Role of N- glycosylation on gene expression related to cell wall remodeling of Paracoccidioides brasiliensis

Abstract

Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, the most prevalent systemic mycosis in Latin America. Fungus can able to increase their pathogenicity by factors as lipids, polysaccharides and glycoproteins. Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, the most prevalent systemic mycosis in Latin America. Fungus can able to increase their pathogenicity by factors as lipids, polysaccharides and glycoproteins. Glycosylation is important for protein secretion, function, stability and immunogenicity. N-glycans linked to proteins have been characterized in many species of yeast to mammals. In P. brasiliensis yeast, N-glycans play important role in the activity of N-acetyl-²-D-glucosaminidase (NAGase) and ±-1,4-amylase produced by yeast, and are directly involved in fungal growth and morphogenesis. Due the fact of N-glycans influence on the biological activities of P. brasiliensis proteins, have motivated us to investigate the effects of N-glycosylation inhibition on regulation of the NAGase, ± and ²-1,3-glucanase, and ± -1,4-amylase, in other hands on cell wall degradation/biosynthesis related enzymes of P. brasiliensis. Therefore, we propose to do the following aims: (1) Evaluate the effect of n-glycosylation inhibition by tunicamycin on cell wall degradation/biosynthesis related enzymes of P. brasiliensis; (2) Determine the predicted sites of N-linked glycans, as well as the three-dimensional (3D) structure predicted above mentioned enzymes; (3) To compare the predicted 3D structure obtained with the predicted 3D structure of the same enzymes in other dimorphic fungi such Coccidioides immitis, Candida albicans, Blastomyces dermatitidis e Histoplasma capsulatum. Our expectation is that the achievement of these aims will allow the elucidation of the existence of a direct association between the N-glycosylation and regulation of genes that coding to proteins involved on growth, morphogenesis and pathogenicity of P. brasiliensis.