Infiltration of chitin by protein coacervates defines the squid beak mechanical gradient.

@article{Tan2015InfiltrationOC,
  title={Infiltration of chitin by protein coacervates defines the squid beak mechanical gradient.},
  author={Yerpeng Tan and Shawn Hoon and Paul A. Guerette and Wei Wei and Ali Ghadban and Cai Hao and Ali Miserez and J. Herbert Waite},
  journal={Nature chemical biology},
  year={2015},
  volume={11 7},
  pages={
          488-95
        }
}
The beak of the jumbo squid Dosidicus gigas is a fascinating example of how seamlessly nature builds with mechanically mismatched materials. A 200-fold stiffness gradient begins in the hydrated chitin of the soft beak base and gradually increases to maximum stiffness in the dehydrated distal rostrum. Here, we combined RNA-Seq and proteomics to show that the beak contains two protein families. One family consists of chitin-binding proteins (DgCBPs) that physically join chitin chains, whereas the… 

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