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Relationship between RNA-directed DNA polymerase (reverse transcriptase) from human acute leukemic blood cells and primate type-C viruses.

R E Gallagher·G J Todaro·R G Smith·D M Livingston·R C Gallo
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Abstract

An RNA-directed DNA polymerase was isolated from the peripheral blood leukocytes of a patient with acute myelomonocytic leukemia by successive purification of a particulate cytoplasmic fraction with endogenous, ribonuclease-sensitive DNA polymerase activity. Like RNA-directed DNA polymerase from mammalian type-C virus, the human leukemic cell enzyme efficiently utilized (A)(n).(dT)(12-18) and (C)(n).(dG)(12-18) and had an approximate molecular weight of 70,000. Further, the leukemic cell enzyme was strongly inhibited by antisera to RNA-directed DNA polymerase of primate type-C virus in a fashion similar to that noted with an extensively purified RNA-directed DNA polymerase from a person with acute myelogenous leukemia [Todaro, G.J. & Gallo, R.C. (1973), Nature 244, 206]. By these biochemical and immunological results the leukemic cell enzyme could be differentiated from all other known cellular DNA polymerases but could not be distinguished from RNA-directed DNA polymerase of primate type-C virus. We interpret these data, combined with observations published elsewhere, to indicate that human acute myelogenous leukemia cells contain components related to primate type-C virus. The parameters used in this study may provide the specificity and sensitivity required for determining the presence or absence and (if present) the relatedness of RNA-directed DNA polymerase in other cases and types of human leukemia.

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AgedAnimalsCentrifugation, Density GradientChromatography, GelCross ReactionsEpitopesGuanosine TriphosphateHaplorhiniHominidaeHumansLeukemia, Myeloid, AcuteMaleMolecular WeightRNA-Directed DNA PolymeraseRetroviridaeSpecies SpecificityTemplates, GeneticThymine NucleotidesComparative StudyJournal Article

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R E Gallagher, G J Todaro, R G Smith, D M Livingston, R C Gallo. 1974. Relationship between RNA-directed DNA polymerase (reverse transcriptase) from human acute leukemic blood cells and primate type-C viruses.. https://doi.org/10.1073/pnas.71.4.1309

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