Coordinating the two protomer active sites of human topoisomerase IIalpha: nicks as topoisomerase II poisons.
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ABSTRACT:
SUBMITTER: Deweese JE
PROVIDER: S-EPMC2716134 | biostudies-literature | 2009 Feb
REPOSITORIES: biostudies-literature
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Coordinating the two protomer active sites of human topoisomerase IIalpha: nicks as topoisomerase II poisons.
Deweese Joseph E JE Osheroff Neil N
Biochemistry 20090201 7
Topoisomerase II modulates DNA topology by generating double-stranded breaks in DNA. Results of the current study indicate that the presence of a nick at one scissile bond dramatically increases the rate of cleavage by human topoisomerase IIalpha at the scissile bond on the opposite strand. We propose that this enhanced activity at the second strand coordinates the two protomer subunits of topoisomerase II and allows the enzyme to create double-stranded breaks. Finally, the presence of a nick on ...[more]
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