title: Transfection of murine multi-potent haemopoietic stem cells with an E. coli DNA alkyltransferase gene confers resistance to the toxic effects of alkylating agents.
abstract: O6-alkylguanine-DNA-alkyltransferase (ATase)-deficient murine haemopoietic stem cells were transfected, following electroporation, with a G418-selectable expression vector containing the protein coding region of the Escherichia coli ATase gene ada. Clones of cells that were resistant to G418 or the chloroethylating agent mitozolomide (Mz) were selected and most were shown to express very high levels of bacterial gene-encoded ATase. In comparison with control cells that were transfected with the parent vector, the ATase-expressing clones were considerably more resistant to the toxic effects of the methylating agents N-methyl-N-nitrosourea and methylmethanesulphonate or the chloroethylating agents Mz or taurine chloroethylnitrosourea, but unchanged in their susceptibility to the bis-chloroethylating agent nitrogen mustard. Thus alkylation damage in DNA that can be repaired by the E. coli ATase constitutes the principal lethal lesion produced by alkylating agents in murine haemopoietic stem cells and the ATase deficiency in these cells can be complemented by electroporation-mediated gene transfection.
authors.affiliation: Department of Experimental Haematology, Paterson Institute for Cancer Research, Christie Hospital, Manchester, UK.
authors.forename: J
authors.initials: J
authors.lastname: Jelinek
authors.forename: K
authors.initials: K
authors.lastname: Kleibl
authors.forename: T M
authors.initials: TM
authors.lastname: Dexter
authors.forename: G P
authors.initials: GP
authors.lastname: Margison
mesh_terms: D019883:Alkyl and Aryl Transferases; D000477:Alkylating Agents / Q000633:toxicity*; D000818:Animals; D004262:DNA Restriction Enzymes / Q000378:metabolism; D015245:Deoxyribonuclease BamHI; D015246:Deoxyribonuclease EcoRI; D004351:Drug Resistance / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005470:Fluorometry; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000201:enzymology*; D008466:Mechlorethamine / Q000633:toxicity; D008741:Methyl Methanesulfonate / Q000633:toxicity; D008770:Methylnitrosourea / Q000633:toxicity; D051379:Mice; D009588:Nitrogen Mustard Compounds / Q000633:toxicity; D009607:Nitrosourea Compounds / Q000633:toxicity; D010957:Plasmids; D013654:Taurine / Q000031:analogs & derivatives / Q000633:toxicity; D014162:Transfection; D014166:Transferases / Q000235:genetics*
chemical_list: D000477:Alkylating Agents; D009588:Nitrogen Mustard Compounds; D009607:Nitrosourea Compounds; D013654:Taurine; D008466:Mechlorethamine; C052991:1-(2-chloroethyl)-3-(2-(dimethylaminosulfonyl)ethyl)-1-nitrosourea; D008770:Methylnitrosourea; D008741:Methyl Methanesulfonate; C040369:mitozolomide; D014166:Transferases; D019883:Alkyl and Aryl Transferases; C050956:DNA alkyltransferase; D004262:DNA Restriction Enzymes; D015245:Deoxyribonuclease BamHI; D015246:Deoxyribonuclease EcoRI