Functional and morphological stasis during molecular evolution.

R C Williams

doi:10.1002/ajpa.1330810111

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Functional and morphological stasis during molecular evolution.

R C Williams

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Abstract

The evolutionary distance between two sets of proteins was estimated using the techniques of Miyata and Yasunaga (1980) and Kimura (1980). Human beta 2-microglobulin was compared with the homologous murine molecule, while human and equine alpha-globin were similarly treated. It was found that a large amount of molecular evolution has occurred in beta 2-microglobulin since its divergence from the common ancestor of mice and humans. Kimura's estimate of evolutionary distance, K, is 0.353, while those of Miyata and Yasunaga are KS = 0.708 and KA = 0.171. The respective values for human and equine alpha-globin are 0.152, 0.293, and 0.084. In spite of this molecular evolution, it is shown that murine beta 2-microglobulin can effect the expression of HLA class I antigens on the surface of human-mouse hybrid cells and that the tertiary structures of human and equine deoxyhemoglobin are nearly identical. These observations are discussed in the light of Kimura's theory of neutral allelic drift.

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Amino Acid Sequence Animals Base Sequence Biological Evolution Codon DNA Globins Horses Humans Mice Molecular Sequence Data Protein Conformation beta 2-Microglobulin Comparative Study Journal Article

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R C Williams. 1990. Functional and morphological stasis during molecular evolution.. https://doi.org/10.1002/ajpa.1330810111

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