Does cruciform DNA provide a recognition signal for DNA-topoisomerase II?
Topoisomerase II displays higher affinity for supercoiled DNA compared to the same relaxed DNA. Moreover, cruciform structures are formed in topologically constrained DNA. Here we report that, using S1 nuclease experiments on supercoiled DNA, hairpin structures are located close to numerous topoisomerase II cleavage sites on the BPV I genome. Therefore, DNA secondary structure may play a role in the recognition mechanism of DNA by topoisomerase II.
Pognan
F
F
Laboratoire de Biochimie-Enzymologie, URA 147, Institut Gustave-Roussy, Villejuif, France.
Paoletti
C
C
D001483:Base Sequence; D015139:Blotting, Southern; D052688:Bovine papillomavirus 1 / Q000235:genetics; D002384:Catalysis; D004250:DNA Topoisomerases, Type II / Q000378:metabolism*; D004278:DNA, Superhelical / Q000737:chemistry / Q000378:metabolism*; D004279:DNA, Viral / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D015719:Single-Strand Specific DNA and RNA Endonucleases
D004278:DNA, Superhelical; D004279:DNA, Viral; D015719:Single-Strand Specific DNA and RNA Endonucleases; D004250:DNA Topoisomerases, Type II