Functional and morphological stasis during molecular evolution

✍ Scribed by Robert C. Williams

• Book ID: 102703400
• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 948 KB
• Volume: 81
• Category: Article
• ISSN: 0002-9483
• DOI: 10.1002/ajpa.1330810111

✦ Synopsis

The evolutionary distance between two sets of proteins was estimated using the techniques of Miyata and Yasunaga (1980) and Kimura (1 980). Human p,-microglobulin was compared with the homologous murine molecule, while human and equine a-globin were similarly treated. It was found that a large amount of molecular evolution has occurred in p,-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 a-globin are 0.152, 0.293, and 0.084. In spite of this molecular evolution, it is shown that murine microglo globulin 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.