Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes

Fruiting bodies (sporocarps, sporophores or basidiomata) of mushroom-forming fungi (Agaricomycetes) are among the most complex structures produced by fungi. Unlike vegetative hyphae, fruiting bodies grow determinately and follow a genetically encoded developmental program that orchestrates their growth, tissue differentiation and sexual sporulation. In spite of more than a century of research, our understanding of the molecular details of fruiting body morphogenesis is still limited and a general synthesis on the genetics of this complex process is lacking. In this paper, we aim at a comprehensive identification of conserved genes related to fruiting body morphogenesis and distil novel functional hypotheses for functionally poorly characterised ones. As a result of this analysis, we report 921 conserved developmentally expressed gene families, only a few dozens of which have previously been reported to be involved in fruiting body development. Based on literature data, conserved expression patterns and functional annotations, we provide hypotheses on the potential role of these gene families in fruiting body development, yielding the most complete description of molecular processes in fruiting body morphogenesis to date. We discuss genes related to the initiation of fruiting, differentiation, growth, cell surface and cell wall, defence, transcriptional regulation as well as signal transduction. Based on these data we derive a general model of fruiting body development, which includes an early, proliferative phase that is mostly concerned with laying out the mushroom body plan (via cell division and differentiation), and a second phase of growth via cell expansion as well as meiotic events and sporulation. Altogether, our discussions cover 1 480 genes of Coprinopsis cinerea, and their orthologs in Agaricus bisporus, Cyclocybe aegerita, Armillaria ostoyae, Auriculariopsis ampla, Laccaria bicolor, Lentinula edodes, Lentinus tigrinus, Mycena kentingensis, Phanerochaete chrysosporium, Pleurotus ostreatus, and Schizophyllum commune, providing functional hypotheses for ~10 % of genes in the genomes of these species. Although experimental evidence for the role of these genes will need to be established in the future, our data provide a roadmap for guiding functional analyses of fruiting related genes in the Agaricomycetes. We anticipate that the gene compendium presented here, combined with developments in functional genomics approaches will contribute to uncovering the genetic bases of one of the most spectacular multicellular developmental processes in fungi. Citation: Nagy LG, Vonk PJ, Künzler M, Földi C, Virágh M, Ohm RA, Hennicke F, Bálint B, Csernetics Á, Hegedüs B, Hou Z, Liu XB, Nan S, M. Pareek M, Sahu N, Szathmári B, Varga T, Wu W, Yang X, Merényi Z (2023). Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes. Studies in Mycology 104: 1-85. doi: 10.3114/sim.2022.104.01.

Crossreactivity of hemolytic and hemagglutinating proteins in the coelomic fluid of lumbricidae (Annelida)

Oligospecific antisera against the hemolytic and hemagglutinating compounds of the coelomic fluid (CF) of the earthworm species Eisenia fetida, Lumbricus terrestris and Aporrectodea caliginosa were prepared. The proteins were bound to the membranes of erythrocytes and injected into rabbits. By the use of these antisera the following results were obtained: 1) The antisera RaL T and RaAC reached a titer of 1:64,000, the detection limit of RaEF was 1:512,000. RaEF was demonstrated to be oligospecific only against three hemolytic proteins by Western blotting. 2) RaEF is able to inhibit the biological activity not only of hemolysins (E. fetida, A. caliginosa) but also of hemagglutinins (L. terrestris, L. rubellus, D. rubidus). 3) Complex carbohydrates, but not simple sugar compounds, are able to inhibit hemolytic and agglutinating activities in the CF of the investigated species. Fet. and alpha 1ac. GP were demonstrated to be strong inhibitors both of the hemolytic and of the hemagglutinating activity, whereas N-acetylglucosamine was only able to inhibit the hemagglutinating activity. 4) The investigated compounds were shown to crossreact in ELISA experiments. 5) By the use of Western blotting, the crossreacting molecules in the CF of the investigated lumbricid species were identified.