Influence of polyamines on DNA binding of heat shock and activator protein 1 transcription factors induced by heat shock.
Polyamine depletion, obtained in FAO cells with specific inhibitors of biosynthetic enzymes, prevents or decreases the accumulation of hsp 70 mRNA following heat shock [Desiderio et al., Hepatology 24 (1996) 150-156]. The present study shows that under conditions of spermidine depletion caused by alpha-difluoromethylornithine, the DNA binding capacity of the transcription factor HSF induced by heat shock undergoes a severe and prompt deactivation. Replenishment of the spermidine pool before heat shock re-establishes the DNA binding activity of HSF and the inducibility of hsp 70 mRNA. Similar to HSF, but with a different time-course, the DNA binding of the transcription factor AP-1 activated by heat shock is also impaired in spermidine-depleted cells and reversed by exogenous spermidine. STAT3 provides an example of a transcription factor slightly activated by heat shock but insensitive to polyamine decrease.
Desiderio
M A
MA
Istituto di Patologia Generale dell'Università degli Studi di Milano, Centro di Studio sulla Patologia Cellulare del CNR, Milan, Italy.
Dansi
P
P
Tacchini
L
L
Bernelli-Zazzera
A
A
D000818:Animals; D001483:Base Sequence; D015317:Biogenic Polyamines / Q000502:physiology*; D004247:DNA / Q000378:metabolism*; D017931:DNA Primers; D000518:Eflornithine / Q000494:pharmacology; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006207:Half-Life; D018869:Heat-Shock Response; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D013095:Spermidine / Q000494:pharmacology; D018808:Transcription Factor AP-1 / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D015317:Biogenic Polyamines; D017931:DNA Primers; D018840:HSP70 Heat-Shock Proteins; D012333:RNA, Messenger; D018808:Transcription Factor AP-1; D004247:DNA; D013095:Spermidine; D000518:Eflornithine