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Jeffrey A Rollins - One of the best experts on this subject based on the ideXlab platform.
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the gata type ivb zinc finger transcription factor ssnsd1 regulates asexual sexual development and appressoria formation in sclerotinia sclerotiorum
Molecular Plant Pathology, 2018Co-Authors: Selvakumar Veluchamy, Yanzhi Liu, Yanhua Zhang, Hongyu Pan, Jeffrey A RollinsAbstract:The sclerotium, a multicellular structure composed of the compact aggregation of vegetative hyphae, is critical for the long-term survival and sexual reproduction of the plant-pathogenic fungus Sclerotinia sclerotiorum. The development and carpogenic germination of sclerotia are regulated by integrating signals from both environmental and endogenous processes. Here, we report the regulatory functions of the S. sclerotiorum GATA-type IVb zinc-finger transcription factor SsNsd1 in these processes. SsNsd1 is orthologous to the Aspergillus nidulans NsdD (never in sexual development) and the Neurospora crassa SUB-1 (submerged protoperithecia-1) proteins. Ssnsd1 gene transcript accumulation remains relatively low, but variable, during vegetative mycelial growth and multicellular development. Ssnsd1 deletion mutants (Δnsd1-KOs) produce phialides and phialospores (spermatia) excessively in vegetative hyphae and promiscuously within the interior medulla of sclerotia. In contrast, phialospore development occurs only on the sclerotium surface in the wild-type. Loss of SsNsd1 function affects sclerotium structural integrity and disrupts ascogonia formation during conditioning for carpogenic germination. As a consequence, Apothecium development is abolished. The Ssnsd1 deletion mutants are also defective in the transition from hyphae to compound appressorium formation, resulting in a loss of pathogenicity on unwounded hosts. In sum, our results demonstrate that SsNsd1 functions in a regulatory role similar to its ascomycete orthologues in regulating sexual and asexual development. Further, SsNsd1 appears to have evolved as a regulator of pre-penetration infectious development required for the successful infection of its many hosts.
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characterization of mat gene functions in the life cycle of sclerotinia sclerotiorum reveals a lineage specific mat gene functioning in Apothecium morphogenesis
Fungal Biology, 2016Co-Authors: Benjamin Doughan, Jeffrey A RollinsAbstract:Sclerotinia sclerotiorum (Lib.) de Bary is a phytopathogenic fungus that relies on the completion of the sexual cycle to initiate aerial infections. The sexual cycle produces apothecia required for inoculum dispersal. In this study, insight into the regulation of apothecial multicellular development was pursued through functional characterization of mating-type genes. These genes are hypothesized to encode master regulatory proteins required for aspects of sexual development ranging from fertilization through fertile fruiting body development. Experimentally, loss-of-function mutants were created for the conserved core mating-type genes (MAT1-1-1, and MAT1-2-1), and the lineage-specific genes found only in S. sclerotiorum and closely related fungi (MAT1-1-5, and MAT1-2-4). The MAT1-1-1, MAT1-1-5, and MAT1-2-1 mutants are able to form ascogonia but are blocked in all aspects of Apothecium development. These mutants also exhibit defects in secondary sexual characters including lower numbers of spermatia. The MAT1-2-4 mutants are delayed in carpogenic germination accompanied with altered disc morphogenesis and ascospore production. They too produce lower numbers of spermatia. All four MAT gene mutants showed alterations in the expression of putative pheromone precursor (Ppg-1) and pheromone receptor (PreA, PreB) genes. Our findings support the involvement of MAT genes in sexual fertility, gene regulation, meiosis, and morphogenesis in S. sclerotiorum.
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sclerotinia sclerotiorum γ glutamyl transpeptidase ss ggt1 is required for regulating glutathione accumulation and development of sclerotia and compound appressoria
Molecular Plant-microbe Interactions, 2012Co-Authors: Xiaofei Liang, Jeffrey A RollinsAbstract:Transcripts encoding Sclerotinia sclerotiorum γ-glutamyl transpeptidase (Ss-Ggt1) were found to accumulate specifically during sclerotium, Apothecium, and compound appressorium development in S. sclerotiorum. To determine the requirement of this protein in these developmental processes, gene deletion mutants of Ss-ggt1 were generated and five independent homokaryotic ΔSs-ggt1 mutants were characterized. All deletion mutants overproduced sclerotial initials that were arrested in further development or eventually produced sclerotia with aberrant rind layers. During incubation for carpogenic germination, these sclerotia decayed and failed to produce apothecia. Total glutathione accumulation was approximately 10-fold higher and H2O2 hyperaccumulated in ΔSs-ggt1 sclerotia compared with the wild type. Production of compound appressoria was also negatively affected. On host plants, these mutants exhibited a defect in infection efficiency and a delay in initial symptom development unless the host tissue was wound...
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the development specific protein ssp1 from sclerotinia sclerotiorum is encoded by a novel gene expressed exclusively in sclerotium tissues
Mycologia, 2009Co-Authors: Jeffrey A RollinsAbstract:The gene encoding a development-specific protein (Ssp1) was identified; it previously was described as the major protein present in mature sclerotia of Sclerotinia sclerotiorum. To determine the developmental specificity of ssp1 gene expression in relation to protein accumulation we examined transcript and protein accumulation during various growth and development stages of the lifecycle. We found that ssp1 transcript accumulated exclusively within developing sclerotium tissue and not in any other examined stage of growth or development. In contrast high levels of Sspl protein were detectable by western blot and tandem mass spectrometry analyses in all stages of sclerotium as well as Apothecium development. Immunolocalization further indicated that Ssp1 protein bodies were depleted from the sclerotium tissue surrounding the site of Apothecium germination, but by this method Sspl was not detected in the Apothecium. Together these findings suggest that Sspl is not metabolized during carpogenic germination, instead it is translocated from the sclerotium to the Apothecium in an antigenically novel form. Outside the Sclerotiniaceae ssp1 homologs were found only from the sclerotium-forming Aspergillus species A. flavus and A. oryzae. Further studies concerning the regulation and function of this gene and its occurrence in other species have the potential to inform our understanding of sclerotium development and the evolution of sclerotia and other forms of fungal stroma.
Troian, Rogério Fraga - One of the best experts on this subject based on the ideXlab platform.
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Análise do secretoma da interação entre Trichoderma Harzianum e os estagios de desenvolvimento do fitopátogeno Sclerotinia Sclerotiorum
2015Co-Authors: Troian, Rogério FragaAbstract:Trichoderma harzianum tem recebido considerável atenção como potencial agente de controle biológico, agindo como um micoparasita contra diversos fitopatógenos habitantes do solo, incluindo Sclerotinia sclerotiorum. O objetivo deste estudo foi vizualizar por microscopia eletrônica de varredura (MEV), a interação entre T. harzianum e S. sclerotiorum, assim como mapear e identificar as proteínas secretadas por T. harzianum quando cultivado na presença de parede celular, apotécio e escleródio de S. sclerotiorum. Nos testes de interação por MEV, T. harzianum provou ser um potente antagonista de S. sclerotiorum, mostrando que as hifas do antagonista penetraram nas estruturas do fitopatógeno. Posteriomente foram construídos os mapas bidimensionais permitindo a visualização das diferentes proteínas secretadas de T. harzianum quando cultivadas na presença de diferentes etapas da vida de S. sclerotiorum sendo que um total de 139 spots foram analisados, e destes foram identificados 63. Das proteínas identificadas no secretoma 5 são exclusivas quando cultivadas em meio contendo apotécio, 9 em meio contendo escleródio e 4 contendo parede celular sendo 11 proteínas expressas nas 3 condições. A expressão dos genes foi feita usando PCR em tempo real a partir de RNA total de T. harzianum quando cultivadas na presença das três fases do ciclo de vida S. sclerotiorum (micélio, escleródios e apotécio) confirmando as proteínas secretadas. Nossos resultados fornecem um passo para a compreensão do processo de micoparasitismo entre T. harzianum durante sua interação com S.sclerotiorum permitindo a identificação das diferentes proteínas secretadas quando cultivadas com as fases do ciclo de vida desse fitopatógeno. _____________________________________________________________________________________ ABSTRACTTrichoderma harzianum has received considerable attention as a potential biological control agent, acting as a mycoparasite against several soilborne plant pathogens including Sclerotinia sclerotiorum. The objective of this study was to visualize electron microscopy (SEM), the interaction between T. harzianum and S. sclerotiorum as well as map and identify the proteins secreted by T. harzianum when grown in the presence of cell wall, and sclerotia of Apothecium S. sclerotiorum. In MEV interaction tests, T. harzianum proved to be a potent antagonist of S. sclerotiorum, showing that antagonist hyphae penetrated pathogen structures. After dimensional maps were constructed allowing the visualization of the different secreted proteins from T. harzianum when cultured in the presence of different stages of the life of S. sclerotiorum with a total of 139 spots were analyzed and identified 63. Of these proteins identified in secretome 5 are unique when grown in medium containing Apothecium, 9 in medium containing sclerotia and 4 containing cell wall being 11 proteins expressed in the 3 conditions. Expression of the gene was done using real-time PCR from total RNA of T. harzianum when cultured in the presence of the three phases of the lifecycle S. sclerotiorum (mycelium and sclerotia Apothecium) confirming secreted proteins. Our results provide a step towards understanding the mycoparasitism process between T. harzianum during their interaction with S.sclerotiorum allowing the identification of various secreted proteins when grown with the phases of the life of this pathogen cycle
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Análise do secretoma da interação entre Trichoderma Harzianum e os estagios de desenvolvimento do fitopátogeno Sclerotinia Sclerotiorum
2014Co-Authors: Troian, Rogério FragaAbstract:Tese (doutorado)—Universidade de Brasília, Departamento de Biologia Celular, Programa de Pós-Graduação em Biologia Molecular, 2014.Trichoderma harzianum tem recebido considerável atenção como potencial agente de controle biológico, agindo como um micoparasita contra diversos fitopatógenos habitantes do solo, incluindo Sclerotinia sclerotiorum. O objetivo deste estudo foi vizualizar por microscopia eletrônica de varredura (MEV), a interação entre T. harzianum e S. sclerotiorum, assim como mapear e identificar as proteínas secretadas por T. harzianum quando cultivado na presença de parede celular, apotécio e escleródio de S. sclerotiorum. Nos testes de interação por MEV, T. harzianum provou ser um potente antagonista de S. sclerotiorum, mostrando que as hifas do antagonista penetraram nas estruturas do fitopatógeno. Posteriomente foram construídos os mapas bidimensionais permitindo a visualização das diferentes proteínas secretadas de T. harzianum quando cultivadas na presença de diferentes etapas da vida de S. sclerotiorum sendo que um total de 139 spots foram analisados, e destes foram identificados 63. Das proteínas identificadas no secretoma 5 são exclusivas quando cultivadas em meio contendo apotécio, 9 em meio contendo escleródio e 4 contendo parede celular sendo 11 proteínas expressas nas 3 condições. A expressão dos genes foi feita usando PCR em tempo real a partir de RNA total de T. harzianum quando cultivadas na presença das três fases do ciclo de vida S. sclerotiorum (micélio, escleródios e apotécio) confirmando as proteínas secretadas. Nossos resultados fornecem um passo para a compreensão do processo de micoparasitismo entre T. harzianum durante sua interação com S.sclerotiorum permitindo a identificação das diferentes proteínas secretadas quando cultivadas com as fases do ciclo de vida desse fitopatógeno. _____________________________________________________________________________________ ABSTRACTTrichoderma harzianum has received considerable attention as a potential biological control agent, acting as a mycoparasite against several soilborne plant pathogens including Sclerotinia sclerotiorum. The objective of this study was to visualize electron microscopy (SEM), the interaction between T. harzianum and S. sclerotiorum as well as map and identify the proteins secreted by T. harzianum when grown in the presence of cell wall, and sclerotia of Apothecium S. sclerotiorum. In MEV interaction tests, T. harzianum proved to be a potent antagonist of S. sclerotiorum, showing that antagonist hyphae penetrated pathogen structures. After dimensional maps were constructed allowing the visualization of the different secreted proteins from T. harzianum when cultured in the presence of different stages of the life of S. sclerotiorum with a total of 139 spots were analyzed and identified 63. Of these proteins identified in secretome 5 are unique when grown in medium containing Apothecium, 9 in medium containing sclerotia and 4 containing cell wall being 11 proteins expressed in the 3 conditions. Expression of the gene was done using real-time PCR from total RNA of T. harzianum when cultured in the presence of the three phases of the lifecycle S. sclerotiorum (mycelium and sclerotia Apothecium) confirming secreted proteins. Our results provide a step towards understanding the mycoparasitism process between T. harzianum during their interaction with S.sclerotiorum allowing the identification of various secreted proteins when grown with the phases of the life of this pathogen cycle
Frank Kauff - One of the best experts on this subject based on the ideXlab platform.
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The Ascomycota Tree of Life: A Phylum-wide Phylogeny Clarifies the Origin and Evolution of Fundamental Reproductive and Ecological Traits
Systematic biology, 2009Co-Authors: Conrad L. Schoch, Jolanta Miadlikowska, Valérie Hofstetter, Gi Ho Sung, Francesc López-giráldez, Jeffrey P. Townsend, Barbara Robbertse, P. Brandon Matheny, Frank KauffAbstract:We present a 6-gene, 420-species maximum-likelihood phylogeny of Ascomycota, the largest phylum of Fungi. This analysis is the most taxonomically complete to date with species sampled from all 15 currently circumscribed classes. A number of superclass-level nodes that have previously evaded resolution and were unnamed in classifications of the Fungi are resolved for the first time. Based on the 6-gene phylogeny we conducted a phylogenetic informativeness analysis of all 6 genes and a series of ancestral character state reconstructions that focused on morphology of sporocarps, ascus dehiscence, and evolution of nutritional modes and ecologies. A gene-by-gene assessment of phylogenetic informativeness yielded higher levels of informativeness for protein genes (RPB1, RPB2, and TEF1) as compared with the ribosomal genes, which have been the standard bearer in fungal systematics. Our reconstruction of sporocarp characters is consistent with 2 origins for multicellular sexual reproductive structures in Ascomycota, once in the common ancestor of Pezizomycotina and once in the common ancestor of Neolectomycetes. This first report of dual origins of ascomycete sporocarps highlights the complicated nature of assessing homology of morphological traits across Fungi. Furthermore, ancestral reconstruction supports an open sporocarp with an exposed hymenium (Apothecium) as the primitive morphology for Pezizomycotina with multiple derivations of the partially (perithecia) or completely enclosed (cleistothecia) sporocarps. Ascus dehiscence is most informative at the class level within Pezizomycotina with most superclass nodes reconstructed equivocally. Character-state reconstructions support a terrestrial, saprobic ecology as ancestral. In contrast to previous studies, these analyses support multiple origins of lichenization events with the loss of lichenization as less frequent and limited to terminal, closely related species.
Luciano Reis Venturoso - One of the best experts on this subject based on the ideXlab platform.
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Soybean production and carpogenic germination of Sclerotinia sclerotiorum under different cover cropsProdução de soja e germinação carpogênica de Sclerotinia sclerotiorum sob diferentes coberturas de solo
Universidade Estadual de Londrina, 2013Co-Authors: Luciano Reis Venturoso, Lilian Maria Arruda Bacchi, Walber Luiz Gavassoni, Daniel Luan Pereira Espindola, João Aparecido Eugênio Dos SantosAbstract:The aim of this work was to evaluate the influence of different soil cover crops on the carpogenic germination of Sclerotinia sclerotiorum and the development and yield of soybean. The treatments consisted of mulches of brachiaria, canola, safflower, crambe, sunflower and forage radish mulch, and a control with no cover mulch. The crops were sown in pots containing 4.4 dm³ of soil type Rhodic Acrustox. After 45 days the plant material was cut into pieces in order to standardize the amount of straw to 2800 kg ha-1. Soybean seeds were sown and seven days after seedling emergence two sclerotia were allocated in each pot. With regard to carpogenic germination, we analyzed the time to germination of sclerotia and formation of apothecia, number of stipes and apothecia per sclerotia and the percentage apothecia formed. In the soybean crop was determined plant height at flowering and harvest, relative chlorophyll index, dry matter mass and root, number of pods per plant, number of seeds per pod, grain yield, number of nodules per plant and dry mass of nodules. With the exception of safflower mulch, the use of cover crops reduced the formation of stipes and apothecia of S. sclerotiorum. The covers with brachiaria, sunflower and forage radish mulch increased by 16, 10 and 6 days respectively the overall period of Apothecium formation, but only brachiaria reduced the percentage of apothecia formed. The sunflower mulch hindered soybean development and yield. O trabalho teve por objetivo avaliar a influência de diferentes coberturas vegetais de solo sobre a germinação carpogênica de Sclerotinia sclerotiorum e sobre o desenvolvimento e rendimento da cultura da soja. Os tratamentos constaram da palhada de braquiária, canola, cártamo, crambe, girassol e nabo forrageiro, mais um controle sem cobertura. As culturas de cobertura foram semeadas em vasos contendo 4,4 dm³ de solo do tipo Latossolo Vermelho Distroférrico. Após 45 dias o material vegetal foi cortado em pedaços de modo a padronizar a quantidade de palha para 2800 kg ha-1. Posteriormente, sementes de soja foram semeadas e sete dias após a emergência das plântulas foram alocados dois escleródios de S. sclerotiorum por vaso. Em relação à germinação carpogênica, foi analisado o tempo para a germinação dos escleródios e formação dos apotécios, número de estipes e apotécios por escleródio e a porcentagem de apotécios formados. Na cultura da soja foi determinada a altura de plantas no florescimento e na colheita, índice relativo de clorofila, massa seca da parte aérea e de raiz, número de vagens por planta, número de sementes por vagem, rendimento, número de nódulos por planta e a massa seca de nódulos. Com exceção ao cártamo, constatou-se que o uso de cobertura vegetal do solo reduziu a formação de estipes e apotécios de S. sclerotiorum. As coberturas com braquiária, girassol e nabo forrageiro aumentaram em 16, 10 e 6 dias respectivamente o período para a formação do apotécio, porém, somente braquiária reduziu a porcentagem de apotécios formados. A cobertura do solo com palha de girassol prejudicou o desenvolvimento e o rendimento da cultura da soja
Hideyuki Nagao - One of the best experts on this subject based on the ideXlab platform.
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First report of pteridocolous discomycetes, Lachnum lanariceps and L. oncospermatum, on decayed tree fern in Bukit Bendera (Penang Hill), Pulau Pinang, Malaysia
Prince of Songkla University, 2014Co-Authors: Muhammad Zulfa Mohd Razikin, Hideyuki Nagao, Rahmad ZakariaAbstract:Bukit Bendera is 833 m above sea level and situated in the Northern part of Penang Island, Malaysia. Generally an average temperature is between 20 to 27°C, which is about 5°C cooler than at the sea level. The hill dipterocarp forest dominates Bukit Bendera and tree fern scatteredly grows at higher altitude. Two Lachnum spp. were observed as pteridocolous cup fungi on decayed rachides of several tree fern species, Cyathea contaminans, C. latebrosa, and C. hymenodes. Lachnum oncospermatum is characterized by a wrinkled Apothecium and branched stipe. The hairs contain brown colored resinous materials and are finely granulated. Lachnum lanariceps is characterized by a central and cylindrical stipe and hairs containing pale yellow pigment with red or garnet resinous matter. These two Lachnum species are new to Malaysia
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discomycetes on decayed tree fern 3 lachnum lanariceps and lachnum oncospermatum new to japan
Mycoscience, 2008Co-Authors: Hideyuki NagaoAbstract:Two species were newly identified in Japan. Lachnum lanariceps was characterized by a central and cylindrical stipe and hairs containing pale yellow pigment with red or garnet resinous matter. Lachnum oncospermatum was identified after comparison with the holotype of Dasyscyphus oncospermatis. This fungus has the characteristics of wrinkled Apothecium and branched stipe.