title: Recognition and repair of the CC-1065-(N3-adenine)-DNA adduct by the UVRABC nucleases.
abstract: The recognition and repair of the helix-stabilizing and relatively nondistortive CC-1065-(N3-adenine)-DNA adduct by UVRABC nuclease has been investigated both in vivo with phi X174 RFI DNA by a transfection assay and in vitro by a site-directed adduct in a 117 base pair fragment from M13mp1. CC-1065 is a potent antitumor antibiotic produced by Streptomyces zelensis which binds within the minor groove of DNA through N3 of adenine. In contrast to the helix-destabilizing and distortive modifications of DNA caused by ultraviolet light or N-acetoxy-2-(acetylamino)fluorene, CC-1065 increases the melting point of DNA and decreases the S1 nuclease activity. Using a viral DNA-Escherichia coli transfection system, we have found that the uvrA, uvrB, and uvrC genes, which code for the major excision repair proteins for UV- and NAAAF-induced DNA damage, are also involved in the repair of CC-1065-DNA adducts. In contrast, the uvrD gene product, which has been found to be involved in the repair of UV damage, has no effect in repairing CC-1065-DNA adducts. Purified UVRA, UVRB, and UVRC proteins must work in concert to incise the drug-modified phi X174 RFI DNA. Using a site-directed and multiple CC-1065 modified (MspI-BstNI) 117 base pair fragment from M13mp1, we have found that UVRABC nuclease incises at the eighth phosphodiester bond on the 5' side of the CC-1065-DNA adduct on the drug-modified strand.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: University of Texas System Cancer Center, Science Park-Research Division, Smithville 78957.
authors.forename: M S
authors.initials: MS
authors.lastname: Tang
authors.forename: C S
authors.initials: CS
authors.lastname: Lee
authors.forename: R
authors.initials: R
authors.lastname: Doisy
authors.forename: L
authors.initials: L
authors.lastname: Ross
authors.forename: D R
authors.initials: DR
authors.lastname: Needham-VanDevanter
authors.forename: L H
authors.initials: LH
authors.lastname: Hurley
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000378:metabolism; D000903:Antibiotics, Antineoplastic / Q000378:metabolism*; D010584:Bacteriophage phi X 174; D001483:Base Sequence; D004247:DNA / Q000378:metabolism*; D018736:DNA Adducts; D004260:DNA Repair; D004279:DNA, Viral / Q000378:metabolism*; D000080890:Duocarmycins; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D007211:Indoles; D007933:Leucomycins / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D013379:Substrate Specificity; D014162:Transfection
chemical_list: D000903:Antibiotics, Antineoplastic; C055641:CC-1065-(N(3)-adenine)-DNA; D018736:DNA Adducts; D004279:DNA, Viral; D000080890:Duocarmycins; D029968:Escherichia coli Proteins; D007211:Indoles; D007933:Leucomycins; C018782:CC 1065; D004247:DNA; D004706:Endodeoxyribonucleases; C036385:endodeoxyribonuclease uvrABC; D000225:Adenine