Analysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation

ABSTRACT The opportunistic fungal pathogen Cryptococcus neoformans causes life-threatening meningitis in immunocompromised individuals. The expression of virulence factors, including capsule and melanin, is in part regulated by the cyclic-AMP/protein kinase A (cAMP/PKA) signal transduction pathway....

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	J. M. H. Geddes, M. Caza, D. Croll, N. Stoynov, L. J. Foster, J. W. Kronstad
Formato:	article
Lenguaje:	EN
Publicado:	American Society for Microbiology 2016
Materias:	Microbiology QR1-502
Acceso en línea:	https://doaj.org/article/bee33ed7728247bfbd8597362987e60d
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:bee33ed7728247bfbd8597362987e60d
record_format	dspace
spelling	oai:doaj.org-article:bee33ed7728247bfbd8597362987e60d2021-11-15T15:49:40ZAnalysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation10.1128/mBio.01862-152150-7511https://doaj.org/article/bee33ed7728247bfbd8597362987e60d2016-03-01T00:00:00Zhttps://journals.asm.org/doi/10.1128/mBio.01862-15https://doaj.org/toc/2150-7511ABSTRACT The opportunistic fungal pathogen Cryptococcus neoformans causes life-threatening meningitis in immunocompromised individuals. The expression of virulence factors, including capsule and melanin, is in part regulated by the cyclic-AMP/protein kinase A (cAMP/PKA) signal transduction pathway. In this study, we investigated the influence of PKA on the composition of the intracellular proteome to obtain a comprehensive understanding of the regulation that underpins virulence. Through quantitative proteomics, enrichment and bioinformatic analyses, and an interactome study, we uncovered a pattern of PKA regulation for proteins associated with translation, the proteasome, metabolism, amino acid biosynthesis, and virulence-related functions. PKA regulation of the ubiquitin-proteasome pathway in C. neoformans showed a striking parallel with connections between PKA and protein degradation in chronic neurodegenerative disorders and other human diseases. Further investigation of proteasome function with the inhibitor bortezomib revealed an impact on capsule production as well as hypersusceptibility for strains with altered expression or activity of PKA. Parallel studies with tunicamycin also linked endoplasmic reticulum stress with capsule production and PKA. Taken together, the data suggest a model whereby expression of PKA regulatory and catalytic subunits and the activation of PKA influence proteostasis and the function of the endoplasmic reticulum to control the elaboration of the polysaccharide capsule. Overall, this study revealed both broad and conserved influences of the cAMP/PKA pathway on the proteome and identified proteostasis as a potential therapeutic target for the treatment of cryptococcosis. IMPORTANCE Fungi cause life-threatening diseases, but very few drugs are available to effectively treat fungal infections. The pathogenic fungus Cryptococcus neoformans causes a substantial global burden of life-threatening meningitis in patients suffering from HIV/AIDS. An understanding of the mechanisms by which fungi deploy virulence factors to cause disease is critical for developing new therapeutic approaches. We employed a quantitative proteomic approach to define the changes in the protein complement that occur upon modulating the cAMP signaling pathway that regulates virulence in C. neoformans. This approach identified a conserved role for cAMP signaling in the regulation of the ubiquitin-proteasome pathway and revealed a link between this pathway and elaboration of a major virulence determinant, the polysaccharide capsule. Targeting the ubiquitin-proteasome pathway opens new therapeutic options for the treatment of cryptococcosis.J. M. H. GeddesM. CazaD. CrollN. StoynovL. J. FosterJ. W. KronstadAmerican Society for MicrobiologyarticleMicrobiologyQR1-502ENmBio, Vol 7, Iss 1 (2016)
institution	DOAJ
collection	DOAJ
language	EN
topic	Microbiology QR1-502
spellingShingle	Microbiology QR1-502 J. M. H. Geddes M. Caza D. Croll N. Stoynov L. J. Foster J. W. Kronstad Analysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation
description	ABSTRACT The opportunistic fungal pathogen Cryptococcus neoformans causes life-threatening meningitis in immunocompromised individuals. The expression of virulence factors, including capsule and melanin, is in part regulated by the cyclic-AMP/protein kinase A (cAMP/PKA) signal transduction pathway. In this study, we investigated the influence of PKA on the composition of the intracellular proteome to obtain a comprehensive understanding of the regulation that underpins virulence. Through quantitative proteomics, enrichment and bioinformatic analyses, and an interactome study, we uncovered a pattern of PKA regulation for proteins associated with translation, the proteasome, metabolism, amino acid biosynthesis, and virulence-related functions. PKA regulation of the ubiquitin-proteasome pathway in C. neoformans showed a striking parallel with connections between PKA and protein degradation in chronic neurodegenerative disorders and other human diseases. Further investigation of proteasome function with the inhibitor bortezomib revealed an impact on capsule production as well as hypersusceptibility for strains with altered expression or activity of PKA. Parallel studies with tunicamycin also linked endoplasmic reticulum stress with capsule production and PKA. Taken together, the data suggest a model whereby expression of PKA regulatory and catalytic subunits and the activation of PKA influence proteostasis and the function of the endoplasmic reticulum to control the elaboration of the polysaccharide capsule. Overall, this study revealed both broad and conserved influences of the cAMP/PKA pathway on the proteome and identified proteostasis as a potential therapeutic target for the treatment of cryptococcosis. IMPORTANCE Fungi cause life-threatening diseases, but very few drugs are available to effectively treat fungal infections. The pathogenic fungus Cryptococcus neoformans causes a substantial global burden of life-threatening meningitis in patients suffering from HIV/AIDS. An understanding of the mechanisms by which fungi deploy virulence factors to cause disease is critical for developing new therapeutic approaches. We employed a quantitative proteomic approach to define the changes in the protein complement that occur upon modulating the cAMP signaling pathway that regulates virulence in C. neoformans. This approach identified a conserved role for cAMP signaling in the regulation of the ubiquitin-proteasome pathway and revealed a link between this pathway and elaboration of a major virulence determinant, the polysaccharide capsule. Targeting the ubiquitin-proteasome pathway opens new therapeutic options for the treatment of cryptococcosis.
format	article
author	J. M. H. Geddes M. Caza D. Croll N. Stoynov L. J. Foster J. W. Kronstad
author_facet	J. M. H. Geddes M. Caza D. Croll N. Stoynov L. J. Foster J. W. Kronstad
author_sort	J. M. H. Geddes
title	Analysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation
title_short	Analysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation
title_full	Analysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation
title_fullStr	Analysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation
title_full_unstemmed	Analysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation
title_sort	analysis of the protein kinase a-regulated proteome of <named-content content-type="genus-species">cryptococcus neoformans</named-content> identifies a role for the ubiquitin-proteasome pathway in capsule formation
publisher	American Society for Microbiology
publishDate	2016
url	https://doaj.org/article/bee33ed7728247bfbd8597362987e60d
work_keys_str_mv	AT jmhgeddes analysisoftheproteinkinasearegulatedproteomeofnamedcontentcontenttypegenusspeciescryptococcusneoformansnamedcontentidentifiesarolefortheubiquitinproteasomepathwayincapsuleformation AT mcaza analysisoftheproteinkinasearegulatedproteomeofnamedcontentcontenttypegenusspeciescryptococcusneoformansnamedcontentidentifiesarolefortheubiquitinproteasomepathwayincapsuleformation AT dcroll analysisoftheproteinkinasearegulatedproteomeofnamedcontentcontenttypegenusspeciescryptococcusneoformansnamedcontentidentifiesarolefortheubiquitinproteasomepathwayincapsuleformation AT nstoynov analysisoftheproteinkinasearegulatedproteomeofnamedcontentcontenttypegenusspeciescryptococcusneoformansnamedcontentidentifiesarolefortheubiquitinproteasomepathwayincapsuleformation AT ljfoster analysisoftheproteinkinasearegulatedproteomeofnamedcontentcontenttypegenusspeciescryptococcusneoformansnamedcontentidentifiesarolefortheubiquitinproteasomepathwayincapsuleformation AT jwkronstad analysisoftheproteinkinasearegulatedproteomeofnamedcontentcontenttypegenusspeciescryptococcusneoformansnamedcontentidentifiesarolefortheubiquitinproteasomepathwayincapsuleformation
_version_	1718427482218037248

Analysis of the Protein Kinase A-Regulated Proteome of <named-content content-type="genus-species">Cryptococcus neoformans</named-content> Identifies a Role for the Ubiquitin-Proteasome Pathway in Capsule Formation

Ejemplares similares