RecA-dependent incision of psoralen-crosslinked DNA by (A)BC excinuclease.
Previous work to elucidate the mechanism of crosslink repair by (A)BC excinuclease has shown that a psoralen-crosslinked duplex is selectively incised in the furan-side strand, while a three-stranded structure is incised in the pyrone-side strand of the crosslink. These observations support a sequential incision and recombination model for the complete error-free repair of a psoralen crosslink. The work presented here extends these findings by demonstrating that in the presence of RecA protein and a homologous DNA oligonucleotide, (A)BC excinuclease is induced to incise the pyrone-side strand of a crosslinked double-stranded plasmid molecule. This finding adds further support to the current model for error-free crosslink repair.
Cheng
S
S
Department of Chemistry, University of California, Berkeley 94720.
Sancar
A
A
Hearst
J E
JE
D001483:Base Sequence; D003001:Cloning, Molecular; D003090:Coliphages; D003432:Cross-Linking Reagents; D004260:DNA Repair; D004279:DNA, Viral / Q000235:genetics; D004706:Endodeoxyribonucleases / Q000378:metabolism*; D029968:Escherichia coli Proteins; D011564:Furocoumarins; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D011938:Rec A Recombinases / Q000378:metabolism*
D003432:Cross-Linking Reagents; D004279:DNA, Viral; D029968:Escherichia coli Proteins; D011564:Furocoumarins; D011938:Rec A Recombinases; D004706:Endodeoxyribonucleases; C036385:endodeoxyribonuclease uvrABC