Seminar with Veera Tuovinen Nogerius on lichen symbiosis

Veera Tuovinen Nogerius is a researcher at Department of Ecology and Genetics; Evolutionary Biologyapplies, Uppsala University. She uses advanced microscopy and genomics to push the boundaries of what we know about lichen symbiosis.

A structurally chimeric lichen formed by two distantly related filamentous fungi

Lichen symbiosis, as a lifestyle, has emerged multiple times during fungal evolution. One of the central dogmas in lichen biology is that the majority of thallus biomass is contributed by a single filamentous fungus and one dominant photobiont, often in a roughly 10:1 cellular ratio. In this seminar, I will present our recent discovery of a lichen in which two distantly related filamentous fungi coexist in near-equal abundance, revealed throguh the integration of genomic data with advanced microscopy. We show that the fungi are intricately interwoven throughout the thallus with no visible signs of antagonism, both reproduce sexually, and both associate closely with the photobiont. The results represent a novel interaction motif in lichens, with implications for the understanding of lichen symbiosis as well as lichen nomenclature. These findings highlight how little we still know about the ways in which lichen symbionts can be spatially organized.