Molecular Evolution of Aerobic Energy in Primates: The Cytochrome bc1 Complex

Wayne State University, Detroit MI

Investigators

Abstract

Adaptive changes in oxidative energy metabolism may be a key process in the origins of humankind. Subunits of cytochrome c oxidase, the terminal enzyme complex in the electron transport chain, and cytochrome c, the electron carrier between cytochrome bc1 and cytochrome oxidase, were previously shown to have both undergone periods of rapid amino acid substitutions in primates. These studies will now be extended to cytochrome bc1, an 11-subunit complex. Two problems will be addressed whose solutions will help provide insights into the evolution and function of cytochrome bc1 and its potential role in anthropoid primates: (1) Cytochrome bc1 subunit genes and also cytochrome c will be examined to determine whether the encoded proteins underwent bursts of rapid amino acid substitutions in lineages leading to the anthropoid primates. (2) Positively selected changes in primates will be tested as to whether they take place not only via amino acid coding region changes but also via regulatory changes in the elements that control expression of the genes. This work will characterize some of the important genetic changes that allowed the emergence of the large-brained primates.