The Biochemical Evolution of Protein Complexes

Abstract

Over the past decade, it became evident that proteins perform critical functions as components of specialized macromolecular complexes. Here, we discuss a recent study by Wan and colleagues, which highlights the significance of protein complexes by studying their conservation in organisms separated by up to a billion years of evolution.

Keywords: Protein interactions; evolution; interactome; macromolecular complex; mass spectrometry; protein-protein interaction.

Figure 1

Phylogenetic Relationships and Protein Complex Conservation Among Yeast (Saccharomyces cerevisiae), Slime Mold (Dictyostelium discoideum), Worms (Caenorhabditis elegans), and Humans (Homo sapiens). Conserved protein complexes were determined by biochemical co-fractionation, mass spectrometry, and computational scoring [7]. Representative complexes were selected to highlight the increasing diversity from lower to higher order present-day eukaryotes. Lower order eukaryotes tend to possess highly conserved complexes containing ancient components (orange nodes) that can be traced through hundreds of millions of years (Mya) of evolution, or a mixture of old and new components (green nodes). Higher order eukaryotes often retain these protein complexes, while also possessing complexes that have acquired newer components, reflecting more-specialized functions. The evolution of ancestral complexes to present-day complexes remains to be fully understood.