RT Journal Article SR Electronic T1 Patterns of conservation and diversification in the fungal polarization network JF bioRxiv FD Cold Spring Harbor Laboratory SP 154641 DO 10.1101/154641 A1 Eveline T. Diepeveen A1 Valérie Pourquié A1 Thies Gehrmann A1 Thomas Abeel A1 Liedewij Laan YR 2017 UL http://biorxiv.org/content/early/2017/06/23/154641.abstract AB The combined actions of proteins in networks underlie all fundamental cellular functions. Deeper insights into the dynamics of network composition across species and their functional consequences are crucial to fully understand protein network evolution. Large-scale comparative studies with high phylogenetic resolution are now feasible through the recent rise in available genomic datasets of both model and non-model species. Here we focus on the polarity network, which is universally essential for cell proliferation and studied in great detail in the model organism, Saccharomyces cerevisiae. We examine 34 proteins, directly related to cell polarization, across 200 fungal strains/species to determine evolution of the composition of the network and patterns of conservation and diversification.We observe strong protein conservation for a group of 16 core proteins: 95% of all strains/species possess at least 75% of these proteins, albeit in varying compositions. We find high levels of variation in prevalence and sequence identity in the remaining 18 proteins, resulting in distinct lineage-specific compositions of the network in the majority of strains/species. We test if the observed diversification in network composition correlates with potential underlying factors and find that lineage, lifestyle, and genetic distance co-vary with network size. Yeast, filamentous and basal unicellular fungi form distinctive groups based on these analyses, with substantial differences to their polarization network. Our study shows that evolution of the fungal polarization network is highly dynamic, even between closely related species, and that functional conservation is achieved by varying structural conservation of the fungal polarization proteins.Data Deposition Sequence alignments used are available upon request.