The velvet protein Vel1 controls initial plant root colonization and conidia formation for xylem distribution in Verticillium wilt

The conserved fungal velvet family regulatory proteins link development and secondary metabolite production. The velvet domain for DNA binding and dimerization is similar to the structure of the Rel homology domain of the mammalian NF-κB transcription factor. A comprehensive study addressed the functions of all four homologs of velvet domain encoding genes in the fungal life cycle of the soil-borne plant pathogenic fungus Verticillium dahliae. Genetic, cell biological, proteomic and metabolomic analyses of Vel1, Vel2, Vel3 and Vos1 were combined with plant pathogenicity experiments. Different phases of fungal growth, development and pathogenicity require V. dahliae velvet proteins, including Vel1-Vel2, Vel2-Vos1 and Vel3-Vos1 heterodimers, which are already present during vegetative hyphal growth. The major novel finding of this study is that Vel1 is necessary for initial plant root colonization and together with Vel3 for propagation in planta by conidiation. Vel1 is needed for disease symptom induction in tomato. Vel1, Vel2, and Vel3 control the formation of microsclerotia in senescent plants. Vel1 is the most important among all four V. dahliae velvet proteins with a wide variety of functions during all phases of the fungal life cycle in as well as ex planta.

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Potential Role of Flavobacterial Gliding-Motility and Type IX Secretion System Complex in Root Colonization and Plant Defense

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-03-14-0067-r ◽

2014 ◽

Vol 27 (9) ◽

pp. 1005-1013 ◽

Cited By ~ 24

Author(s):

Max Kolton ◽

Omer Frenkel ◽

Yigal Elad ◽

Eddie Cytryn

Keyword(s):

Plant Defense ◽

Root Colonization ◽

Plant Protection ◽

Plant Root ◽

Secretion System ◽

Gliding Motility ◽

Wild Type ◽

In Planta ◽

Clavibacter Michiganensis

Members of the Flavobacterium genus are often highly abundant in the rhizosphere. Nevertheless, the physiological characteristics associated with their enhanced rhizosphere competence are currently an enigma. Flavobacteria possess a unique gliding-motility complex that is tightly associated with a recently characterized Bacteroidetes-specific type IX protein secretion system, which distinguishes them from the rest of the rhizosphere microbiome. We hypothesize that proper functionality of this complex may confer a competitive advantage in the rhizosphere. To test this hypothesis, we constructed mutant and complement root-associated flavobacterial variants with dysfunctional secretion and gliding motility, and tested them in a series of in planta experiments. These mutants demonstrated significantly lower rhizosphere persistence (approximately 10-fold), plant root colonization (approximately fivefold), and seed adhesion capacity (approximately sevenfold) than the wild-type strains. Furthermore, the biocontrol capacity of the mutant strain toward foliar-applied Clavibacter michiganensis was significantly impaired relative to the wild-type strain, suggesting a role of the gliding and secretion complex in plant protection. Collectively, these results provide an initial link between the high abundance of flavobacteria in the rhizosphere and their unique physiology, indicating that the flavobacterial gliding-motility and secretion complex may play a central role in root colonization and plant defense.

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Faculty Opinions recommendation of LapF, the second largest Pseudomonas putida protein, contributes to plant root colonization and determines biofilm architecture.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.3744960.3848054 ◽

2010 ◽

Author(s):

Ben Lugtenberg

Keyword(s):

Pseudomonas Putida ◽

Root Colonization ◽

Plant Root ◽

Biofilm Architecture

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Cysteine-Rich Hydrophobin Gene Family: Genome Wide Analysis, Phylogeny and Transcript Profiling in Cordyceps militaris

International Journal of Molecular Sciences ◽

10.3390/ijms22020643 ◽

2021 ◽

Vol 22 (2) ◽

pp. 643

Author(s):

Xiao Li ◽

Fen Wang ◽

Yanyan Xu ◽

Guijun Liu ◽

Caihong Dong

Keyword(s):

Life Cycle ◽

Pathogenic Fungi ◽

Class Ii ◽

Cordyceps Militaris ◽

Transcript Profiling ◽

Saprotrophic Fungi ◽

Genome Wide Analysis ◽

Genome Wide ◽

Encoding Genes

Hydrophobins are a family of small secreted proteins found exclusively in fungi, and they play various roles in the life cycle. In the present study, genome wide analysis and transcript profiling of the hydrophobin family in Cordyceps militaris, a well-known edible and medicinal mushroom, were studied. The distribution of hydrophobins in ascomycetes with different lifestyles showed that pathogenic fungi had significantly more hydrophobins than saprotrophic fungi, and class II members accounted for the majority. Phylogenetic analysis of hydrophobin proteins from the species of Cordyceps s.l. indicated that there was more variability among the class II members than class I. Only a few hydrophobin-encoding genes evolved by duplication in Cordyceps s.l., which was inconsistent with the important role of gene duplication in basidiomycetes. Different transcript patterns of four hydrophobin-encoding genes during the life cycle indicated the possible different functions for each. The transcripts of Cmhyd2, 3 and 4 can respond to light and were related with the photoreceptors. CmQHYD, with four hydrophobin II domains, was first found in C. militaris, and multi-domain hydrophobins were only distributed in the species of Cordycipitaceae and Clavicipitaceae. These results could be helpful for further function research of hydrophobins and could provide valuable information for the evolution of hydrophobins.

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Characterization of the mbsA Gene Encoding a Putative APSES Transcription Factor in Aspergillus fumigatus

International Journal of Molecular Sciences ◽

10.3390/ijms22073777 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3777

Author(s):

Yong-Ho Choi ◽

Sang-Cheol Jun ◽

Min-Woo Lee ◽

Jae-Hyuk Yu ◽

Kwang-Soo Shin

Keyword(s):

Aspergillus Fumigatus ◽

Pathogenic Fungus ◽

Hyphal Growth ◽

Spore Wall ◽

Mrna Levels ◽

Chitin Synthesis ◽

Helix Loop Helix ◽

Growth Development ◽

Opportunistic Pathogenic

The APSES family proteins are transcription factors (TFs) with a basic helix-loop-helix domain, known to regulate growth, development, secondary metabolism, and other biological processes in Aspergillus species. In the genome of the human opportunistic pathogenic fungus Aspergillus fumigatus, five genes predicted to encode APSES TFs are present. Here, we report the characterization of one of these genes, called mbsA (Afu7g05620). The deletion (Δ) of mbsA resulted in significantly decreased hyphal growth and asexual sporulation (conidiation), and lowered mRNA levels of the key conidiation genes abaA, brlA, and wetA. Moreover, ΔmbsA resulted in reduced spore germination rates, elevated sensitivity toward Nikkomycin Z, and significantly lowered transcripts levels of genes associated with chitin synthesis. The mbsA deletion also resulted in significantly reduced levels of proteins and transcripts of genes associated with the SakA MAP kinase pathway. Importantly, the cell wall hydrophobicity and architecture of the ΔmbsA asexual spores (conidia) were altered, notably lacking the rodlet layer on the surface of the ΔmbsA conidium. Comparative transcriptomic analyses revealed that the ΔmbsA mutant showed higher mRNA levels of gliotoxin (GT) biosynthetic genes, which was corroborated by elevated levels of GT production in the mutant. While the ΔmbsA mutant produced higher amount of GT, ΔmbsA strains showed reduced virulence in the murine model, likely due to the defective spore integrity. In summary, the putative APSES TF MbsA plays a multiple role in governing growth, development, spore wall architecture, GT production, and virulence, which may be associated with the attenuated SakA signaling pathway.

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The Effect of Fusarium verticillioides Fumonisins on Fatty Acids, Sphingolipids, and Oxylipins in Maize Germlings

International Journal of Molecular Sciences ◽

10.3390/ijms22052435 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2435

Author(s):

Marzia Beccaccioli ◽

Manuel Salustri ◽

Valeria Scala ◽

Matteo Ludovici ◽

Andrea Cacciotti ◽

...

Keyword(s):

Fatty Acids ◽

Fusarium Verticillioides ◽

Fungal Growth ◽

Defense Responses ◽

Ceramide Synthase ◽

Ear Rot ◽

In Planta ◽

Disease Symptoms ◽

The Impact

Fusarium verticillioides causes multiple diseases of Zea mays (maize) including ear and seedling rots, contaminates seeds and seed products worldwide with toxic chemicals called fumonisins. The role of fumonisins in disease is unclear because, although they are not required for ear rot, they are required for seedling diseases. Disease symptoms may be due to the ability of fumonisins to inhibit ceramide synthase activity, the expected cause of lipids (fatty acids, oxylipins, and sphingolipids) alteration in infected plants. In this study, we explored the impact of fumonisins on fatty acid, oxylipin, and sphingolipid levels in planta and how these changes affect F. verticillioides growth in maize. The identity and levels of principal fatty acids, oxylipins, and over 50 sphingolipids were evaluated by chromatography followed by mass spectrometry in maize infected with an F. verticillioides fumonisin-producing wild-type strain and a fumonisin-deficient mutant, after different periods of growth. Plant hormones associated with defense responses, i.e., salicylic and jasmonic acid, were also evaluated. We suggest that fumonisins produced by F. verticillioides alter maize lipid metabolism, which help switch fungal growth from a relatively harmless endophyte to a destructive necrotroph.

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Deletion of Rap‐Phr systems in Bacillus subtilis influences in vitro biofilm formation and plant root colonization

MicrobiologyOpen ◽

10.1002/mbo3.1212 ◽

2021 ◽

Vol 10 (3) ◽

Author(s):

Mathilde Nordgaard ◽

Rasmus Møller Rosenbek Mortensen ◽

Nikolaj Kaae Kirk ◽

Ramses Gallegos‐Monterrosa ◽

Ákos T. Kovács

Keyword(s):

Bacillus Subtilis ◽

Biofilm Formation ◽

Root Colonization ◽

Plant Root

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In Silico Analyses of Rice Thionin Genes and the Antimicrobial Activity of OsTHION15 Against Phytopathogens

Phytopathology ◽

10.1094/phyto-06-17-0217-r ◽

2019 ◽

Vol 109 (1) ◽

pp. 27-35

Author(s):

Krissana Boonpa ◽

Suparuk Tantong ◽

Kamonwan Weerawanich ◽

Pawinee Panpetch ◽

Onanong Pringsulaka ◽

...

Keyword(s):

Antimicrobial Activity ◽

Stress Responses ◽

In Silico ◽

Pathogenic Bacteria ◽

Hyphal Growth ◽

In Planta ◽

Recombinant Peptide ◽

Plant Disease Control ◽

Helminthosporium Oryzae ◽

In Silico Analyses

Thionins are a family of antimicrobial peptides. We performed in silico expression analyses of the 44 rice (Oryza sativa) thionins (OsTHIONs). Modulated expression levels of OsTHIONs under different treatments suggest their involvement in many processes, including biotic, abiotic, and nutritional stress responses, and in hormone signaling. OsTHION15 (LOC_Os06g32600) was selected for further characterization based on several in silico analyses. OsTHION15 in O. sativa subsp. indica ‘KDML 105’ was expressed in all of the tissues and organs examined, including germinating seed, leaves, and roots of seedlings and mature plants, and inflorescences. To investigate the antimicrobial activity of OsTHION15, we produced a recombinant peptide in Escherichia coli Rosetta-gami (DE3). The recombinant OsTHION15 exhibited inhibitory activities toward rice-pathogenic bacteria such as Xanthomonas oryzae pv. oryzae and Pectobacterium carotovorum pv. atroseptica, with minimum inhibitory concentrations of 112.6 and 14.1 µg ml−1, respectively. A significant hyphal growth inhibition was also observed toward Fusarium oxysporum f. sp. cubense and Helminthosporium oryzae. In addition, we demonstrated the in planta antibacterial activity of this peptide in Nicotiana benthamiana against X. campestris pv. glycines. These activities suggest the possible application of OsTHION15 in plant disease control.

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Transcription Profiling ofCandida albicansCells Undergoing the Yeast-to-Hyphal Transition

Molecular Biology of the Cell ◽

10.1091/mbc.e02-05-0272 ◽

2002 ◽

Vol 13 (10) ◽

pp. 3452-3465 ◽

Cited By ~ 271

Author(s):

André Nantel ◽

Daniel Dignard ◽

Catherine Bachewich ◽

Doreen Harcus ◽

Anne Marcil ◽

...

Keyword(s):

Time Course ◽

Dna Microarrays ◽

Culture Medium ◽

Developmental Process ◽

Pathogenic Fungus ◽

Hyphal Growth ◽

Transcription Profiles ◽

Hyphal Morphology ◽

External Signals ◽

Temperature Time

The ability of the pathogenic fungus Candida albicans to switch from a yeast to a hyphal morphology in response to external signals is implicated in its pathogenicity. We used glass DNA microarrays to investigate the transcription profiles of 6333 predicted ORFs in cells undergoing this transition and their responses to changes in temperature and culture medium. We have identified several genes whose transcriptional profiles are similar to those of known virulence factors that are modulated by the switch to hyphal growth caused by addition of serum and a 37°C growth temperature. Time course analysis of this transition identified transcripts that are induced before germ tube initiation and shut off later in the developmental process. A strain deleted for the Efg1p and Cph1p transcription factors is defective in hyphae formation, and its response to serum and increased temperature is almost identical to the response of a wild-type strain grown at 37°C in the absence of serum. Thus Efg1p and Cph1p are needed for the activation of the transcriptional program that is induced by the presence of serum.

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Cell Wall-Related Bionumbers and Bioestimates of Saccharomyces cerevisiae and Candida albicans

Eukaryotic Cell ◽

10.1128/ec.00250-13 ◽

2013 ◽

Vol 13 (1) ◽

pp. 2-9 ◽

Cited By ~ 58

Author(s):

Frans M. Klis ◽

Chris G. de Koster ◽

Stanley Brul

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Wall ◽

Candida Albicans ◽

Cell Size ◽

Pathogenic Fungus ◽

Turgor Pressure ◽

Hyphal Growth ◽

Biological Research ◽

Content Type ◽

Starting Point

ABSTRACTBionumbers and bioestimates are valuable tools in biological research. Here we focus on cell wall-related bionumbers and bioestimates of the budding yeastSaccharomyces cerevisiaeand the polymorphic, pathogenic fungusCandida albicans. We discuss the linear relationship between cell size and cell ploidy, the correlation between cell size and specific growth rate, the effect of turgor pressure on cell size, and the reason why using fixed cells for measuring cellular dimensions can result in serious underestimation ofin vivovalues. We further consider the evidence that individual buds and hyphae grow linearly and that exponential growth of the population results from regular formation of new daughter cells and regular hyphal branching. Our calculations show that hyphal growth allowsC. albicansto cover much larger distances per unit of time than the yeast mode of growth and that this is accompanied by strongly increased surface expansion rates. We therefore predict that the transcript levels of genes involved in wall formation increase during hyphal growth. Interestingly, wall proteins and polysaccharides seem barely, if at all, subject to turnover and replacement. A general lesson is how strongly most bionumbers and bioestimates depend on environmental conditions and genetic background, thus reemphasizing the importance of well-defined and carefully chosen culture conditions and experimental approaches. Finally, we propose that the numbers and estimates described here offer a solid starting point for similar studies of other cell compartments and other yeast species.

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