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Evolutionary biology

A ratchet for protein complexity

Molecular machines containing related protein subunits are common in cells. Reconstruction of ancient proteins suggests that this type of complexity can evolve in the absence of any initial selective advantage. See Letter p.360

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Figure 1: Evolution of complexity in a protein ring.


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    *This article and the paper1 under discussion were published online on 8 January 2012.


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Correspondence to W. Ford Doolittle.

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Doolittle, W. A ratchet for protein complexity. Nature 481, 270–271 (2012).

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