Paracoccin distribution supports its role in Paracoccidioides brasiliensis growth and dimorphic transformation

Author(s)

Oliveira, Aline Ferreira ; Fernandes, Fabricio Freitas ; Mariano, Vania Sammartino ; Almeida, Fausto ; Ruas, Luciana Pereira ; Oliveira, Leandro Licursi ; Oliver, Constance ; Jamur, Maria Celia ; Roque-Barreira, Maria Cristina

• Document type: Journal article
• Source: PLoS One; v. 12, n. 8 AUG 28 2017.
• Web of Science Citations: 1

Abstract

Paracoccidioides brasiliensis yeast was reported to express paracoccin, a GlcNAc-binding protein that displays N-acetyl-beta-D-glucosaminidase (NAGase) activity. Highly specific antiparacoccin antibodies have been previously used to examine the localization of paracoccin in yeast and inhibit its growth in vitro. In the present study, anti-paracoccin antibodies were used to characterize, by scanning confocal microscopy, the distribution of paracoccin in P. brasiliensis hyphae, transition forms from hyphae to yeast, and mature yeast. In the mycelial phase, paracoccin was detected mainly in the hyphae tips, where it demonstrated a punctate distribution, and was associated with the cell wall. During the first 48 hours after a temperature shift from 26 degrees C to 37 degrees C, paracoccin expression in the differentiating hyphae was mainly detected in the budding regions, i.e. lateral protrusions, and inside the new daughter cells. There was an increased number of chlamydoconidia that expressed a high concentration of paracoccin on their surfaces and/or in their interiors 72-96 hours after the temperature shift. After 120 hours, yeast cells were the predominant form and their cytoplasm stained extensively for paracoccin, whereas Wheat Germ Agglutinin (WGA) staining was predominant on their exterior walls. After 10 days at 37 degrees C, the interior of both mother and daughter yeast cells, as well as the budding regions, stained intensely for paracoccin. The comparison of mRNA-expression in the different fungal forms showed that PCN transcripts, although detected in all evaluated morphological forms, were higher in hypha and yeast-tohypha transition forms. In conclusion, the pattern of paracoccin distribution in all P. brasiliensis morphotypes supports prevalent beliefs that it plays important roles in fungal growth and dimorphic transformation. (AU)

• FAPESP's process: 13/10741-8 - Effect of N-glycosylation inhibition on the transcriptional and proteomic profiles of Paracoccidioides brasiliensis
• Grantee: Fausto Bruno dos Reis Almeida
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 06/60642-2 - Lectins: biological effects and pharmaceutical applications
• Grantee: Maria Cristina Roque Antunes Barreira
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 09/51197-3 - Role of N-glycans in activities developed by paracoccin
• Grantee: Fausto Bruno dos Reis Almeida
• Support Opportunities: Scholarships in Brazil - Doctorate