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Lipzen, A.

Publications and source records attributed to Lipzen, A..

3 recordsLinked to original sources

Transcriptomic atlas of mushroom development highlights an independent origin of complex multicellularity

We constructed a reference atlas of mushroom formation based on developmental transcriptome data of six species and comparisons of >200 whole genomes, to elucidate the core genetic program of complex multicellularity and fruiting body development in mushroom-forming fungi (Agaricomycetes). Nearly 300 conserved gene families and >70 functional groups contained developmentally regulated genes from five to six species, covering functions related to fungal cell wall (FCW) remodeling, targeted protein degradation, signal transduction, adhesion and small secreted proteins (including effector-like orphan genes). Several of these families, including F-box proteins, protein kinases and cadherin-like proteins, showed massive expansions in Agaricomycetes, with many convergently expanded in multicellular plants and/or animals too, reflecting broad genetic convergence among independently evolved complex multicellular lineages. This study provides a novel entry point to studying mushroom development and complex multicellularity in one of the largest clades of complex eukaryotic organisms.

evolutionary biology

Integrative visual omics of the white-rot fungus Polyporus brumalis exposes the biotechnological potential of its oxidative enzymes for delignifying raw plant biomass.

White-rot fungi are wood decayers able to degrade all polymers from lignocellulosic biomass including cellulose, hemicelluloses, and lignin. The white-rot fungus Polyporus brumalis efficiently breaks down lignin and is regarded as having a high potential for the initial treatment of plant biomass in its conversion to bio-energy. We performed integrative multi-omics analyses by combining data from the fungal genome, transcriptomes, and secretomes. We found the fungus possessed an unexpectedly large set of genes coding for enzymes related to lignin degradation, and that these were highly expressed and massively secreted under solid-state fermentation conditions. The examination of interrelated multi-omics patterns revealed the coordinated regulation of lignin-active peroxidases and H2O2-generating enzymes along with the activation of cellular mechanisms for detoxification, which combined to result in the efficient lignin breakdown by the fungus.\n\nImportancePlant biomass conversion for green chemistry and bio-energy is a current challenge for a modern sustainable bioeconomy. The complex polyaromatic lignin polymers in raw biomass feedstocks (i.e. agriculture and forestry by-products) are major obstacles for biomass conversions. From a biotechnological aspect, these compounds could be a potential source of aromatic platform molecules for bio-based polymers. Here we describe the extraordinary ability of Polyporus brumalis for lignin degradation using its enzymatic arsenal to break down wheat straw, a lignocellulosic substrate that is considered as a biomass feedstock worldwide. We observed unusual expansions of gene families coding for; 1) Class II peroxidases involved in lignin degradation; and 2) GMC oxidoreductases/dehydrogenases involved in generating the hydrogen peroxide required for lignin peroxidase activity. Our findings suggested the fungus massively mobilizes this oxidative machinery during growth on wheat straw. Overall, we identified sets of co-regulated enzymes, which could potentially augment the efficiency of biotechnological plant biomass conversions.

bioengineering

Genome expansion and lineage-specific genetic innovations in the world’s largest organisms (Armillaria)

Armillaria species are both devastating forest pathogens and some of the largest terrestrial organisms on Earth. They forage for hosts and achieve immense colony sizes using rhizomorphs, root-like multicellular structures of clonal dispersal. Here, we sequenced and analyzed genomes of four Armillaria species and performed RNA-Seq and quantitative proteomic analysis on seven invasive and reproductive developmental stages of A. ostoyae. Comparison with 22 related fungi revealed a significant genome expansion in Armillaria, affecting several pathogenicity-related genes, lignocellulose degrading enzymes and lineage-specific genes likely involved in rhizomorph development. Rhizomorphs express an evolutionarily young transcriptome that shares features with the transcriptomes of fruiting bodies and vegetative mycelia. Several genes show concomitant upregulation in rhizomorphs and fruiting bodies and shared cis-regulatory signatures in their promoters, providing genetic and regulatory insights into complex multicellularity in fungi. Our results suggest that the evolution of the unique dispersal and pathogenicity mechanisms of Armillaria might have drawn upon ancestral genetic toolkits for wood-decay, morphogenesis and complex multicellularity.

evolutionary biology