INTERACTION OF HSP70 WITH UNFOLDED PROTEINS - EFFECTS OF TEMPERATURE AND NUCLEOTIDES ON THE KINETICS OF BINDING
INTERACTION OF HSP70 WITH UNFOLDED PROTEINS - EFFECTS OF TEMPERATURE AND NUCLEOTIDES ON THE KINETICS OF BINDING
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DOI：
10.1073/pnas.88.13.5719
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发表时间：
1991-07-01
影响因子：
11.1
通讯作者：
FINK, AL
中科院分区：
文献类型：
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作者：
PALLEROS, DR;WELCH, WJ;FINK, AL
圆二色性和HPLC凝胶过滤被用来显示，胞质热休克蛋白70是热稳定的，但经历了构象转变（中点，43 ° C; 57 ° C，在ATP或ADP的存在下），导致寡聚化。HSP 70以温度依赖性方式结合未折叠的蛋白质，但不结合折叠的蛋白质;复合物形成仅在生理相关温度下才有意义。hsp 70比ATP更紧密地结合ADP以形成二元复合物，其比游离hsp 70更快速地结合未折叠蛋白。ADP还抑制ATP诱导的hsp 70-蛋白复合物的解离。提出了热休克蛋白70-核苷酸二元复合物的调节作用。
Circular dichroism and HPLC gel filtration were used to show that cytosolic hsp70 is thermally stable but undergoes a conformational transition (midpoint, 43-degrees-C; 57-degrees-C in the presence of ATP or ADP) leading to oligomerization. hsp70 binds to unfolded, but not to folded, proteins in a temperature-dependent manner; complex formation is significant only at physiologically relevant temperatures. hsp70 binds ADP more tightly than ATP to form a binary complex, which binds to the unfolded protein more rapidly than free hsp70. ADP also inhibits the ATP-induced dissociation of the hsp70-protein complex. A regulatory role for the hsp70-nucleotide binary complexes is proposed.