title: Characterization of RNase H activity associated with reverse transcriptase in simian foamy virus type 1.
abstract: Spumavirinae or foamy viruses have been shown to have a characteristic RNA-dependent DNA polymerase activity. We demonstrate here the existence of an RNase H activity that copurifies with the 81-kilodalton monomeric polypeptide, which carries the RNA-dependent DNA polymerase activity of simian foamy virus type 1. RNase H degrades RNA hybrid substrates; however, it does not solubilize single-stranded RNAs. Inactivation assays with heat, high levels of bivalent cations, ethidium bromide, and sodium fluoride suggest that the RNase H catalytic site could be topologically independent from the DNA polymerase catalytic site.
mesh_terms: D000818:Animals; D002413:Cations, Divalent; D002460:Cell Line; D002846:Chromatography, Affinity; D004285:Dogs; D004722:Endoribonucleases / Q000302:isolation & purification* / Q000378:metabolism; D004789:Enzyme Activation; D006358:Hot Temperature; D012194:RNA-Directed DNA Polymerase / Q000302:isolation & purification*; D012190:Retroviridae / Q000201:enzymology*; D016914:Ribonuclease H; D016092:Spumavirus / Q000201:enzymology*
chemical_list: D002413:Cations, Divalent; D012194:RNA-Directed DNA Polymerase; D004722:Endoribonucleases; D016914:Ribonuclease H