Abstract
Wealing rats were injected intraperitoneally with C14-AICA and after 1, 4, 8 and 24 hours, the livers were removed. Nuclear and cytoplasmic ribonucleoproteins were fractionated by DEAE cellulose column chromatography. Cytoplasmic ribonucleoprotein can be divided into four fractions: The supernatant fraction was of nuclear origin and the most metabolically active; the post-microsomal fraction was found radioactive and its specific activity became higher than that of the supernatant fraction, over a period of 4 hours; radioactivities appeared in S-RNA and ribosomes in the later stage.
DNA was not wholly incorporated by C14-AICA. DNA, activite in metabolism, was isolated by means of ECTEOLA cellulose column chromatography. Simultaneous administration of purine and pyrimidine precursors resulted in higher incorporation of labeled precursors into the supernatant fraction.
This investigation was supported by grants from the National Institute of Health, U. S. A. (CY-5869 CY).
