Distribution of Mason-Pfizer Virus-Specific Sequences in the DNA of Primates

Abstract

Iodinated Mason-Pfizer virus (MPV) 60-70S RNA was used in molecular hybridization experiments to determine the distribution of MPV-specific proviral sequences in the DNA of primates. About 20% of the MPV genome is present as endogenous provirus in rhesus monkeys. Competitive hybridization experiments showed no homology between MPV 60-70S RNA and the 60-70S RNA of M7, RD-114 and the simian sarcoma virus. No MPV-specific proviral sequences were detected in the DNA of apparently normal tissues of various species of New World monkeys, apes and humans. The part of the MPV genome that is endogenous to rhesus is also endogenous to the other species of Old World monkeys examined: baboon, African green and patas. COt1/2 [half-renaturation time, where Co = initial DNA concentration and t = time of hybridization] values and final extent of hybridization were the same for all 4 spp. Tm [melting temperature] values of MPV 60-70S RNA and DNA of all 4 spp. were identical. The removal of MPV sequences endogenous to rhesus tissues by recycling against rhesus DNA resulted in the loss of any hybridizable MPV RNA to the DNA of baboon, African green and patas tissues. Mixing experiments of rhesus, African green and baboon DNA resulted in the same kinetics of hybridization as did rhesus DNA alone, when hybridized with MPV 60-70S RNA. Sequences that constitute an integral part of the MPV genome are apparently conserved in the DNA of several different species of Old World monkeys.