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bioRxiv · 10.1101/2020.06.24.160820

A rod conformation of the Pyrococcus furiosus Rad50 coiled coil

Soh, Y.-M.·Basquin, J.·Gruber, S.
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Abstract

The Rad50-Mre11 nuclease complex plays a vital role in DNA repair in all domains of life. It recognizes and processes DNA double-strand breaks. Rad50 proteins fold into an extended structure with a ~20-60 nm long coiled coil connecting a globular ABC ATPase domain with a zinc hook dimerization domain. A published structure of an archaeal Rad50 zinc hook shows coiled coils pointing away from each other. Here we present the crystal structure of an alternate conformation displaying co-aligned coiled coils. Archaeal Rad50 may thus switch between rod-shaped and ring-like conformations as recently proposed for a bacterial homolog.

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Soh, Y.-M., Basquin, J., Gruber, S.. 2020-06-24. A rod conformation of the Pyrococcus furiosus Rad50 coiled coil. https://doi.org/10.1101/2020.06.24.160820

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