Characterization of extracellular vesicles from pathogenic fungi under stress and their role in cellular communication

Abstract

Extracellular vesicles (EV) have recently been described in pathogenic fungi. In our laboratory, we have previously reported Paracoccidioides brasiliensis EV protein and lipid content, besides carbohydrate epitopes. Nowadays, we also have results of the RNA and polysaccharide EV content. Fungal EV carry components that potentially interact with the host, stimulate the immune system and are involved in pathogenesis, even by signaling from distant sites. EV signaling function between fungal cells is still unknown. The aim of this work is to characterize EV from pathogenic fungi under stress and to evaluate the role of these vesicles in cell communication, using P. brasiliensis and Candida albicans as a models. Specific aims: 1. To optimize and evaluate the effect of heat, oxidative and nitrosative stress, besides farnesol and tyrosol mediators, in EV production in P. brasiliensis and/or C. albicans. We will initially observe basic parameters, specifically, amount of sterol and protein and nucleic acid profile. 2. According to the results, we will proceed with further analyses of protein and RNA content of EV isolated from yeast cells subjected or not to selected treatments. 3. To verify if EV produced under stress are able to affect non-stressed cells. Optimize the methods of study. 4. Microscopic analysis (TEM and/or confocal) of fungal cells subjected to selected treatments, compared to untreated cells. Observation of corresponding vesicular preparations. According to results, some goals will possibly be excluded or included. The applicant and his supervisor are predicting a few months of work outside the country, in collaboration with foreign researchers. (AU)