%0 Journal Article
%T Phylogenetic diversity of stress signalling pathways in fungi
%A Elissavet Nikolaou
%A Ino Agrafioti
%A Michael Stumpf
%A Janet Quinn
%A Ian Stansfield
%A Alistair JP Brown
%J BMC Evolutionary Biology
%D 2009
%I BioMed Central
%R 10.1186/1471-2148-9-44
%X The fungi displayed significant variation in their resistance to osmotic (NaCl and sorbitol), oxidative (H2O2 and menadione) and cell wall stresses (Calcofluor White and Congo Red). There was no strict correlation between fungal phylogeny and stress resistance. Rather, the human pathogens tended to be more resistant to all three types of stress, an exception being the sensitivity of Candida albicans to the cell wall stress, Calcofluor White. In contrast, the plant pathogens were relatively sensitive to oxidative stress. The degree of conservation of osmotic, oxidative and cell wall stress signalling pathways amongst the eighteen fungal species was examined. Putative orthologues of functionally defined signalling components in Saccharomyces cerevisiae were identified by performing reciprocal BLASTP searches, and the percent amino acid identities of these orthologues recorded. This revealed that in general, central components of the osmotic, oxidative and cell wall stress signalling pathways are relatively well conserved, whereas the sensors lying upstream and transcriptional regulators lying downstream of these modules have diverged significantly. There was no obvious correlation between the degree of conservation of stress signalling pathways and the resistance of a particular fungus to the corresponding stress.Our data are consistent with the hypothesis that fungal stress signalling components have undergone rapid recent evolution to tune the stress responses in a niche-specific fashion.Microbes require robust stress responses to survive changing environments, and in particular, pathogenic microbes must mount effective responses to counter the defences of their host. The cellular and molecular responses to stress involve both acute and adaptive phases. Acute responses generally attempt to minimise the damage caused by harmful effects of a stress, such as the immediate physico-mechanical forces imposed by an osmotic stress [1]. In contrast, adaptive responses genera
%U http://www.biomedcentral.com/1471-2148/9/44