Molecular Evolution of The Keratin‐associated Protein Gene Family

Abstract

Hair, unique to mammals, plays a profound role in the heat retention within homoiotherms and presumably contributes significantly to the rapid radiation of mammals to become the dominant terrestrial vertebrate on earth. Keratin‐associated protein (KRTAP) is one of the major component of hair. Phylogenetic analysis of the KRTAP gene family could illuminate the origin and evolution of mammalian hair to some extent. Furthermore, study of KRTAP gene family will provide important information on the hair‐related disorders.

Key concepts

  • KRTAP is one of the major components of mammalian hair. To some extent, a relation lies between the molecular evolution of KRTAP gene family and evolution of hair. Comparative genomic and polymorphism data of the KRTAP gene family will provide important information on the hair disorders in the human populations.

Keywords: keratin‐associated protein; KRTAP; gene family; molecular evolution

Figure 1.

Summary of the evolution of the KRTAP gene repertoires in eight mammals. Major events in the evolution of the KRTAP gene family are summarized. The number of KRTAP genes in each species is indicated on the right with ‘all’, ‘HS’ and ‘HGT’ indicating patterns for all, high cysteine and high glycine‐tyrosine KRTAPs, respectively. The columns represent the numbers of intact, interrupted and all genes and the percentage of pseudogenization calculated as the ratio of number of disrupted gene to all genes, for each of the categories of genes. Stars in the phylogeny indicate the origin of subfamilies, while circles indicate losses. Reproduced from Wu et al..

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Further Reading

Grus WE, Shi P, Zhang YP et al. (2005) Dramatic variation of the vomeronasal pheromone receptor gene repertoire among five orders of placental and marsupial mammals. Proceedings of the National Academy of Sciences of the USA 102: 5767–5772.

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Shi P and Zhang J (2007) Comparative genomic analysis identifies an evolutionary shift of vomeronasal receptor gene repertoires in the vertebrate transition from water to land. Genome Research 17(2): 166–174.

Shi P, Zhang J, Yang H et al. (2003) Adaptive diversification of bitter taste receptor genes in Mammalian evolution. Molecular Biology and Evolution 20: 805–814.

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Wu, Dong‐Dong, and Zhang, Ya‐Ping(Sep 2009) Molecular Evolution of The Keratin‐associated Protein Gene Family. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0021767]