[en] Several filamentous fungal species belonging to the genus Fusarium are phytopathogens commonly present in small grain cereals and are responsible for the development of the pathology Fusarium+ head blight, which leads to reductions in yield on small-grain cereal productions.Some of these species also have the capacity to synthesize secondary metabolites such as mycotoxins, under appropriate environmental conditions. These secondary metabolites contaminate crops and can be linked with toxic effects for human health. Increased knowledge about the possible effects of mycotoxins promoted the establishment of legal regulations concerning acceptable levels of certain mycotoxins in foodstuffs. Previous studies demonstrate that several abiotic factors affect fungal metabolism and influence mycotoxin production. In fact, changes in ambient pH have an effect on the production of both the mycotoxins type B trichothecens and enniatins by F.graminearum and F.avenaceum, respectively. FgPac1 was the name given to F.graminearum PacC ortholog–PacC is a known pH sensor in Aspergillus – and FavPac1 is the name given to a putative FgPac1 orthologous candidate gene in F.avenaceum. FavPac1 has been identified by bioinformatics analyses based on DNA sequence homology. In this project, we investigate whether FavPac1+has a pH-related role in enniatin production by F.avenaceum, and is a bona fide ortholog of FgPac1. For this, we take two approaches: - FavPac1 add-back assays in F. avenaceum strains FavΔPac1 in which the unique copy of FavPac1 has been removed; - Genetic complementation assays with FgPac1 in F.avenaceum strains FavΔPac1; After characterizing all mutants vs.wild-type strains for growth and production of mycotoxins, expecting the rescue of wild-type phenotypes in the add-back and complementation assays if FavPac1 is actually responsible for the observed defects and is a bona fide ortholog of PacC, respectively.

[gl] Moitas especies de fungos filamentosos pertencentes ao xénero Fusarium son fitopatoxenos comúnmente presentes en cereais de gran tamaño e son responsables do desenvolvemento da patoloxia de tordido de cabeza de Fusarium, o que conduce a un rendemento reducido nas producions de cereais de grao pequeno. Algunhas destas especies tamen tenen a capacidade de sintetizar metabolitos secundarios como as micotoxinas, en condicións ambientais adecuadas. Estes metabolitos secundarios contaminan los cultivos e poden estar relacionados con efectos toxicos sobre a saúde humana. O desenvolvemento de coñecemento sobre os posibles efectos das micotoxinas promoveu a aparición de novas normativas legais sobre niveis aceptables de certas micotoxinas nos alimentos. Estudos anteriores demostran que varios factores abióticos afectan o metabolismo dos fungos e inflúen na producción de micotoxinas. De feito, os cambios no pH ambiental tenen un efecto na capacidade de F.graminearum e F.avenaceum de biosintetizar enniatinas. FgPac1 foi o nomedado ao ortólogo PacC!en F.graminearum e FavPac1 o nome dado a un xen candidato ortólogo para FgPac1 en F.avenaceum. FavPac1 foi identificado por bioinformatica. Neste proxecto analizamos se FavPac1 ten un papel na produción de enniatinas por F. Avenaceum e se é un ortólogo de FgPac1. Para iso, adoptamos dous enfoques: -Estudos de complementación xenética de cepas de F.avenaceum nas que se eliminou a copia única de FavPac1; - Fenotipado de mutantes frente a cepas de tipo salvaxe para o crecemento e produción de micotoxinas.