Effects of deoxyribonuclease I and micrococcal nuclease on the release of dexamethasone-receptor complex from nuclei of sensitive and insensitive hepatoma cell lines.
(1) Fu5 cells were sensitive to the glucocorticoid inhibition of cell growth and the hormonal induction of tyrosine aminotransferase (but not fructose-1,6-bisphosphatase and glycogen synthase). AH-130 and AH-7974 cells were insensitive to both effects. (2) The release of [3H]dexamethasone radioactivity from the nuclei of Fu5 and AH-130 cells preincubated with [3H]dexamethasone increased as the KCl concentration increased from 0 to 0.4 M, with no significant difference between the two cell lines. (3) The radioactivity was more sensitively released in Fu5 nuclei than in AH-130 nuclei upon treatment with DNAase I. The release of radioactivity was always larger than the release of DNA in both cell nuclei. In contrast to DNAase I, micrococcal nuclease treatment did not show any difference between the two cell lines in the release of radioactivity from nuclei, always showing a release of radioactivity equal to that of DNA.
D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D004273:DNA, Neoplasm / Q000096:biosynthesis; D003850:Deoxyribonuclease I; D003851:Deoxyribonucleases / Q000494:pharmacology*; D003907:Dexamethasone / Q000378:metabolism*; D004351:Drug Resistance; D004720:Endonucleases / Q000494:pharmacology*; D066298:In Vitro Techniques; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D008836:Micrococcal Nuclease / Q000494:pharmacology*; D051381:Rats; D011965:Receptors, Glucocorticoid / Q000187:drug effects* / Q000378:metabolism; D011987:Receptors, Steroid / Q000187:drug effects*; D014444:Tyrosine Transaminase / Q000096:biosynthesis
D004273:DNA, Neoplasm; D011965:Receptors, Glucocorticoid; D011987:Receptors, Steroid; D003907:Dexamethasone; D014444:Tyrosine Transaminase; D003851:Deoxyribonucleases; D004720:Endonucleases; D003850:Deoxyribonuclease I; D008836:Micrococcal Nuclease