Phosphoribosylamidotransferase: regulation of activity in virus-induced murine leukemia by purine nucleotides.

Infection with Friend leukemia virus causes a marked increase in the activity of splenic phosphoribosylamidotransferase in mice. Intraperitoneal injection of purine nucleotides and their free bases inhibits this enzyme. This is the first example of the control of phosphoribosylamidostransferase in vivo in the mammalian system as well as in virus-induced leukemia. Experiments in vitro support the findings in vivo.