Cryo-EM structure of Pol κ-DNA-PCNA holoenzyme and implications for polymerase switching in DNA lesion bypass
Type
PreprintAuthors
Lancey, Claudia
Tehseen, Muhammad

Takahashi, Masateru

Sobhy, Mohamed Abdelmaboud
Ragan, Timothy J.

Crehuet, Ramon

Hamdan, Samir

De Biasio, Alfredo

KAUST Department
Biological and Environmental Sciences and Engineering (BESE) DivisionBioscience Program
Laboratory of DNA Replication and Recombination
Date
2020-07-11Permanent link to this record
http://hdl.handle.net/10754/664430
Metadata
Show full item recordAbstract
Replacement of the stalled replicative polymerase (Pol δ) at a DNA lesion by the error-prone DNA polymerase κ (Pol κ) restarts synthesis past the lesion to prevent genome instability. The switching from Pol δ to Pol κ is mediated by the processivity clamp PCNA but the structural basis of this mechanism is unknown. We determined the Cryo-EM structures of human Pol κ-DNA-PCNA complex and of a stalled Pol δ-DNA-PCNA complex at 3.9 and 4.7 Å resolution, respectively. In Pol κ complex, the C-terminus of the PAD domain docks the catalytic core to one PCNA protomer in an angled orientation, bending the DNA exiting Pol κ active site through PCNA. In Pol δ complex, the DNA is disengaged from the active site but is retained by the thumb domain. We present a model for polymerase switching facilitated by Pol κ recruitment to PCNA and Pol κ conformational sampling to seize the DNA from stalled Pol δ assisted by PCNA tilting.Citation
Lancey, C., Tehseen, M., Takahashi, M., Sobhy, M. A., Ragan, T. J., Crehuet, R., … De Biasio, A. (2020). Cryo-EM structure of Pol κ-DNA-PCNA holoenzyme and implications for polymerase switching in DNA lesion bypass. doi:10.1101/2020.07.10.196956Sponsors
This research was supported by King Abdullah University of Science and Technology through core funding (to S.M.H.), and by the Wellcome Trust (to A.D.B.). R.C. acknowledges funding from the MINECO (CTQ2016-78636-P) and to AGAUR, (2017 SGR 324). The MD project has been carried out using CSUC resources. We acknowledge The Midlands Regional Cryo-EM Facility at the Leicester Institute of Structural and Chemical Biology (LISCB), major funding from MRC (MC_PC_17136). We thank Christos Savva (LISCB, University of Leicester) for his help in Cryo-EM data collection and advice on data processing.Publisher
Cold Spring Harbor LaboratoryAdditional Links
http://biorxiv.org/lookup/doi/10.1101/2020.07.10.196956https://www.biorxiv.org/content/biorxiv/early/2020/07/10/2020.07.10.196956.full.pdf
ae974a485f413a2113503eed53cd6c53
10.1101/2020.07.10.196956