title: Evidence for the robustness of protein complexes to inter-species hybridization.
abstract: Despite the tremendous efforts devoted to the identification of genetic incompatibilities underlying hybrid sterility and inviability, little is known about the effect of inter-species hybridization at the protein interactome level. Here, we develop a screening platform for the comparison of protein-protein interactions (PPIs) among closely related species and their hybrids. We examine in vivo the architecture of protein complexes in two yeast species (Saccharomyces cerevisiae and Saccharomyces kudriavzevii) that diverged 5-20 million years ago and in their F1 hybrids. We focus on 24 proteins of two large complexes: the RNA polymerase II and the nuclear pore complex (NPC), which show contrasting patterns of molecular evolution. We found that, with the exception of one PPI in the NPC sub-complex, PPIs were highly conserved between species, regardless of protein divergence. Unexpectedly, we found that the architecture of the complexes in F1 hybrids could not be distinguished from that of the parental species. Our results suggest that the conservation of PPIs in hybrids likely results from the slow evolution taking place on the very few protein residues involved in the interaction or that protein complexes are inherently robust and may accommodate protein divergence up to the level that is observed among closely related species.
authors.affiliation: Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Pavillon Charles-Eugène-Marchand, Université Laval, Québec City, Canada.
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Leducq
authors.forename: Guillaume
authors.initials: G
authors.lastname: Charron
authors.forename: Guillaume
authors.initials: G
authors.lastname: Diss
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gagnon-Arsenault
authors.forename: Alexandre K
authors.initials: AK
authors.lastname: Dubé
authors.forename: Christian R
authors.initials: CR
authors.lastname: Landry
mesh_terms: D017124:Conserved Sequence; D019143:Evolution, Molecular; D006824:Hybridization, Genetic; D046912:Multiprotein Complexes / Q000235:genetics; D022022:Nuclear Pore / Q000235:genetics*; D060066:Protein Interaction Maps; D012319:RNA Polymerase II / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013045:Species Specificity
chemical_list: D046912:Multiprotein Complexes; D012319:RNA Polymerase II