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bioRxiv · 10.1101/723619

Structural diversity of oligomeric β-propellers with different numbers of identical blades

Afanasieva, E.·Chaudhuri, I.·Martin, J.·Hertle, E.·Ursinus, A.·Alva, V.·Hartmann, M. D.·Lupas, A. N.
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Abstract

{beta}-Propellers arise through the amplification of a supersecondary structure element called a blade. This process produces toroids of between four and twelve repeats, which are almost always arranged sequentially in a single polypeptide chain. We found that new propellers evolve continuously by amplification from single blades. We therefore investigated whether such nascent propellers can fold as homo-oligomers before they have been fully amplified within a single chain. One-to six-bladed building blocks derived from two seven-bladed WD40 propellers yielded stable homo-oligomers with six to nine blades, depending on the size of the building block. High-resolution structures for tetramers of two blades, trimers of three blades, and dimers of four and five blades, respectively, show structurally diverse propellers and include a novel fold, highlighting the inherent flexibility of the WD40 blade. Our data support the hypothesis that subdomain-sized fragments can provide structural versatility in the evolution of new proteins.

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Afanasieva, E., Chaudhuri, I., Martin, J., Hertle, E., Ursinus, A., Alva, V., Hartmann, M. D., Lupas, A. N.. 2019-08-02. Structural diversity of oligomeric β-propellers with different numbers of identical blades. https://doi.org/10.1101/723619

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