title: Protein kinase C overexpression suppresses calcineurin-associated defects in Aspergillus nidulans and is involved in mitochondrial function.
abstract: In filamentous fungi, intracellular signaling pathways which are mediated by changing calcium levels and/or by activated protein kinase C (Pkc), control fungal adaptation to external stimuli. A rise in intracellular Ca2+ levels activates calcineurin subunit A (CnaA), which regulates cellular calcium homeostasis among other processes. Pkc is primarily involved in maintaining cell wall integrity (CWI) in response to different environmental stresses. Cross-talk between the Ca2+ and Pkc-mediated pathways has mainly been described in Saccharomyces cerevisiae and in a few other filamentous fungi. The presented study describes a genetic interaction between CnaA and PkcA in the filamentous fungus Aspergillus nidulans. Overexpression of pkcA partially rescues the phenotypes caused by a cnaA deletion. Furthermore, CnaA appears to affect the regulation of a mitogen-activated kinase, MpkA, involved in the CWI pathway. Reversely, PkcA is involved in controlling intracellular calcium homeostasis, as was confirmed by microarray analysis. Furthermore, overexpression of pkcA in a cnaA deletion background restores mitochondrial number and function. In conclusion, PkcA and CnaA-mediated signaling appear to share common targets, one of which appears to be MpkA of the CWI pathway. Both pathways also regulate components involved in mitochondrial biogenesis and function. This study describes targets for PkcA and CnaA-signaling pathways in an A. nidulans and identifies a novel interaction of both pathways in the regulation of cellular respiration.
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Colabardini
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Laure Nicolas Annick
authors.initials: LN
authors.lastname: Ries
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Neil Andrew
authors.initials: NA
authors.lastname: Brown
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Marcela
authors.initials: M
authors.lastname: Savoldi
authors.affiliation: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Taísa Magnani
authors.initials: TM
authors.lastname: Dinamarco
authors.forename: Marcia Regina
authors.initials: MR
authors.lastname: von Zeska Kress
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Marcia Regina
authors.initials: MR
authors.lastname: von Zeska
authors.affiliation: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Maria Helena S
authors.initials: MH
authors.lastname: Goldman
authors.affiliation: Laboratório Nacional de Ciência e Tecnologia do Bioetanol - CTBE, Campinas, São Paulo, Brazil; Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Gustavo Henrique
authors.initials: GH
authors.lastname: Goldman
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics; D002118:Calcium / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D006706:Homeostasis; D008928:Mitochondria / Q000378:metabolism / Q000502:physiology*; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D017434:Protein Structure, Tertiary; D015398:Signal Transduction
chemical_list: D005656:Fungal Proteins; D011493:Protein Kinase C; C120817:calcineurin phosphatase; D010744:Phosphoric Monoester Hydrolases; D002118:Calcium