Interaction of epithelial cell membrane rafts with Paracoccidioides brasiliensis leads to fungal adhesion and Src-family kinase activation.
Membrane rafts are cholesterol- and sphingolipid-enriched cell membrane domains, which are ubiquitous in mammals and play an essential role in different cellular functions, including host cell-pathogen interaction. In this work, by using several approaches, we demonstrated the involvement of epithelial cell membrane rafts in adhesion process of the pathogenic fungus Paracoccidioides brasiliensis. This conclusion was supported by the localization of ganglioside GM1, a membrane raft marker, at P. brasiliensis-epithelial cell contact sites, and by the inhibition of this fungus adhesion to host cells pre-treated with cholesterol-extractor (methyl-beta-cyclodextrin, MbetaCD) or -binding (nystatin) agents. In addition, at a very early stage of P. brasiliensis-A549 cell interaction, this fungus promoted activation of Src-family kinases (SFKs) and extracellular signal-regulated kinase 1/2 (ERK1/2) of these epithelial cells. Whereas SFKs were partially responsible for activation of ERK1/2, membrane raft disruption with MbetaCD in A549 cells led to total inhibition of SFK activation. Taking together, these data indicate for the first time that epithelial cell membrane rafts are essential for P. brasiliensis adhesion and activation of cell signaling molecules.
Maza
Paloma K
PK
Division of Glycoconjugate Immunochemistry, Department of Biochemistry, Universidade Federal de São Paulo, Rua Botucatu, 862, Ed J Leal Prado, São Paulo, SP 04023-900, Brazil.
Straus
Anita H
AH
Toledo
Marcos S
MS
Takahashi
Helio K
HK
Suzuki
Erika
E
D000818:Animals; D002448:Cell Adhesion; D045744:Cell Line, Tumor; D002522:Chlorocebus aethiops; D002784:Cholesterol / Q000378:metabolism; D004789:Enzyme Activation; D005677:G(M1) Ganglioside / Q000378:metabolism; D054884:Host-Pathogen Interactions; D006801:Humans; D008168:Lung / Q000382:microbiology; D021962:Membrane Microdomains / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009761:Nystatin / Q000378:metabolism; D010228:Paracoccidioides / Q000254:growth & development* / Q000502:physiology; D010229:Paracoccidioidomycosis / Q000378:metabolism; D014709:Vero Cells; D047392:beta-Cyclodextrins / Q000378:metabolism; D019061:src-Family Kinases / Q000378:metabolism*
D047392:beta-Cyclodextrins; C108732:methyl-beta-cyclodextrin; D009761:Nystatin; D005677:G(M1) Ganglioside; D002784:Cholesterol; D019061:src-Family Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3