RT Journal Article
SR Electronic
T1 Effect of Administration of 3-Methylcholanthrene on the Salt-Extractable Chromatin Proteins of Rat Liver
JF Molecular Pharmacology
JO Mol Pharmacol
FD American Society for Pharmacology and Experimental Therapeutics
SP 191
OP 198
VO 7
IS 2
A1 MABEL YEE
A1 EDWARD BRESNICK
YR 1971
UL http://molpharm.aspetjournals.org/content/7/2/191.abstract
AB It had previously been demonstrated than an increase in the efficiency of the template function of liver chromatin occurs after the administration of 3-methylcholanthrene (3-MC) to rats. The difference between control and 3-MC systems is eliminated by extraction of the chromatin with 2 M NaCl, a procedure which removes many of the nuclear proteins. The profile of 2 M NaCl-extractable protein components of liver chromatin differs after treatment of rats with 3-MC, as determined by either disc electrophoretic or gel filtration techniques. The earliest change was seen 3-6 hr after drug treatment. The kinetics of incorporations of [14C] lysine into these components is also altered after drug treatment. After a 30-min pulse with the labeled precursor, a progressive increase in the specific activity of the 2 M NaCl-extractable proteins of liver chromatin was noted up to 24 hr after 3-MC treatment. At this time, a 100% increase over control levels was observed. Under the same conditions, the incorporation of [14C] L-tryptophan into the 2 M NaCl-extractable compo nents of liver was unaffectd by drug treatment. These changes may be related to the subsequent activation of the chromatin template for RNA synthesis.