Particle-Associated RNA-Dependent DNA Polymerase and High-Molecular-Weight RNA in a Human Cell Line Derived From Polycythemia Vera Bone Marrow

Abstract

A particle fraction with a density of 1.15–1.19 g/cm³ was isolated from the cytoplasm of a human cell line established in culture from the bone marrow of an untreated patient with polycythemia vera. Electron micrographs of cross sections of cells and cell homogenates revealed virus-like particles on which DNA could be synthesized. An RNA-dependent DNA polymerase, isolated from the particles, preferred poly(rA) · oligo(dT) over poly(dA) · oligo(dT) and was able to polymerize deoxyguanosine monophosphate in a reaction stimulated by poly(rC) · oligo(dG).