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bioRxiv · 10.1101/519595

Structural basis of HMCES interactions with DNA reveals multivalent substrate recognition

Halabelian, L.·Ravichandran, M.·Li, Y.·Zheng, H.·Aravind, L.·Rao, A.·Arrowsmith, C. H.
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Abstract

HMCES can covalently crosslink to abasic sites in single-stranded DNA at stalled replication forks to prevent genome instability. Here, we report crystal structures of the HMCES SRAP domain in complex with DNA-damage substrates, revealing interactions with both single-stranded and duplex segments of 3 overhang DNA. HMCES may also bind gapped DNA and 5 overhang structures to align single stranded abasic sites for crosslinking to the conserved Cys2 of its catalytic triad.

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Halabelian, L., Ravichandran, M., Li, Y., Zheng, H., Aravind, L., Rao, A., Arrowsmith, C. H.. 2019-01-13. Structural basis of HMCES interactions with DNA reveals multivalent substrate recognition. https://doi.org/10.1101/519595

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