCH, WJ
中科院分区：
文献类型：
--
作者：
BECKMANN, RP;MIZZEN, LA;WELCH, WJ
热休克蛋白70（Hsp 70）家族参与翻译后蛋白质的组装和转位。研究了正常细胞中胞浆形式的Hsp 70（Hsp 72，73）与新生蛋白的结合，发现其是瞬时的和三磷酸腺苷（ATP）依赖的。热休克蛋白72，73与新合成的蛋白质的相互作用似乎发生协同作用，因为新生的多肽释放过早的多聚体在体内可以被分离在一个复杂的热休克蛋白72，73。此外，从短期[35 S] Met标记的细胞（脉冲）分离的多核糖体显示，热休克蛋白72，73与新生的多肽链。在经历压力的细胞中，新合成的蛋白质与热休克蛋白72，73共免疫沉淀;然而，与正常细胞相反，与热休克蛋白72，73的相互作用不是短暂的。与这些数据一致的模型表明，在正常生长条件下，胞质热休克蛋白72，73与新生多肽的相互作用短暂，以促进正确的折叠，代谢应激干扰这些事件。
The 70-kilodalton family of heat shock proteins (Hsp 70) has been implicated in posttranslational protein assembly and translocation. Binding of cytosolic forms of Hsp 70 (Hsp 72, 73) with nascent proteins in the normal cells was investigated and found to be transient and adenosine triphosphate (ATP)-dependent. Interaction of Hsp 72, 73 with newly synthesized proteins appeared to occur cotranslationally, because nascent polypetides released prematurely from polysomes in vivo can be isolated in a complex with Hsp 72, 73. Moreover, isolation of polysomes from short-term [35S]Met-labeled cells (pulsed) revealed that Hsp 72, 73 associated with nascent polypeptide chains. In cells experiencing stress, newly synthesized proteins co-immunoprecipitated with Hsp 72, 73; however, in contrast to normal cells, interaction with Hsp 72, 73 was not transient. A model consistent with these data suggests that under normal growth conditions, cystosolic Hsp 72,73 interaction transiently with nascent polypeptides to facilitate proper folding, and that metabolic stress interferes with these events.