Functional characterization of the Aspergillus fumigatus PHO80 homologue
Contribuinte(s) |
UNIVERSIDADE DE SÃO PAULO |
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Data(s) |
19/10/2012
19/10/2012
2008
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Resumo |
Phosphate is an ion that is essential for fungal growth. The systems for inorganic phosphate (Pi) acquisition in eukaryotic cells (PHO) have been characterized as a low-affinity (that assures a supply of Pi at normal or high external Pi concentrations) and a high-affinity (activated in response to Pi starvation). Here, as an initial step to understand the PHO pathway in Aspergillus fumigatus, we characterized the PH080 homologue, PhoB(PHO80). We show that the Delta phoB(PHO80) mutant has a polar growth defect (i.e., a delayed germ tube emergence) and, by phenotypic and phosphate uptake analyses, establish a link between PhoB(PHO80), calcineurin and calcium metabolism. Microarray hybridizations carried out with RNA obtained from wild-type and Delta phoB(PHO80) mutant cells identify Afu4g03610 (phoD(PHO84)), Afu7g06350 (phoE(PHO89)), Afu4g06020 (phoC(PHO81)), and Afu2g09040 (vacuolar transporter Vtc4) as more expressed both in the Delta phoB(PHO80) mutant background and under phosphate-limiting conditions of 0.1 mM P-i. Epifluorescence microscopy revealed accumulation of poly-phosphate in Delta phoB(PHO80) vacuoles, which was independent of extracellular phosphate concentration. Surprisingly, a phoD(PHO84) deletion mutant is indistinguishable phenotypically from the corresponding wild-type strain. mRNA analyses suggest that protein kinase A absence supports the expression of PHO genes in A. fumigatus. Furthermore, Delta phoB(PHO80) and Delta phoD(PHO84) mutant are fully virulent in a murine low dose model for invasive aspergillosis. (C) 2008 Elsevier Inc. All rights reserved. |
Identificador |
FUNGAL GENETICS AND BIOLOGY, v.45, n.7, p.1135-1146, 2008 1087-1845 http://producao.usp.br/handle/BDPI/20085 10.1016/j.fgb.2008.04.001 |
Idioma(s) |
eng |
Publicador |
ACADEMIC PRESS INC ELSEVIER SCIENCE |
Relação |
Fungal Genetics and Biology |
Direitos |
restrictedAccess Copyright ACADEMIC PRESS INC ELSEVIER SCIENCE |
Palavras-Chave | #Aspergillus fumigatus #inorganic phosphate acquisition #PHO80 #protein kinase A #PROTEIN-KINASE-A #CYCLIN-DEPENDENT KINASE #SACCHAROMYCES-CEREVISIAE #USTILAGO-MAYDIS #PHOSPHATE ACQUISITION #REGULATES DEVELOPMENT #NIDULANS #GENE #YEAST #VIRULENCE #Genetics & Heredity #Mycology |
Tipo |
article original article publishedVersion |