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Characterization of fungal soil communities by F-RISA and arbuscular mycorrhizal fungi from Araucaria angustifolia forest soils after replanting and wildfire disturbances

PATREZE, C. M.; PAULO, E. N. De; MARTINELLI, A. P.; CARDOSO, E. J. B.; TSAI, S. M.
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.04%
The Fungal Ribosomal Intergenic Spacer Analysis (F-RISA) was used to characterize soil fungal communities from three ecosystems of Araucaria angustifolia from Brazil: a native forest and two replanted forest ecosystems, one of them with a past history of wildfire. The arbuscular mycorrhizal fungi (AMF) infection was evaluated in Araucaria roots of 18-month-old axenic plants previously inoculated with soils collected from those areas in a greenhouse experiment. The principal component analysis of F-RISA profiles showed different soil fungal community between the three studied areas. Sixty three percent of F-RISA fragments amplified in the soil and the substrate samples presented lengths between 500 and 700 bp. The number of Operational Taxonomic Units (OTUs) was 34 for soil and 38 for substrate, however, more fragments were detected in soil (214) than in substrate (163). An in silico F-RISA analysis to compare our data with ITS1-5.8S-ITS2 sequences from NCBI database showed the presence of Ascomycota, Basidiomycota and Glomeromycota among the soil and substrate fungal communities. AMF infection was higher in plants inoculated with soil from the native forest and the replanted forest with wildfire, both presenting similar chemical characteristics but with different disturbance levels. These results indicate that soil chemical composition may influence the soil fungal community structures rather than the anthropogenic or fire disturbances.

Identification of genes and proteins involved in the regulation of orchid mycorrhiza; Identificação de genes e proteínas envolvidos na regulação de micorrizas de orquídeas

Valadares, Rafael Borges da Silva
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 14/02/2014 EN
Relevância na Pesquisa
36.2%
Orchids are characterized by producing minute endosperm-lacking seeds, which depend on mycorrhizal fungi for germination and embryo development. Some aclorophyllous orchids remain dependent on the mycorrhizal association for carbon acquisition during their whole life history, whereasother orchids develop photosynthesis. Despite the biological significance of orchid mycorrhiza, gene expression studies are lacking. We have used different highthroughput approaches in order to understanding the mechanisms regulating orchid mycorrhiza development and functioning. Firstly, we have used a 2D-LC-MS/MS approach coupled to isobaric tagging for relative and absolute quantification (iTRAQ) to identify proteins with differential accumulation in Oncidium sphacelatum at different stages of mycorrhizal protocorm development (achlorophyllous and green protocorms) after seed inoculation with a Ceratobasidium sp. isolate. Quantitative analysis showed that the expected changes in carbon metabolism in green protocorms were accompanied by enhanced accumulation of proteins involved in the modulation of reactive oxygen species homeostasis, defense related responses, phytoalexins and carotenoid biosynthesis, suggesting that orchid protocorms undergo profound metabolic changes during the switch from the fully mycoheterotrophic to the photosynthethic stage. Secondly...

Análise, via RNAseq, do transcritoma da cana-de-açúcar e identificação de genes expressos em resposta a Sporisorium scitamineum, o agente causal do carvão; RNAseq based transcriptome analysis and identification of sugarcane genes expressed in response to Sporisorium scitamineum, the causal agent of smut

Palhares, Alessandra Carolina
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 09/09/2014 PT
Relevância na Pesquisa
36.2%
A cana-de-açúcar (Saccharum spp.) é uma importante cultura agrícola, sendo hospedeira de vários patógenos, incluindo o fungo biotrófico Sporisorium scitamineum, agente causal do carvão. A doença reduz a produtividade das lavouras de cana e a qualidade de seus produtos, sendo reconhecida pelo desenvolvimento de uma estrutura em forma de chicote, onde os teliósporos são produzidos. O objetivo deste estudo foi analisar o transcritoma da interação cana-de-açúcar - S. scitamineum, visando a identificação de genes do hospedeiro diferencialmente expressos em resposta à infecção fúngica. Gemas da variedade tolerante 'RB92-5345' foram inoculadas com S. scitamineum e mantidas em casa de vegetação para a coleta das amostras, em dois momentos: 120 h após a inoculação, e no momento da emissão do chicote, aos 200 dias após a inoculação. Foram construídas 12 bibliotecas com base na abordagem RNAseq. Três estratégias computacionais foram utilizadas nas etapas de mapeamento e análise da expressão diferencial de genes da cana: (i) STAR e DESeq, tomando como referência o genoma do sorgo; (ii) Bowtie 2 e DESeq, e (iii) CLC Genomics Workbench, tomando como referência as sequências codificadoras (CDS) do sorgo. Diagramas de Venn foram construídos para identificar genes diferencialmente expressos comuns às três estratégias computacionais...

COX24 codes for a mitochondrial protein required for processing of the COX1 transcript

Barros, Mario H.; Myers, Alan M.; Van Driesche, Sarah; Tzagoloff, Alexander
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 3743-3751
ENG
Relevância na Pesquisa
36.15%
In most strains of Saccharomyces cerevisiae the mitochondrial gene COX1, for subunit 1 of cytochrome oxidase, contains multiple exons and introns. Processing of COX1 primary transcript requires accessory proteins factors, some of which are encoded by nuclear genes and others by reading frames residing in some of the introns of the COX1 and COB genes. Here we show that the low molecular weight protein product of open reading frame YLR204W, for which we propose the name COX24, is also involved in processing of COX1 RNA intermediates. The growth defect of cox24 mutants is partially rescued in strains harboring mitochondrial DNA lacking introns. Northern blot analyses of mitochondrial transcripts indicate cox24 null mutants to be blocked in processing of introns aI2 and aI3. The dependence of intron aI3 excision on Cox24p is also supported by the growth properties of the cox24 mutant harboring mitochondrial DNA with different intron compositions. The intermediate phenotype of the cox24 mutant in the background of intronless mitochondrial DNA, however, suggests that in addition to its role in splicing of the COX1 pre-mRNA, Cox24p still has another function. Based on the analysis of a cox14-cox24 double mutant, we propose that the other function of Cox24p is related to translation of the COX1 mRNA. © 2006 by The American Society for Biochemistry and Molecular Biology...

Identificação e caracterização de genes potencialmente transferidos horizontalmente no genoma do fitopatogeno C. perniciosa, causador da doença ?vassoura de bruxa? no cacaueiro

Jose Pedro Fonseca
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 07/03/2005 PT
Relevância na Pesquisa
36.29%
Transferência horizontal de genes (HGT) pode ser definida como a transmissão de genes entre diferentes grupos taxonômicos no qual o gene incorporado ao genoma do organismo receptor pode ser mantido ao longo de sucessivas gerações pelo sistema reprodutivo tradicional do receptor. HGT é reconhecida como uma das principais forças atuantes na evolução de genomas de procariotos, que têm significantes percentagens adquiridas por esse processo (1.5% a 14.5%).Em eucariotos, entretanto, o papel de HGT começou apenas recentemente a ser avaliado e geralmente é relacionado com algum cenário evolutivo específico como, por exemplo, a relação hospedeiro-patógeno. Espécies de fungos são consideradas especialmente suscetíveis a HGT por seu modo íntimo de associação com hospedeiros. Em vista disso, no presente projeto foi elaborado um protocolo para identificação de potenciais candidatos a HGT no genoma de Crinipellis perniciosa, o fungo causador da vassoura de bruxa nos cacauais. Primeiramente foi criado um banco de dados contendo todas as seqüências putativas de proteínas (ORFs) de fungos disponíveis no banco de dados do NCBI nr (03/2004). Uma montagem-rascunho de seqüências genômicas ?shotgun? de C. perniciosa, num total de 17.000 contigs...

Effect of azoles in Candida glabrata biofilms and its relation with ERG genes expression

Rodrigues, Célia; Silva, Sónia Carina; Azeredo, Joana; Gonçalves, Bruna; Henriques, Mariana
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em /06/2013 ENG
Relevância na Pesquisa
36.05%
The occurrence of fungal infections has been significantly increasing, thus contributing to higher morbidity and mortality. The use of broad-spectrum antibiotics, catheters, immunosuppression diseases, chemo and radiotherapy are predisposing factors for invasive fungal infection development. Candida albicans is the predominant species in both health and disease conditions, yet, in the last two decades the number of infections due to non-Candida albicans Candida species has increased significantly. Once believed as non-pathogenic, Candida glabrata rapidly was perceived to be responsible for many human diseases. Despite lacking a number of virulence factors allied to the majority of Candida pathogenicity, C. glabrata possesses high ability to colonize medical devices and human epithelium, resulting generally in biofilms formation ability. Its intrinsically low susceptibility to azoles, such as triazoles (e.g. fluconazole (Flu), voriconazole (Vcz)) and its biofilms tolerance is another problem. The aim of this study was to evaluate the effects of Flu (largely used) and Vcz (hospitalenvironment exclusive) in the control of C. glabrata biofilms and its relation with the expression of genes encoding for Ergosterol: ERG3, ERG6 and ERG11. Three isolates of C. glabrata (vaginal...

Sequencing of a 17.6 kb segment on the right arm of yeast chromosome VII reveals 12 ORFs, including CCT, ADE3 and TR-I genes, homologues of the yeast PMT and EF1G genes, of the human and bacterial electron-transferring flavoproteins (beta-chain) and of the Escherichia coli phosphoserine phosphohydrolase, and five new ORFs.

Guerreiro, Paulo; Barreiros, Tânia; Soares, Helena; Cyrne, Luísa; Maia e Silva, Alexandra; Rodrigues-Pousada, Claudina
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em /03/1996 ENG
Relevância na Pesquisa
46.07%
A 17.6 kb DNA fragment from the right arm of chromosome VII of Saccharomyces cerevisiae has been sequenced and analysed. The sequence contains twelve open reading frames (ORFs) longer than 100 amino acids. Three genes had already been cloned and sequenced: CCT, ADE3 and TR-I. Two ORFs are similar to other yeast genes: G7722 with the YAL023 (PMT2) and PMT1 genes, encoding two integral membrane proteins, and G7727 with the first half of the genes encoding elongation factors 1gamma, TEF3 and TEF4. Two other ORFs, G7742 and G7744, are most probably yeast orthologues of the human and Paracoccus denitrificans electron-transferring flavoproteins (beta chain) and of the Escherichia coli phosphoserine phosphohydrolase. The five remaining identified ORFs do not show detectable homology with other protein sequences deposited in data banks. The sequence has been deposited in the EMBL data library under Accession Number Z49133.

Electrotransformation and Expression of Bacterial Genes Encoding Hygromycin Phosphotransferase and β-Galactosidase in the Pathogenic Fungus Histoplasma capsulatum

Woods, Jon P.; Heinecke, Elizabeth L.; Goldman, William E.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /04/1998 EN
Relevância na Pesquisa
36.07%
We developed an efficient electrotransformation system for the pathogenic fungus Histoplasma capsulatum and used it to examine the effects of features of the transforming DNA on transformation efficiency and fate of the transforming DNA and to demonstrate fungal expression of two recombinant Escherichia coli genes, hph and lacZ. Linearized DNA and plasmids containing Histoplasma telomeric sequences showed the greatest transformation efficiencies, while the plasmid vector had no significant effect, nor did the derivation of the selectable URA5 marker (native Histoplasma gene or a heterologous Podospora anserina gene). Electrotransformation resulted in more frequent multimerization, other modification, or possibly chromosomal integration of transforming telomeric plasmids when saturating amounts of DNA were used, but this effect was not observed with smaller amounts of transforming DNA. We developed another selection system using a hygromycin B resistance marker from plasmid pAN7-1, consisting of the E. coli hph gene flanked by Aspergillus nidulans promoter and terminator sequences. Much of the heterologous fungal sequences could be removed without compromising function in H. capsulatum, allowing construction of a substantially smaller effective marker fragment. Transformation efficiency increased when nonselective conditions were maintained for a time after electrotransformation before selection with the protein synthesis inhibitor hygromycin B was imposed. Finally...

Differential expression of Glomus intraradices genes in external mycelium and mycorrhizal roots of tomato and barley

Delp, G.; Timonen, S.; Rosewarne, G.; Barker, S.; Smith, S.
Fonte: Cambridge Univ Press Publicador: Cambridge Univ Press
Tipo: Artigo de Revista Científica
Publicado em //2003 EN
Relevância na Pesquisa
46.36%
Relative quantitative RT-PCR and western blotting were used to investigate the expression of three genes with potentially regulatory functions from the arbuscular mycorrhizal fungus Glomus intraradices in symbiosis with tomato and barley. Standardisation of total RNA per sample and determination of different ratios of plant and fungal RNA in roots as colonisation proceeded were achieved by relative quantitative RT-PCR using universal (NS1/NS21) and organism-specific rRNA primers. In addition, generic primers were designed for amplification of plant or fungal β-tubulin genes and for plant glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes as these have been suggested as useful controls in symbiotic systems. The fungal genes Ginmyc1 and Ginhb1 were expressed only in the external mycelium and not in colonised roots at both mRNA and protein levels, with the proteins detected almost exclusively in the insoluble fractions. In contrast, mRNA of Ginmyc2 was identified in both external and intraradical mycelium. In mycorrhizal roots, Ginmyc2 and fungal β-tubulin mRNAs increased in proportion to fungal rRNA as colonisation proceeded, suggesting that accumulation reflected intraradical fungal growth. Fungal α-tubulin protein and β-tubulin mRNA both appeared to be more abundantly accumulated in AM hyphae within heavily colonised roots than in external hyphae...

The effects of stubble retention and nitrogen application on soil microbial community structure and functional gene abundance under irrigated maize

Wakelin, S.; Colloff, M.; Harvey, P.; Marschner, P.; Gregg, A.; Rogers, S.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2007 EN
Relevância na Pesquisa
36.07%
The effects of agronomic management practices on the soil microbial community were investigated in a maize production system in New South Wales, Australia. The site has been intensively studied to measure the impact of stubble management and N-fertilizer application on greenhouse gas emissions (CO₂ and N₂O), N-cycling, pathology, soil structure and yield. As all of these endpoints can be regulated by microbial processes, the microbiology of the system was examined. Soil samples were taken after a winter fallow period and the diversity of the bacterial and fungal communities was measured using PCR-denaturing gradient gel electrophoresis. Stubble and N shifted the structure of bacterial and fungal communities with the primary driver being stubble addition on the fungal community structure (P<0.05 for all effects). Changes in C, N (total and NO3), K and Na, were correlated (P<0.05) with variation in the microbial community structure. Quantitative PCR showed that nifH (nitrogen fixation) and napA (denitrification) gene abundance increased upon stubble retention, whereas amoA gene numbers were increased by N addition. These results showed that the management of both stubble and N have significant and long-term impacts on the size and structure of the soil microbial community at phylogenetic and functional levels.; Steven A. Wakelin...

Carbon catabolite repression in plant pathogenic fungi: isolation and characterization of the Gibberella fujikuroi and Botrytis cinerea creA genes

Tudzynski, B.; Liu, S.; Kelly, J.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2000 EN
Relevância na Pesquisa
36.07%
The creA genes of two plant pathogenic fungi, the gibberellin-producing rice pathogen Gibberella fujikuroi and the gray mold Botrytis cinerea, were isolated and characterized. The deduced amino acid sequences of both glucose repressors are 64% identical to each other and 59% (G. fujikuroi) and 61% (B. cinerea) identical to the CreA protein of Aspergillus nidulans. The zinc finger regions of the Gibberella and Botrytis CreA proteins shared 98% identity with the corresponding zinc finger region of the A. nidulans protein, and studies by complementation of a creA null mutant of A. nidulans showed that the proteins are functional homologues of A. nidulans CreA. Northern blot analysis revealed that creA transcript levels are independent of the carbon source in both fungi.; Tudzynski, Bettina ; Liu, Songjie ; Kelly, Joan M.

Comparative study of genes expressed from rice fungus-resistant and susceptible lines during interactions with Magnaporthe oryzae

Shi, B.J.; Wang, G.L.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
Relevância na Pesquisa
36.02%
Rice blast disease caused by Magnaporthe oryzae is the most important fungal disease of rice. To understand the molecular basis of interaction between the fungus and rice, we constructed a cDNA library from a rice-resistant line inoculated with M. oryzae. One hundred and fifty-three cDNA clones were sequence analyzed, of which 129 exhibited significant nucleotide sequence homology to known genes, 21 were homologous to unknown genes, while three clones did not match to any database. However, these three unmatched clones showed sequence homology at protein level in the protein databases and one of them encoded a disease resistance-related protein kinase and was abundant in the EST collection. Northern analysis showed that this disease resistance-related protein kinase gene was induced by inoculation and only expressed in the rice-resistant, but not susceptible, lines. Southern analysis showed that this gene was present in a single copy in the rice genome and co-segregated with the M. oryzae resistance in the cross of the resistant and susceptible lines. This study illustrates that sequencing of ESTs from inoculated resistant plants can reveal genes responsive to pathogen infection, which could help understand plant defense mechanisms.; http://www.elsevier.com/wps/find/journaldescription.cws_home/506033/description#description; Bu-Jun Shi and Guo-Liang Wang; Copyright © 2008 Elsevier B.V. All rights reserved.

Mutations in genes encoding sorting nexins alter production of intracellular and extracellular proteases in Aspergillus nidulans

Katz, M.; Evans, C.; Heagney, E.; vanKuyk, P.; Kelly, J.; Cheetham, B.
Fonte: Genetics Publicador: Genetics
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
46.1%
XprG, a putative p53-like transcriptional activator, regulates production of extracellular proteases in response to nutrient limitation and may also have a role in programmed cell death. To identify genes that may be involved in the XprG regulatory pathway, xprG2 revertants were isolated and shown to carry mutations in genes which we have named sogA-C (suppressors of xprG). The translocation breakpoint in the sogA1 mutant was localized to a homolog of Saccharomyces cerevisiae VPS5 and mapping data indicated that sogB was tightly linked to a VPS17 homolog. Complementation of the sogA1 and sogB1 mutations and identification of nonsense mutations in the sogA2 and sogB1 alleles confirmed the identification. Vps17p and Vps5p are part of a complex involved in sorting of vacuolar proteins in yeast and regulation of cell-surface receptors in mammals. Protease zymograms indicate that mutations in sogA-C permit secretion of intracellular proteases, as in S. cerevisiae vps5 and vps17 mutants. In contrast to S. cerevisiae, the production of intracellular protease was much higher in the mutants. Analysis of serine protease gene expression suggests that an XprG-independent mechanism for regulation of extracellular protease gene expression in response to carbon starvation exists and is activated in the pseudorevertants.; Margaret E. Katz...

Tagging pathogenicity genes in the interaction of barley and the fungal pathogen, Rhynchosporium secalis.

Yuill, Shae Brian
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2008
Relevância na Pesquisa
36.29%
The purpose of this study was to identify pathogenicity genes in the fungal pathogen of cultivated barley, Rhynchosporium secalis. Pathogenicity genes are described as genes that are critical for the successful invasion and colonisation of the host plant but not necessary for life cycle completion in culture. To identify genes a pool of insertion mutants was generated. Insertional mutants were generated by two methods, restriction enzyme-mediated integration (REMI) and Agrobacterium tumefaciens-mediated transformation (ATMT). A detailed REMI study showed circular pAN7-1 vector produced higher transformation efficiencies than linear vector at all enzyme levels tested. Fungal strain 5, in combination with 20 units of the restriction enzyme BamHI produced the highest observed transformation efficiency with approximately 40% of these mutants producing simple, single integrations based on interpreted Southern data. The addition of BamHI increased transformation efficiency at all enzyme levels tested with the exception of the highest enzyme concentration: 200 units of enzyme/transformation reaction. In comparison to REMI, the ATMT protocol proved more efficient than REMI and the binary vector backbone pPZP200 produced >50% simple single copy integrations...

Comparative pathogenomics reveals horizontally acquired novel virulence genes in fungi infecting cereal hosts

Gardiner, Donald M.; McDonald, Megan C.; Covarelli, Lorenzo; Solomon, Peter S.; Rusu, Anca G.; Marshall, Mhairi; Kazan, Kemal; Chakraborty, Sukumar; McDonald, Bruce A.; Manners, John M.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica Formato: 22 pages
Relevância na Pesquisa
36.25%
Comparative analyses of pathogen genomes provide new insights into how pathogens have evolved common and divergent virulence strategies to invade related plant species. Fusarium crown and root rots are important diseases of wheat and barley world-wide. In Australia, these diseases are primarily caused by the fungal pathogen Fusarium pseudograminearum. Comparative genomic analyses showed that the F. pseudograminearum genome encodes proteins that are present in other fungal pathogens of cereals but absent in non-cereal pathogens. In some cases, these cereal pathogen specific genes were also found in bacteria associated with plants. Phylogenetic analysis of selected F. pseudograminearum genes supported the hypothesis of horizontal gene transfer into diverse cereal pathogens. Two horizontally acquired genes with no previously known role in fungal pathogenesis were studied functionally via gene knockout methods and shown to significantly affect virulence of F. pseudograminearum on the cereal hosts wheat and barley. Our results indicate using comparative genomics to identify genes specific to pathogens of related hosts reveals novel virulence genes and illustrates the importance of horizontal gene transfer in the evolution of plant infecting fungal pathogens.; DMG was supported by an Australian Research Council Post Doctoral Fellowship (www.arc.gov.au). The CSIRO Transformational Biology Capability Platform (www.csiro.au) supported the genome sequencing work presented in this manuscript. LC was supported by an Australian Government Endeavour foundation award (www.deewr.gov.au/International/EndeavourAwards/Pages/Home.aspx). MCM was supported by the ETH Zurich (www.ethz.ch).

Diversity of immunoglobulin E-encoding transcripts in sinus mucosa of subjects diagnosed with non-allergic fungal eosinophilic sinusitis

Levin, M.; Tan, L.W.; Baker, L.; Wormald, P.J.; Greiff, L.; Ohlin, M.
Fonte: Blackwell Science Ltd Publicador: Blackwell Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
Relevância na Pesquisa
36.07%
Background: The role of allergy in the aetiopathogenesis of chronic rhinosinusitis (CRS) remains controversial. For example, in some cases with sinus fungal infections allergy can be demonstrated by standard tests. In other cases, such signs can be absent despite elevated levels of IgE-positive cells in sinus tissue and the presence of IgE and eosinophils in the sinus mucous. Objective: To define the nature of molecular diversity in antibodies of the IgE isotype at the site of local inflammation in subjects diagnosed with non-allergic fungal eosinophilic sinusitis (NAFES). Methods: The local occurrence and sequence characteristics of IgE-encoding transcripts in NAFES patients were investigated and compared with sequences found in subjects diagnosed with CRS featuring systemic allergy. These sequences have also been compared with other reported IgE-encoding transcriptomes. Results: IGHV genes derived from major subgroups 1, 3, 4 and 5 and a diverse set of IGHD and IGHJ genes were shown to create the IgE repertoire in patients diagnosed with NAFES and CRS. The average lengths of the third hypervariable loop in these populations were 15.8 and 14.6 residues. The sequences showed evidence of extensive somatic hypermutation (mutation frequency: NAFES...

Comparative Genome Analysis of Trichophyton rubrum and Related Dermatophytes Reveals Candidate Genes Involved in Infection

Martinez, Diego A.; Oliver, Brian G.; Graeser, Yvonne; Goldberg, Jonathan M.; Li, Wenjun; Martinez-Rossi, Nilce M.; Monod, Michel; Shelest, Ekaterina; Barton, Richard C.; Birch, Elizabeth; Brakhage, Axel A.; Chen, Zehua; Gurr, Sarah J.; Heiman, David; Hei
Fonte: AMER SOC MICROBIOLOGY; WASHINGTON Publicador: AMER SOC MICROBIOLOGY; WASHINGTON
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.12%
The major cause of athlete's foot is Trichophyton rubrum, a dermatophyte or fungal pathogen of human skin. To facilitate molecular analyses of the dermatophytes, we sequenced T. rubrum and four related species, Trichophyton tonsurans, Trichophyton equinum, Microsporum canis, and Microsporum gypseum. These species differ in host range, mating, and disease progression. The dermatophyte genomes are highly colinear yet contain gene family expansions not found in other human-associated fungi. Dermatophyte genomes are enriched for gene families containing the LysM domain, which binds chitin and potentially related carbohydrates. These LysM domains differ in sequence from those in other species in regions of the peptide that could affect substrate binding. The dermatophytes also encode novel sets of fungus-specific kinases with unknown specificity, including nonfunctional pseudokinases, which may inhibit phosphorylation by competing for kinase sites within substrates, acting as allosteric effectors, or acting as scaffolds for signaling. The dermatophytes are also enriched for a large number of enzymes that synthesize secondary metabolites, including dermatophyte-specific genes that could synthesize novel compounds. Finally, dermatophytes are enriched in several classes of proteases that are necessary for fungal growth and nutrient acquisition on keratinized tissues. Despite differences in mating ability...

Comparative Pathogenomics Reveals Horizontally Acquired Novel Virulence Genes in Fungi Infecting Cereal Hosts

Gardiner, Donald M.; McDonald, Megan C.; Covarelli, Lorenzo; Solomon, Peter S.; Rusu, Anca G.; Marshall, Mhairi; Kazan, Kemal; Chakraborty, Sukumar; McDonald, Bruce A.; Manners, John M.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
36.25%
Comparative analyses of pathogen genomes provide new insights into how pathogens have evolved common and divergent virulence strategies to invade related plant species. Fusarium crown and root rots are important diseases of wheat and barley world-wide. In Australia, these diseases are primarily caused by the fungal pathogen Fusarium pseudograminearum. Comparative genomic analyses showed that the F. pseudograminearum genome encodes proteins that are present in other fungal pathogens of cereals but absent in non-cereal pathogens. In some cases, these cereal pathogen specific genes were also found in bacteria associated with plants. Phylogenetic analysis of selected F. pseudograminearum genes supported the hypothesis of horizontal gene transfer into diverse cereal pathogens. Two horizontally acquired genes with no previously known role in fungal pathogenesis were studied functionally via gene knockout methods and shown to significantly affect virulence of F. pseudograminearum on the cereal hosts wheat and barley. Our results indicate using comparative genomics to identify genes specific to pathogens of related hosts reveals novel virulence genes and illustrates the importance of horizontal gene transfer in the evolution of plant infecting fungal pathogens.; DMG was supported by an Australian Research Council Post Doctoral Fellowship (www.arc.gov.au). The CSIRO Transformational Biology Capability Platform (www.csiro.au) supported the genome sequencing work presented in this manuscript. LC was supported by an Australian Government Endeavour foundation award (www.deewr.gov.au/International/EndeavourAwards/Pages/Home.aspx). MCM was supported by the ETH Zurich (www.ethz.ch). The funders had no role in study design...

Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae

Walker, M.E.; Nguyen, T.D.; Liccioli, T.; Schmid, F.; Kalatzis, N.; Sundstrom, J.F.; Gardner, J.M.; Jiranek, V.
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
Relevância na Pesquisa
45.92%
BACKGROUND: Wine fermentation is a harsh ecological niche to which wine yeast are well adapted. The initial high osmotic pressure and acidity of grape juice is followed by nutrient depletion and increasing concentrations of ethanol as the fermentation progresses. Yeast's adaptation to these and many other environmental stresses, enables successful completion of high-sugar fermentations. Earlier transcriptomic and growth studies have tentatively identified genes important for high-sugar fermentation. Whilst useful, such studies did not consider extended growth (>5 days) in a temporally dynamic multi-stressor environment such as that found in many industrial fermentation processes. Here, we identify genes whose deletion has minimal or no effect on growth, but results in failure to achieve timely completion of the fermentation of a chemically defined grape juice with 200 g L-1 total sugar. RESULTS: Micro- and laboratory-scale experimental fermentations were conducted to identify 72 clones from ~5,100 homozygous diploid single-gene yeast deletants, which exhibited protracted fermentation in a high-sugar medium. Another 21 clones (related by gene function, but initially eliminated from the screen because of possible growth defects) were also included. Clustering and numerical enrichment of genes annotated to specific Gene Ontology (GO) terms highlighted the vacuole's role in ion homeostasis and pH regulation...

Pest and disease protection conferred by expression of barley �-hordothionin and Nicotiana alata proteinase inhibitor genes in transgenic tobacco

Charity, Julia; Hughes, Peter; Anderson, Marilyn; Bittisnich, D; Whitecross, Malcolm; Higgins, T J V
Fonte: CSIRO Publishing Publicador: CSIRO Publishing
Tipo: Artigo de Revista Científica
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Proteinase inhibitors and thionins are among the many proteins thought to have a role in plant defence against pests and pathogens. Complementary DNA clones encoding the precursors of a multi-domain proteinase inhibitor from Nicotiana alata Link et Otto (NA-PI) (Mr approximately 43 000) and a β-hordothionin (β-HTH) (Mr approximately 13 000) from barley, were linked to constitutive promoters and subsequently transferred by Agrobacterium-mediated transformation into tobacco. The NA-PI and β-HTH precursor proteins were synthesised and post-translationally processed in transgenic tobacco and accumulated as polypeptides of apparent size Mr approximately 6000 and Mr approximately 8500, respectively. The na-pi and β-hth genes were stably inherited for at least two generations. Transgenic tobacco plants containing the highest amounts of NA-PI and β-HTH were crossed to produce plants containing both genes. Helicoverpa armigera (tobacco budworm) larvae that ingested transgenic tobacco leaves expressing both NA-PI and β-HTH, exhibited higher mortality and slower development relative to larvae fed on non-transgenic tobacco. NA-PI and β-HTH, either alone, or in combination, also conferred protection against the fungal pathogen, Botrytis cinerea (grey mould) and the bacterial pathogen...