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β-Keratins in crocodiles reveal amino acid homology with avian keratins

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Abstract

The DNA sequences encoding β-keratin have been obtained from Marsh Mugger (Crocodylus palustris) and Orinoco Crocodiles (Crocodylus intermedius). Through the deduced amino acid sequence, these proteins are rich in glycine, proline and serine. The central region of the proteins are composed of two beta-folded regions and show a high degree of identity with β-keratins of aves and squamates. This central part is thought to be the site of polymerization to build the framework of β-keratin filaments. It is believed that the β-keratins in reptiles and birds share a common ancestry. Near the C-terminal, these β-keratins contain a peptide rich in glycine-X and glycine-X-X, and the distinctive feature of the region is some 12-amino acid repeats, which are similar to the 13-amino acid repeats in chick scale keratin but absent from avian feather keratin. From our phylogenetic analysis, the β-keratins in crocodile have a closer relationship with avian keratins than the other keratins in reptiles.

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Acknowledgments

This work was financially supported by the National Natural Science Foundation of China (NSFC, no. 30770312 and30470244), the Foundation for Leader of Scholarship in Anhui and the Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province.

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Authors and Affiliations

  1. College of Life Sciences, and Key Laboratory for Conservation and Exploitation of Biological Resource in Anhui Province, Anhui Normal University, 241000, Wuhu, China

    Changjiang Ye, Xiaobing Wu & Peng Yan

  2. Sackler Institute for Comparative Genomics, American Museum of Natural History, Manhattan, NY, 10024, USA

    George Amato

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  1. Changjiang Ye
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  2. Xiaobing Wu
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  3. Peng Yan
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  4. George Amato
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Correspondence to Xiaobing Wu.

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Ye, C., Wu, X., Yan, P. et al. β-Keratins in crocodiles reveal amino acid homology with avian keratins. Mol Biol Rep 37, 1169–1174 (2010). https://doi.org/10.1007/s11033-009-9480-z

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  • DOI: https://doi.org/10.1007/s11033-009-9480-z

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