Functional characterization of an Aspergillus fumigatus calcium transporter (PmcA) that is essential for fungal infection.
Aspergillus fumigatus is a primary and opportunistic pathogen, as well as a major allergen, of mammals. The Ca(+2)-calcineurin pathway affects virulence, morphogenesis and antifungal drug action in A. fumigatus. Here, we investigated three components of the A. fumigatus Ca(+2)-calcineurin pathway, pmcA,-B, and -C, which encode calcium transporters. We demonstrated that CrzA can directly control the mRNA accumulation of the pmcA-C genes by binding to their promoter regions. CrzA-binding experiments suggested that the 5'-CACAGCCAC-3' and 5'-CCCTGCCCC-3' sequences upstream of pmcA and pmcC genes, respectively, are possible calcineurin-dependent response elements (CDREs)-like consensus motifs. Null mutants were constructed for pmcA and -B and a conditional mutant for pmcC demonstrating pmcC is an essential gene. The ΔpmcA and ΔpmcB mutants were more sensitive to calcium and resistant to manganese and cyclosporin was able to modulate the sensitivity or resistance of these mutants to these salts, supporting the interaction between calcineurin and the function of these transporters. The pmcA-C genes have decreased mRNA abundance into the alveoli in the ΔcalA and ΔcrzA mutant strains. However, only the A. fumigatus ΔpmcA was avirulent in the murine model of invasive pulmonary aspergillosis.
Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
Taísa Magnani
TM
Dinamarco
Fernanda Zanolli
FZ
Freitas
Ricardo S
RS
Almeida
Neil Andrew
NA
Brown
Thaila Fernanda
TF
dos Reis
Leandra Naira Zambelli
LN
Ramalho
Marcela
M
Savoldi
Maria Helena S
MH
Goldman
Maria Célia
MC
Bertolini
Gustavo Henrique
GH
Goldman
D000818:Animals; D001232:Aspergillus fumigatus / Q000201:enzymology* / Q000254:growth & development / Q000472:pathogenicity*; D018893:Bronchoalveolar Lavage / Q000379:methods; D020013:Calcium Signaling / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D024202:Electrophoretic Mobility Shift Assay; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal / Q000235:genetics / Q000502:physiology*; D005822:Genetic Vectors / Q000235:genetics; D051379:Mice; D053499:Plasma Membrane Calcium-Transporting ATPases / Q000235:genetics / Q000378:metabolism*; D055732:Pulmonary Aspergillosis / Q000201:enzymology / Q000382:microbiology*; D060888:Real-Time Polymerase Chain Reaction; D020218:Response Elements / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014774:Virulence / Q000235:genetics*
C530975:CrzA protein, Aspergillus fumigatus; D017931:DNA Primers; D005656:Fungal Proteins; D053499:Plasma Membrane Calcium-Transporting ATPases