title: Deoxyribonuclease I sensitivity of plasmid genomes in teratocarcinoma-derived stem and differentiated cells.
abstract: The DNase I (EC 3.1.21.1) sensitivities of the simian virus 40 (SV40) genome, the pBR322 genome, and the herpes simplex virus type 1 thymidine kinase (HSV-1 tk) gene have been compared in teratocarcinoma-derived stem (12-1) and differentiated (12-1a) cell lines established by transfection of thymidine kinase (ATP:thymidine 5'-phosphotransferase, EC 2.7.1.21)-deficient F9 cells with DNA from a tripartite plasmid genome consisting of the pBR322 genome, the SV40 genome, and the HSV-1 tk gene. HSV-1 tk is present in both stem and differentiated cells; SV40 early proteins are present in differentiated cells but not in stem cells; the pBR322 genome is not expressed in either cell type. The SV40 and pBR322 genomes are more sensitive to DNase I digestion in stem cells than in differentiated cells, reflecting the DNase I-hypersensitivity of total stem-cell chromatin. The HSV-1 tk gene is the least sensitive to DNase I digestion in both cell types.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D002843:Chromatin / Q000648:ultrastructure*; D004269:DNA, Bacterial / Q000378:metabolism; D003851:Deoxyribonucleases / Q000378:metabolism*; D005786:Gene Expression Regulation; D005814:Genes, Viral; D051379:Mice; D010957:Plasmids; D013539:Simian virus 40 / Q000235:genetics; D018139:Simplexvirus / Q000201:enzymology; D013724:Teratoma / Q000503:physiopathology*; D013937:Thymidine Kinase / Q000235:genetics
chemical_list: D002843:Chromatin; D004269:DNA, Bacterial; D013937:Thymidine Kinase; D003851:Deoxyribonucleases