Interaction of hsp70 with unfolded proteins: effects of temperature and nucleotides on the kinetics of binding.
AUTOR(ES)
Palleros, D R
RESUMO
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.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=51949Documentos Relacionados
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