INITIATION FACTOR ACTIVITY IN LIVER AFTER 3-METHYLCHOLANTHRENE ADMINISTRATION

¹ Department of Cell and Molecular Biology, Medical College of Georgia

A liver polyribosomal extract was prepared by high-salt treatment from 3-MC- or BNF-treated rats and was compared with a similarly prepared extract from control liver with respect to the ability to stimulate poly U-directed ¹⁴C-phenylalanine incorporation in a cell-free system from liver. The results demonstrated a several-fold stimulation by both extracts from 3-MC- and BNF-treated animals. It was shown that neither amino acid activation nor elongation was affected by such treatment. The ribosomal high-salt extract was separated into M₁ and M₃ + M₂ fractions. The stimulatory effect was associated with the latter. Implications of a possible role of these high-salt factors in enzyme induction are discussed.