Structural diversity of oligomeric β-propellers with different numbers of identical blades
- Max Planck Institute for Developmental Biology, Germany
Abstract
β-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.
Data availability
Diffraction data have been deposited in PDB under the accession codes 6R5X, 6R5Z, 6R5Y, and 6R60.
Article and author information
Author details
Funding
Max Planck Society
- Andrei N Lupas
Volkswagen Foundation (Life Grant 94 810)
- Andrei N Lupas
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Afanasieva et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Structural diversity of oligomeric β-propellers with different numbers of identical blades
eLife 8:e49853.
https://doi.org/10.7554/eLife.49853
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