RT Journal Article T1 Algal-fungal mutualism: cell recognition and maintenance ofthe symbiotic status of lichens A1 Díaz, E. M. A1 Sánchez Elordi, Elena A1 Santiago, Rocío A1 Vicente Córdoba, Carlos A1 Legaz González, María Estrella AB Lichens are specific symbiotic associations between photosynthetic algae or cyanobacteria and heterotrophic fungi forming a double entity in which both components coexist. Specificity required for the lichen establishment can be defined in this context as the preferential, but not exclusive, association of a biont with another, since the algal factor susceptible to be recognized is an inducible protein. Recognition of compatible algal cells is performed by specific lectins produced and secreted by the potential mycobiont. Some lectins from phycolichens and cyanolichens are glycosylated arginases which bind to an algal cell wall receptor, identified as a a-1, 4-polygalactosylated urease. However, other ligands exist which bind other lectins specific for mannose or glucose. This implies that, after recognition of a potential, compatible partner, other fungal lectins could determine the final success of the association. Since the fungus can parasitize non - recognized partners during the development of the association, the success after the first contact needs of a set of algal cells, the number of which was sufficient to prevent that the death of a certain number of them makes fail the symbiosis. Fungal lectins act as chemo tactic factors in such a way that algae and cyanobacteria move towards the hyphae, to acquire that critical size of the colony, by means of successive contractions and relaxation of the actomyosin cytoskeleton in absence of any motile appendages. PB JSciMed Central SN 2378-931X YR 2016 FD 2016-08-22 LK https://hdl.handle.net/20.500.14352/18468 UL https://hdl.handle.net/20.500.14352/18468 LA eng NO Universidad Complutense de Madrid DS Docta Complutense RD 6 jun 2025