DNA-binding mechanism and evolution of Replication Protein A

Madru, C.; Martinez-Carranza, M.; Laurent, S.; Alberti, A. C.; Chevreuil, M.; Raynal, B.; Haouz, A.; Le Meur, R. A.; Delarue, M.; Flament, D.; Kuprovic, M.; Legrand, P.; Sauguet, L.

doi:10.1101/2022.07.20.500673

bioRxiv · 10.1101/2022.07.20.500673

DNA-binding mechanism and evolution of Replication Protein A

Madru, C.·Martinez-Carranza, M.·Laurent, S.·Alberti, A. C.·Chevreuil, M.·Raynal, B.·Haouz, A.·Le Meur, R. A.·Delarue, M.·Flament, D.·Kuprovic, M.·Legrand, P.·Sauguet, L.

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Abstract

Replication Protein A (RPA) is a heterotrimeric single stranded DNA-binding protein with essential roles in DNA replication, recombination and repair, in both eukaryotic and archaeal cells. By using an integrative approach that combines three crystal structures, four cryo-EM structures in complex with single-stranded DNA (ssDNA) of different lengths, we extensively characterized RPA from Pyrococcus abyssi in different states. These structures show two essential features conserved in eukaryotes: a trimeric core and a module that promotes cooperative binding to ssDNA, as well as a newly identified archaeal-specific domain. These structures reveal for the first time how ssDNA is handed over from one RPA complex to the other, and uncover an unanticipated mechanism of self-association on ssDNA tracts. This work constitutes a significant step forward in the molecular understanding of the structure and DNA-binding mechanism of RPA, with far-reaching implications for the evolution of this primordial replication factor in Archaea and Eukarya.

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Madru, C., Martinez-Carranza, M., Laurent, S., Alberti, A. C., Chevreuil, M., Raynal, B., Haouz, A., Le Meur, R. A., Delarue, M., Flament, D., Kuprovic, M., Legrand, P., Sauguet, L.. 2022-07-21. DNA-binding mechanism and evolution of Replication Protein A. https://doi.org/10.1101/2022.07.20.500673

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