Download MendeleyStructural insights into the gating of DNA passage by the topoisomerase II DNA-gate.
Chen, S.F., Huang, N.L., Lin, J.H., Wu, C.C., Wang, Y.R., Yu, Y.J., Gilson, M.K., Chan, N.L.(2018) Nat Commun 9: 3085-3085
- PubMed: 30082834
- DOI: https://doi.org/10.1038/s41467-018-05406-y
- Primary Citation of Related Structures:
5ZEN, 5ZQF, 5ZRF - PubMed Abstract:
Type IIA topoisomerases (Top2s) manipulate the handedness of DNA crossovers by introducing a transient and protein-linked double-strand break in one DNA duplex, termed the DNA-gate, whose opening allows another DNA segment to be transported through to change the DNA topology. Despite the central importance of this gate-opening event to Top2 function, the DNA-gate in all reported structures of Top2-DNA complexes is in the closed state. Here we present the crystal structure of a human Top2 DNA-gate in an open conformation, which not only reveals structural characteristics of its DNA-conducting path, but also uncovers unexpected yet functionally significant conformational changes associated with gate-opening. This structure further implicates Top2's preference for a left-handed DNA braid and allows the construction of a model representing the initial entry of another DNA duplex into the DNA-gate. Steered molecular dynamics calculations suggests the Top2-catalyzed DNA passage may be achieved by a rocker-switch-type movement of the DNA-gate.
Organizational Affiliation:
Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan.
