title: The hemibiotrophic cacao pathogen Moniliophthora perniciosa depends on a mitochondrial alternative oxidase for biotrophic development.
abstract: The tropical pathogen Moniliophthora perniciosa causes witches' broom disease in cacao. As a hemibiotrophic fungus, it initially colonizes the living host tissues (biotrophic phase), and later grows over the dead plant (necrotrophic phase). Little is known about the mechanisms that promote these distinct fungal phases or mediate the transition between them. An alternative oxidase gene (Mp-aox) was identified in the M. perniciosa genome and its expression was analyzed througout the fungal life cycle. In addition, the effects of inhibitors of the cytochrome-dependent respiratory chain (CRC) and alternative oxidase (AOX) were evaluated on the in vitro development of M. perniciosa. Larger numbers of Mp-aox transcripts were observed in the biotrophic hyphae, which accordingly showed elevated sensitivity to AOX inhibitors. More importantly, the inhibition of CRC prevented the transition from the biotrophic to the necrotrophic phase, and the combined use of a CRC and AOX inhibitor completely halted fungal growth. On the basis of these results, a novel mechanism is presented in which AOX plays a role in the biotrophic development of M. perniciosa and regulates the transition to its necrotrophic stage. Strikingly, this model correlates well with the infection strategy of animal pathogens, particularly Trypanosoma brucei, which uses AOX as a strategy for pathogenicity.
authors.affiliation: Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Daniela P T
authors.initials: DPT
authors.lastname: Thomazella
authors.affiliation: Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Paulo José P L
authors.initials: PJPL
authors.lastname: Teixeira
authors.affiliation: Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Halley C
authors.initials: HC
authors.lastname: Oliveira
authors.affiliation: Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Elzira E
authors.initials: EE
authors.lastname: Saviani
authors.affiliation: Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Johana
authors.initials: J
authors.lastname: Rincones
authors.affiliation: Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Isabella M
authors.initials: IM
authors.lastname: Toni
authors.affiliation: Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Reis
authors.affiliation: Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Odalys
authors.initials: O
authors.lastname: Garcia
authors.affiliation: Sustainable Perennial Crops Laboratory, USDA-ARS, 10300 Baltimore Ave., Bldg. 001, Beltsville, MD 20705-2350, USA.
authors.forename: Lyndel W
authors.initials: LW
authors.lastname: Meinhardt
authors.affiliation: Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Ione
authors.initials: I
authors.lastname: Salgado
authors.affiliation: Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6109, Campinas, SP 13083-970, Brazil.
authors.forename: Gonçalo A G
authors.initials: GAG
authors.lastname: Pereira
mesh_terms: D000363:Agaricales / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D002099:Cacao / Q000382:microbiology*; D015870:Gene Expression; D054884:Host-Pathogen Interactions; D008689:Methacrylates; D008928:Mitochondria / Q000201:enzymology; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism*; D025282:Mycelium / Q000254:growth & development; D009569:Nitric Oxide / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D010935:Plant Diseases / Q000382:microbiology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D011743:Pyrimidines; D012457:Salicylamides; D000073739:Strobilurins; D015854:Up-Regulation; D000099188:Alternative Oxidase
chemical_list: D008689:Methacrylates; D024101:Mitochondrial Proteins; D009569:Nitric Oxide; D010088:Oxidoreductases; D010940:Plant Proteins; D011743:Pyrimidines; D012457:Salicylamides; D000073739:Strobilurins; D000099188:Alternative Oxidase; C005703:salicylhydroxamic acid; C087670:azoxystrobin