scholarly journals Fungal Pathogen Emergence: Investigations with an Ustilago maydis × Sporisorium reilianum Hybrid

2021 ◽  
Vol 7 (8) ◽  
pp. 672
Author(s):  
Emilee R. M. Storfie ◽  
Barry J. Saville
Keyword(s):  
Zea Mays ◽  
Fungal Pathogen ◽  
Fungal Pathogens ◽  
Crop Production ◽  
Virulence Genes ◽  
Ustilago Maydis ◽  
Smut Fungi ◽  
Transcript Levels ◽  
Sporisorium Reilianum ◽  
Molecular Aspects

The emergence of new fungal pathogens threatens sustainable crop production worldwide. One mechanism by which new pathogens may arise is hybridization. To investigate hybridization, the related smut fungi, Ustilago maydis and Sporisorium reilianum, were selected because they both infect Zea mays, can hybridize, and tools are available for their analysis. The hybrid dikaryons of these fungi grew as filaments on plates but their colonization and virulence in Z. mays were reduced compared to the parental dikaryons. The anthocyanin induction caused by the hybrid dikaryon infections was distinct, suggesting its interaction with the host was different from that of the parental dikaryons. Selected virulence genes previously characterized in U. maydis and their predicted S. reilianum orthologs had altered transcript levels during hybrid infection of Z. mays. The downregulated U. maydis effectors, tin2, pit2, and cce1, and transcription factors, rbf1, hdp2, and nlt1, were constitutively expressed in the hybrid. Little impact was observed with increased effector expression; however, increased expression of rbf1 and hdp2, which regulate early pathogenic development by U. maydis, increased the hybrid’s capacity to induce symptoms including the rare induction of small leaf tumors. These results establish a base for investigating molecular aspects of smut fungal hybrid pathogen emergence.

scholarly journals Mating Type Loci of Sporisorium reilianum: Novel Pattern with Three a and Multiple b Specificities

2005 ◽  
Vol 4 (8) ◽  
pp. 1317-1327 ◽  
Author(s):  
Jan Schirawski ◽  
Bernadette Heinze ◽  
Martin Wagenknecht ◽  
Regine Kahmann
Keyword(s):  
Mating Type ◽  
Molecular Basis ◽  
Plant Invasion ◽  
Ustilago Maydis ◽  
Smut Fungi ◽  
Symptom Development ◽  
Receptor System ◽  
Mating Partner ◽  
Sporisorium Reilianum ◽  
High Degree

ABSTRACT Sporisorium reilianum and Ustilago maydis are two closely related smut fungi, which both infect maize but differ fundamentally in their mode of plant invasion and site of symptom development. As a prelude to studying the molecular basis of these differences, we have characterized the mating type loci of S. reilianum. S. reilianum has two unlinked mating type loci, a and b. Genes in both loci and adjacent regions show a high degree of synteny to the corresponding genes of U. maydis. The b locus occurs in at least five alleles and encodes two subunits of a heterodimeric homeodomain transcription factor, while the a locus encodes a pheromone/receptor system. However, in contrast to that of U. maydis, the a locus of S. reilianum exists in three alleles containing two active pheromone genes each. The alleles of the a locus appear to have arisen through recent recombination events within the locus itself. This has created a situation where each pheromone is specific for recognition by only one mating partner.

scholarly journals Cross-species analysis between the maize smut fungi Ustilago maydis and Sporisorium reilianum highlights the role of transcriptional plasticity of effector orthologs for virulence and disease

2020 ◽  
Author(s):  
Weiliang Zuo ◽  
Deepak K Gupta ◽  
Jasper RL Depotter ◽  
Marco Thines ◽  
Gunther Doehlemann
Keyword(s):  
Ustilago Maydis ◽  
Effector Proteins ◽  
Differentially Expressed ◽  
Transcriptional Level ◽  
Smut Fungi ◽  
List Type ◽  
Sequencing Analysis ◽  
Distinct Disease ◽  
Sporisorium Reilianum ◽  
Transcriptional Plasticity

SummaryThe constitution and regulation of effector repertoires determines and shapes the outcome of the interaction with the host. Ustilago maydis and Sporisorium reilianum are two closely related smut fungi, which both infect maize, but cause distinct disease symptoms. Understanding how effector orthologs are regulated in these two pathogens can therefore provide insights to pathogen evolution and host adaption.We tracked the infection progress of U. maydis and S. reilianum in maize leaves, characterized two distinct infection stages for cross species RNA-sequencing analysis and identified 207 out of 335 one-to-one effector orthologs being differentially regulated during host colonization, while transcriptional plasticity of the effector orthologs correlated with the distinct disease development strategies.By using CRISPR-Cas9 mediated gene conversion, we identified two differentially expressed effector orthologs with conserved function between two pathogens. Thus, differential expression of functionally conserved genes contributes to species specific adaptation and symptom development. Interestingly, another differentially expressed orthogroup (UMAG_05318/sr1007) showed diverged protein function during speciation, providing a possible case for neofunctionalization.Together, we showed the diversification of effector genes in related pathogens can be caused both by plasticity on the transcriptional level, as well as through neofunctionalization of the encoded effector proteins.

Molecular Interactions Between Smut Fungi and Their Host Plants

2019 ◽  
Vol 57 (1) ◽  
pp. 411-430 ◽  
Author(s):  
Weiliang Zuo ◽  
Bilal Ökmen ◽  
Jasper R.L. Depotter ◽  
Malaika K. Ebert ◽  
Amey Redkar ◽  
...  
Keyword(s):  
Cell Biology ◽  
Fungal Pathogens ◽  
Plant Pathogens ◽  
Functional Characterization ◽  
Model System ◽  
Future Research ◽  
Comparative Genomic ◽  
Smut Fungi ◽  
Sporisorium Reilianum ◽  
Genome Analyses

Smut fungi are a large group of biotrophic plant pathogens that infect mostly monocot species, including economically relevant cereal crops. For years, Ustilago maydis has stood out as the model system to study the genetics and cell biology of smut fungi as well as the pathogenic development of biotrophic plant pathogens. The identification and functional characterization of secreted effectors and their role in virulence have particularly been driven forward using the U. maydis–maize pathosystem. Today, advancing tools for additional smut fungi such as Ustilago hordei and Sporisorium reilianum, as well as an increasing number of available genome sequences, provide excellent opportunities to investigate in parallel the effector function and evolution associated with different lifestyles and host specificities. In addition, genome analyses revealed similarities in the genomic signature between pathogenic smuts and epiphytic Pseudozyma species. This review elaborates on how knowledge about fungal lifestyles, genome biology, and functional effector biology has helped in understanding the biology of this important group of fungal pathogens. We highlight the contribution of the U. maydis model system but also discuss the differences from other smut fungi, which raises the importance of comparative genomic and genetic analyses in future research.

Pathogenicity Determinants in Smut Fungi Revealed by Genome Comparison

Science ◽  
2010 ◽  
Vol 330 (6010) ◽  
pp. 1546-1548 ◽  
Author(s):  
Jan Schirawski ◽  
Gertrud Mannhaupt ◽  
Karin Münch ◽  
Thomas Brefort ◽  
Kerstin Schipper ◽  
...  
Keyword(s):  
Pathogenic Fungi ◽  
Ustilago Maydis ◽  
Genome Comparison ◽  
Smut Fungi ◽  
Plant Proteins ◽  
Virulence Determinants ◽  
Closely Related Species ◽  
Biotrophic Pathogens ◽  
Sporisorium Reilianum ◽  
Genomic Regions

Biotrophic pathogens, such as the related maize pathogenic fungi Ustilago maydis and Sporisorium reilianum, establish an intimate relationship with their hosts by secreting protein effectors. Because secreted effectors interacting with plant proteins should rapidly evolve, we identified variable genomic regions by sequencing the genome of S. reilianum and comparing it with the U. maydis genome. We detected 43 regions of low sequence conservation in otherwise well-conserved syntenic genomes. These regions primarily encode secreted effectors and include previously identified virulence clusters. By deletion analysis in U. maydis, we demonstrate a role in virulence for four previously unknown diversity regions. This highlights the power of comparative genomics of closely related species for identification of virulence determinants.

Ultrastructure of meiosis and the spindle pole body cycle in freeze-substituted basidia of the smut fungi Ustilago maydis and Ustilago avenae

1992 ◽  
Vol 70 (3) ◽  
pp. 629-638 ◽  
Author(s):  
Kerry O'Donnell
Keyword(s):  
Electron Microscopy ◽  
Spindle Pole Body ◽  
Ustilago Maydis ◽  
Spindle Pole ◽  
Meiotic Spindle ◽  
Smut Fungi ◽  
Late Prophase ◽  
Prophase I ◽  
Pole Body ◽  
Middle Piece

Meiosis in the smut fungi Ustilago maydis and Ustilago avenae (Basidiomycota, Ustilaginales) was studied by electron microscopy of serial-sectioned freeze substituted basidia. At prophase I, a spindle pole body composed of two globular elements connected by a middle piece was attached to the extranuclear surface of each nucleus. Astral and spindle microtubules were initiated at each globular element at late prophase I to prometaphase I. During spindle initiation, the middle piece disappeared and interdigitating half-spindles entered the nucleoplasm, which was surrounded by discontinuous nuclear envelope together with perinuclear endoplasmic reticulum. Kinetochore pairs at metaphase I were analyzed to obtain a karyotype for each species. The meiotic spindle pole body replicational cycle is described. Key words: electron microscopy, freeze-substitution, meiosis, Ustilago, spindle pole body.

Russian Thistle (Salsola iberica) and Kochia (Kochia scoparia) Control in Dryland Corn (Zea mays)

1990 ◽  
Vol 4 (3) ◽  
pp. 631-634 ◽  
Author(s):  
R. E. Blackshaw
Keyword(s):  
Zea Mays ◽  
Weed Control ◽  
Crop Production ◽  
Production Systems ◽  
Cropping System ◽  
Field Studies ◽  
Kochia Scoparia ◽  
Field Corn ◽  
Salsola Iberica

Field studies were conducted in 1987, 1988, and 1989 at Lethbridge, Alberta to determine suitable herbicides for the control of Russian thistle and kochia in field corn grown in a dryland cropping system. Soil-applied atrazine or cyanazine provided inconsistent control of these weeds under dryland conditions. Combining inter-row tillage or 2,4-D applied postemergence with soil-applied atrazine improved the consistency of weed control over years. Postemergence atrazine and dicamba plus 2,4-D controlled Russian thistle and kochia in all years. Corn yields reflected the level of weed control attained with each treatment. The suitability of the various treatments for weed control in corn grown under dryland crop production systems is discussed.

Catalytic and Molecular Aspects of the Functioning of Glutamate-Dehydrogenase Isoforms in Corn Zea mays L.

2021 ◽  
Vol 57 (2) ◽  
pp. 236-242
Author(s):  
A. T. Eprintsev ◽  
G. B. Anokhina ◽  
P. S. Oya ◽  
Ya. I. Dedov
Keyword(s):  
Zea Mays ◽  
Glutamate Dehydrogenase ◽  
Zea Mays L ◽  
Molecular Aspects
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