Disease relevance of Ascomycota

• Ascospores from the phytopathogenic fungus Sclerotinia sclerotiorum were transformed to hygromycin B resistance by co-cultivation with Agrobacterium tumefaciens [1].
• Over a four-year period, 25 304 fungal isolates (approximately 97% ascomycetes and 3% basidiomycetes), were screened for antibacterial activity against methicillin-resistant Staphylococcus aureus [2].

High impact information on Ascomycota

• The HM1 gene in maize controls both race-specific resistance to the fungus Cochliobolus carbonum race 1 and expression of the NADPH (reduced form of nicotinamide adenine dinucleotide phosphate)-dependent HC toxin reductase (HCTR), which inactivates HC toxin, a cyclic tetrapeptide produced by the fungus to permit infection [3].
• A mitogen-activated protein kinase pathway modulates the expression of two cellulase genes in Cochliobolus heterostrophus during plant infection [4].
• A gene, HDC1, related to the Saccharomyces cerevisiae histone deacetylase (HDAC) gene HOS2, was isolated from the filamentous fungus Cochliobolus carbonum, a pathogen of maize that makes the HDAC inhibitor HC-toxin [5].
• An ortholog of SNF1, ccSNF1, was isolated from the maize pathogen Cochliobolus carbonum, and ccsnf1 mutants of HC toxin-producing (Tox2(+)) and HC toxin-nonproducing (Tox2(-)) strains were created by targeted gene replacement [6].
• Effective pathogenesis by the fungus Sclerotinia sclerotiorum requires the secretion of oxalic acid [7].

Biological context of Ascomycota

• A mitogen-activated protein kinase of the corn leaf pathogen Cochliobolus heterostrophus is involved in conidiation, appressorium formation, and pathogenicity: diverse roles for mitogen-activated protein kinase homologs in foliar pathogens [8].
• Body plan evolution of ascomycetes, as inferred from an RNA polymerase II phylogeny [9].
• The system employs the plasmid pHIS, which contains a bacterial hygromycin B phosphotransferase gene linked to Cochliobolus heterostrophus regulatory sequences (B. G. Turgeon, R. C. Garber, and O. C. Yoder, Mol. Cell. Biol. 7:3297-3305, 1987) [10].
• The deduced amino acid sequence of the laccase was shown to have high homology with laccases from other ascomycetes [11].
• Molecular analysis of the split cox1 gene from the Basidiomycota Agrocybe aegerita: relationship of its introns with homologous Ascomycota introns and divergence levels from common ancestral copies [12].

Anatomical context of Ascomycota

• Identification of progesterone binding sites in the plasma membrane of the filamentous fungus Cochliobolus lunatus [13].
• Pyruvate decarboxylase filaments are associated with the cortical cytoskeleton of asci and spores over the sexual cycle of filamentous ascomycetes [14].
• Testosterone and 4-androstene-3,17-dione (androstenedione) binding proteins were found in the cytosol of Cochliobolus lunatus, a filamentous fungus [15].

Associations of Ascomycota with chemical compounds

• Inhibition of maize histone deacetylases by HC toxin, the host-selective toxin of Cochliobolus carbonum [16].
• The maize Hm1 gene encoding the NADPH-dependent HC-toxin reductase is capable of detoxifying HC-toxin of fungus Cochliobolus carbonum [17].
• The regulator of nitrate assimilation in ascomycetes is a dimer which binds a nonrepeated, asymmetrical sequence [18].
• Furthermore, fludioxonil activates Hog1-type MAPKs in the plant pathogenic fungi Cochliobolus heterostrophus and Botrytis cinerea [19].
• However, physiological and genetical evidence indicates that adenine deaminases are present in the ascomycetes [20].

Gene context of Ascomycota

• The pad4-1 mutation caused reduced camalexin synthesis in response to PsmES4326 infection, but not in response to Cochliobolus carbonum infection, indicating that PAD4 has a regulatory function [21].
• In no case are the TRP3 and TRP1 genes fused as has been found in other ascomycetes [22].
• HC toxin, the host-selective toxin of the maize pathogen Cochliobolus carbonum, inhibited maize histone deacetylase (HD) at 2 microM [16].
• In particular, sexual and asexual sporulation both require Chk1 function in Cochliobolus heterostrophus, in contrast to Pmk1, but perhaps more similar to yeast, where Fus3 transmits the mating signal [8].
• Because RPB2 is a single-copy gene of large size with a modest rate of evolutionary change, it provides good phylogenetic resolution of Ascomycota [23].

Analytical, diagnostic and therapeutic context of Ascomycota

• Studies of Cochliobolus lunatus m118 steroid metabolism by thin-layer chromatography, mass spectrometry and NMR spectroscopy revealed that the fungus hydroxylates progesterone at positions 7 alpha, 11 beta and 14 alpha, and oxidizes the 11 beta-hydroxy group to the ketone [24].
• Oral administration of SSG, a beta-glucan obtained from Sclerotinia sclerotiorum, affects the function of Peyer's patch cells [25].
• Northern blot and suppression subtractive hybridization analyses showed that presence of a low amount of quinate, inducer of the quinate pathway, resulted in increased levels of arom mRNA, consistent with the compensation effect observed in ascomycetes [26].
• Sequence analysis revealed a high degree of similarity between the deduced amino-acid sequences in the C-terminal catalytic domains of all known HMG-CoA reductases, but the highest degree was found between the sequences of both analysed ascomycetes [27].
• Crystallization, X-ray diffraction analysis and phasing of 17beta-hydroxysteroid dehydrogenase from the fungus Cochliobolus lunatus [28].

References