Choline phosphotransferase and phosphatidyl ethanolamine methyltransferase activities in spleen microsomes of mice infected with Friend virus.

SummaryCholine phosphotransferase and phosphatidyl ethanolamine methyltrans-ferase enzymatic activities (nmoles phosphatidyl choline/min/mg protein) have been determined in spleen microsomes of Friend virus infected BALB/c male mice at 5, 10, 14 and 21 days following inoculation of the virus. There is marked stimulation of the choline phosphotransferase activity in the virus infected spleens. There is less stimulation of the phosphatidyl ethanola-mine methyltransferase.The incorporation of 1,2-14C-choline and 1,2-14C-ethanolamine into the total phos-pholipid-P, total lecithin-P, and the phosphatidyl choline-P fractions of spleen microsomes at 1, 2 and 3 hrs after intraperi-toneal injection of the isotopic compounds in 14 day old viral infected mice was studied. There was a greater incorporation of 1,2-14C-choline into the total phospho-lipid-P, total lecithin-P and phosphatidyl choline fractions in the microsomes of the viral infected spleens than in control mice. Friend virus greatly stimulates the choli...