[Glucocorticoid-receptor complexes of rat liver. I. Kinetic and equilibrium parameters of their interaction with DNA: ionic strength and temperature dependence].
The interaction of about 2000-fold purified rat liver glucocorticoid-receptor complexes (RGC) with DNA immobilized on cellulose was investigated. The sedimentation coefficient of GRC before or after purification is about 4S in 0.3 M NaCl. The parameters of GRC-DNA interaction were quantitatively determined using arbitrary constants expressed in M of DNA nucleotide residues. The GRC oligomeric forms which are predominant in low ionic strength media are supposed to have a higher DNA-binding affinity as compared to the monomeric forms which are predominant in high salt solutions. The interaction of GRC with DNA-cellulose qualitatively differs from the interaction of GRC with phosphocellulose. This suggests that electrostatic forces do not determine the formation of GRC-DNA complexes. So, in addition to nonspecific interaction, some specific "recognition" in GRC-DNA complexes may occur. Calculations made on the basis of GRC-DNA binding parameters derived for the conditions close to physiological (0.15 M NaCl, 20-30 degrees C, pH 7.4) demonstrate that rapid and nearly complete in vivo translocation of GRC form cytoplasm to nuclei may be a consequence of direct interaction of GRC with cellular DNA.
D000818:Animals; D004247:DNA / Q000378:metabolism*; D005938:Glucocorticoids / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D046911:Macromolecular Substances; D008297:Male; D009994:Osmolar Concentration; D011485:Protein Binding; D011487:Protein Conformation; D051381:Rats; D011965:Receptors, Glucocorticoid / Q000302:isolation & purification / Q000378:metabolism*; D011987:Receptors, Steroid / Q000378:metabolism*; D013696:Temperature
D005938:Glucocorticoids; D046911:Macromolecular Substances; D011965:Receptors, Glucocorticoid; D011987:Receptors, Steroid; D004247:DNA
Gliukokortikoid-retseptornye kompleksy pecheni krys. I. Kineticheskie i ravnovesnye parametry vzaimodeĭstviia s DNK: vliianie ionnoĭ sily i temperatury.