Heat shock factor-1 and the heat shock cognate 70 protein associate in high molecular weight complexes in the cytoplasm of NIH-3T3 cells.
Interaction of heat shock transcription factor-1 (HSF-1) with the seventy kilodalton heat shock cognate protein (HSC70) was examined in NIH 3T3 cells. HSF-1 was found in the cytoplasm of non-stressed cells associated with HSC70 in large (Mr 400-500,000) complexes. After heat shock, HSF-1 became concentrated in the nucleus in smaller, more stable complexes that did not contain HSC70, an indication of significant rearrangement within the complexes. These experiments show a profound effect of heat shock on the structure and stability of HSF-1 complexes during nuclear localization and support the hypothesis that HSC70 binding may control HSF-1 function.
Nunes
S L
SL
Dana Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.
Calderwood
S K
SK
D016475:3T3 Cells; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000302:isolation & purification / Q000378:metabolism*; D000076249:Heat Shock Transcription Factors; D006358:Hot Temperature; D006801:Humans; D051379:Mice; D008970:Molecular Weight; D011485:Protein Binding; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D014157:Transcription Factors / Q000302:isolation & purification / Q000378:metabolism
D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D018840:HSP70 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; D011994:Recombinant Proteins; D014157:Transcription Factors