For technical details, see Materials and Methods To detect elution profile, UV-280 absorbance (A280, blue line) and DNApolβ specific catalytic activity (E, red line) were monitored. 1A: Agarose gel DNA electrophoresis: 1, 3 – single strand DNA fragments (markers); 2 –DNA sequences pool processed in vitro by the β-like DNA polymerase purified from the HL60 cell chromatin. 1B, 1C: Isoelectric focusing of the β-like DNA polymerase purified from the HL60 cell chromatin performed along with the commercial markers sets. 1D: SDS–PAGE analysis of the purified HL60 chromatin associated β–like polymerse. 1 – Markers set; 2 – 5, 5.0, 1.0, 0.5, μg pure enzyme per a slab gel. 1E: Isoelectric focusing of the cell nuclei subfraction proteins: 1, acidic glycoprotein of the HeLa cell plasmatic membrane (Courtesy, RAMS Institute for Carcinogenesis Research, Moscow, Russia); 2, HeLa cell histone H1A (Courtesy, RAMS Institute for Carcinogenesis Research, Moscow, Russia); 3, β–like DNA polymerase purified from chromatin of HL60 cells; 4 –10, cell nuclei subfractions total protein; 4, 6, 7, chromatin from the healthy donor myelocytes, three individuals; 5, HL60 cell nuclei total protein; 8, 9, HL60 chromatin proteins; 10, HL60 nucleoplasm proteins.

Figure 1: Fractionation of HL60 cell chromatin proteins on toyopearl HW55F column and a subsequent evaluation of physico–chemical properties and catalytic function of the resulted–purified β -like DNA polymerase.