Communication between DNA polymerases and Replication Protein A within the archaeal replisome

Martinez-Carranza, M.; Vialle, L.; Madru, C.; Cordier, F.; Dizkirici Tekpinar, A.; Haouz, A.; Legrand, P.; Le Meur, R. A.; England, P.; Dulermo, R.; Guijarro, I. J.; Henneke, G.; Sauguet, L.

doi:10.1101/2024.04.29.591592

bioRxiv · 10.1101/2024.04.29.591592

Communication between DNA polymerases and Replication Protein A within the archaeal replisome

Martinez-Carranza, M.·Vialle, L.·Madru, C.·Cordier, F.·Dizkirici Tekpinar, A.·Haouz, A.·Legrand, P.·Le Meur, R. A.·England, P.·Dulermo, R.·Guijarro, I. J.·Henneke, G.·Sauguet, L.

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Abstract

Replication Protein A (RPA) plays a pivotal role in DNA replication by coating and protecting exposed single-stranded DNA, and acting as a molecular hub that recruits additional replication factors. We demonstrated that archaeal RPA hosts a winged-helix domain (WH) that interacts with two key actors of the replisome: the DNA primase (PriSL) and the replicative DNA polymerase (PolD). Using an integrative structural biology approach, combining nuclear magnetic resonance, X-ray crystallography and cryo-electron microscopy, we unveiled how RPA interacts with PriSL and PolD through two distinct surfaces of the WH domain: an evolutionarily conserved interface and a novel binding site. Finally, RPA was shown to stimulate the activity of PriSL in a WH-dependent manner. This study provides a molecular understanding of the WH-mediated regulatory activity in conserved central replication factors such as RPA, which regulate genome maintenance in Archaea and Eukaryotes.

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Martinez-Carranza, M., Vialle, L., Madru, C., Cordier, F., Dizkirici Tekpinar, A., Haouz, A., Legrand, P., Le Meur, R. A., England, P., Dulermo, R., Guijarro, I. J., Henneke, G., Sauguet, L.. 2024-04-29. Communication between DNA polymerases and Replication Protein A within the archaeal replisome. https://doi.org/10.1101/2024.04.29.591592

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