Faculty Opinions recommendation of Analysis of Repeat Induced Point (RIP) Mutations in Leptosphaeria maculans Indicates Variability in the RIP Process Between Fungal Species.

Maculansins, Cryptic Phytotoxins from Blackleg Fungi

Natural Product Communications ◽

10.1177/1934578x1100600509 ◽

2011 ◽

Vol 6 (5) ◽

pp. 1934578X1100600

Author(s):

M. Soledade C. Pedras ◽

Paulos B. Chumala

Keyword(s):

Leptosphaeria Maculans ◽

Culture Conditions ◽

Fungal Species ◽

Metabolic Characteristics ◽

The Common

The phytotoxins and other metabolites produced by isolates L2/M2 of the fungal species Leptosphaeria maculans under different culture conditions, together with those of two new, but related isolates are disclosed. The common metabolic characteristics suggest a phylogenetic similarity between these isolates with potential to become widespread in mustard growing areas.

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Phytotoxins, Elicitors and Other Secondary Metabolites from Phytopathogenic “Blackleg” Fungi: Structure, Phytotoxicity and Biosynthesis

Natural Product Communications ◽

10.1177/1934578x0900400927 ◽

2009 ◽

Vol 4 (9) ◽

pp. 1934578X0900400 ◽

Cited By ~ 2

Author(s):

M. Soledade C. Pedras ◽

Yang Yu

Keyword(s):

Secondary Metabolites ◽

Leptosphaeria Maculans ◽

Culture Conditions ◽

Fungal Species ◽

Biosynthetic Studies

The metabolites produced by the fungal species Leptosphaeria maculans and L. biglobosa under different culture conditions, together with their phytotoxic activities are reviewed. In addition, the biosynthetic studies of blackleg metabolites carried out to date are described and suggestions for species reclassification are provided.

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Impact of Cruciferous Phytoalexins on the Detoxification of Brassilexin by the Blackleg Fungus Pathogenic to Brown Mustard

Natural Product Communications ◽

10.1177/1934578x1000500612 ◽

2010 ◽

Vol 5 (6) ◽

pp. 1934578X1000500

Author(s):

M. Soledade C. Pedras ◽

Ryan B. Snitynsky

Keyword(s):

Brassica Juncea ◽

Leptosphaeria Maculans ◽

Fungal Species ◽

Important Group ◽

Blackleg Fungus

The biotransformation of brassilexin, a potent phytoalexin produced by brown mustard (Brassica juncea L.), in the presence of various cruciferous phytoalexins was investigated. An important group of isolates of the fungal species Leptosphaeria maculans (Laird 2 and Mayfair 2), which is virulent to brown mustard, but not to canola, was used in this investigation. Brassilexin was detoxified by the fungus, but none of the phytoalexins seemed to affect substantially the rate of brassilexin detoxification; after 12 h of incubation, the amounts of brassilexin remaining in culture were as low as in controls, except in co-incubations with cyclobrassinin and sinalexin, which afforded intermediates that in solution oxidized spontaneously to brassilexin.

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Induced Resistance to Blackleg (Leptosphaeria maculans) Disease of Canola (Brassica napus) Caused by a Weakly Virulent Isolate of Leptosphaeria biglobosa

Plant Disease ◽

10.1094/pd-90-1059 ◽

2006 ◽

Vol 90 (8) ◽

pp. 1059-1064 ◽

Cited By ~ 12

Author(s):

Y. Chen ◽

W. G. D. Fernando

Keyword(s):

Brassica Napus ◽

Field Experiments ◽

Leptosphaeria Maculans ◽

Fungal Species ◽

Control Treatment ◽

Water Control ◽

Pathogenicity Group ◽

Weakly Virulent ◽

Leptosphaeria Biglobosa ◽

Highly Virulent

Blackleg of canola is a disease complex of at least two fungal species: Leptosphaeria maculans and L. biglobosa. Isolates of L. biglobosa typically are weakly virulent or avirulent and are assigned to pathogenicity group 1 (PG-1). Isolates of L. maculans are highly virulent and encompass pathogenicity groups PG-2, PG-3, and PG-4. In greenhouse tests, percent lesion/leaf area (PLLA) on cotyledons of two Brassica napus cultivars, Westar and Invigor 2153, was smaller when L. biglobosa (PG-1) was either pre- or co-inoculated at 0, 12, 24, and 48 h with virulent isolates of L. maculans in PG-2, PG-3, and PG-4. On six-leaf-stage plants of Westar, the PLLA declined significantly compared with the control when the lower leaves were treated with either PG-1 or salicylic acid, then challenged with a PG-2 isolate 24 h later. In addition, the activity of four enzymes (chitinase, β-1,3-glucanase, peroxidase, and phenylalanine ammonia lyase) was greatly enhanced at 48 and 72 h when cotyledons of Westar were inoculated first with PG-1 followed by PG-2 24 h later, compared with a water control treatment. Field experiments conducted in 2003 and 2004 showed decreased blackleg severity in plants inoculated with PG-1 alone or prior to PG-2 compared with plants inoculated with PG-2 alone or prior to PG-1.

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Genome-Wide Mapping of Histone Modifications in Two Species of Leptosphaeria Maculans Showing Contrasting Genomic Organization and Host Specialization

10.21203/rs.3.rs-73550/v1 ◽

2020 ◽

Author(s):

Jessica Louise Soyer ◽

Colin Clairet ◽

Elise J. Gay ◽

Nicolas Lapalu ◽

Thierry Rouxel ◽

...

Keyword(s):

Histone Modifications ◽

Genome Structure ◽

Leptosphaeria Maculans ◽

Axenic Culture ◽

Selective Advantage ◽

Fungal Species ◽

Host Specialization ◽

Plant Infection ◽

Effector Genes ◽

Species Specific

Abstract BackgroundIn plant-associated fungi, the epigenome is increasingly recognized as an important regulator of the expression of genes involved in interaction with the host plant. Leptosphaeria maculans ‘brassicae’ (Lmb) and Leptosphaeria maculans ‘lepidii’ (Lml) are closely-related phytopathogenic species that exhibit a large macrosynteny but contrasting genome structure. Lmb has more than 30% of repeats clustered in large repeat-rich regions, while the Lml genome has only a small amount of evenly distributed repeats. Repeat-rich regions of Lmb are enriched in effector genes, expressed during plant infection. The distinct genome structures of Lmb and Lml provide an excellent model for comparing the organization of pathogenicity genes in relation to the chromatin landscape in two closely related phytopathogenic fungi. Here, we performed chromatin immunoprecipitation (ChIP) during axenic culture, targeting histone modifications typical for heterochromatin or euchromatin, combined with transcriptomic analysis to analyse the influence of chromatin organisation on gene expression.ResultsIn both species, we found that facultative heterochromatin are enriched with genes lacking functional annotation, including numerous effector and species-specific genes. Notably, orthologous genes located in H3K27me3-domains are enriched with effector genes. Compared to other fungal species, including Lml, Lmb is distinct in having large H3K9me3-domains associated with repeat-rich regions that contain numerous species-specific effector genes. ConclusionDiscovery of these two distinctive heterochromatin landscapes now raises questions about their involvement in the regulation of pathogenicity, the dynamics of these domains during plant infection, and the selective advantage to the fungus to host effector genes in H3K9me3- or H3K27me3-domains.

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Genome-wide mapping of histone modifications during axenic growth in two species of Leptosphaeria maculans showing contrasting genomic organization

Chromosome Research ◽

10.1007/s10577-021-09658-1 ◽

2021 ◽

Author(s):

Jessica L. Soyer ◽

Colin Clairet ◽

Elise J. Gay ◽

Nicolas Lapalu ◽

Thierry Rouxel ◽

...

Keyword(s):

Histone Modifications ◽

Genome Structure ◽

Leptosphaeria Maculans ◽

Axenic Culture ◽

Selective Advantage ◽

Fungal Species ◽

Phytopathogenic Fungi ◽

Plant Infection ◽

Effector Genes ◽

Species Specific

AbstractLeptosphaeria maculans ‘brassicae’ (Lmb) and Leptosphaeria maculans ‘lepidii’ (Lml) are closely related phytopathogenic species that exhibit a large macrosynteny but contrasting genome structure. Lmb has more than 30% of repeats clustered in large repeat-rich regions, while the Lml genome has only a small amount of evenly distributed repeats. Repeat-rich regions of Lmb are enriched in effector genes, expressed during plant infection. The distinct genome structures of Lmb and Lml provide an excellent model for comparing the organization of pathogenicity genes in relation to the chromatin landscape in two closely related phytopathogenic fungi. Here, we performed chromatin immunoprecipitation (ChIP) during axenic culture, targeting histone modifications typical for heterochromatin or euchromatin, combined with transcriptomic analysis to analyze the influence of chromatin organization on gene expression. In both species, we found that facultative heterochromatin is enriched with genes lacking functional annotation, including numerous effector and species-specific genes. Notably, orthologous genes located in H3K27me3 domains are enriched with effector genes. Compared to other fungal species, including Lml, Lmb is distinct in having large H3K9me3 domains associated with repeat-rich regions that contain numerous species-specific effector genes. Discovery of these two distinctive heterochromatin landscapes now raises questions about their involvement in the regulation of pathogenicity, the dynamics of these domains during plant infection and the selective advantage to the fungus to host effector genes in H3K9me3 or H3K27me3 domains.

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