Project description:Members of the fungal genus Armillaria are necrotrophic pathogens with efficient plant biomass-degrading strategies. Armillaria species are some of the largest terrestrial organisms on Earth that cause tremendous losses in diverse ecosystems. Despite their global importance, how Armillaria evolved pathogenicity in a clade of dominantly non-pathogenic wood-degraders (Agaricales) remains elusive. Here, using new genomic data, we show that Armillaria species, in addition to widespread gene duplications and de novo gene origins, appear to have acquired at least 1025 genes via 124 horizontal gene transfer (HGT) events, primarily from Ascomycota donors. Functional and expression data suggest that HGT might have affected plant biomass-degrading and virulence abilities of Armillaria, two pivotal traits in their lifestyle. HGT provides an explanation for their soft-rot like biomass degrading strategy too, which is markedly different from the primarily white rot decay mechanism of related species. Combined multi-species expression data revealed putative virulence factors, extensive regulation of horizontally acquired and wood-decay related genes as well as novel noserved pathogenicity-induced small secreted proteins (PiSSPs). Two PiSSPs induced necrosis in live plants, suggesting they are potential virulence effectors conserved across Armillaria. Overall, this study details how evolution knitted together horizontally and vertically inherited genes in complex adaptive traits, such as plant biomass degradation and pathogenicityin one of the most influential fungal pathogens of temperate forest ecosystems.
Project description:Members of the fungal genus Armillaria are necrotrophic pathogens with efficient plant biomass-degrading strategies. Armillaria species are some of the largest terrestrial organisms on Earth that cause tremendous losses in diverse ecosystems. Despite their global importance, how Armillaria evolved pathogenicity in a clade of dominantly non-pathogenic wood-degraders (Agaricales) remains elusive. Here, using new genomic data, we show that Armillaria species, in addition to widespread gene duplications and de novo gene origins, acquired at least 1,025 genes via 124 horizontal gene transfer (HGT) events, primarily from Ascomycota donors. Functional and expression data suggest that HGT might have affected plant biomass-degrading and virulence abilities of Armillaria, two pivotal traits in their lifestyle. HGT provides an explanation for their soft-rot like biomass degrading strategy, which is which is markedly different from the primarily white rot decay mechanism of related species. Combined multi-species expression data revealed extensive regulation of horizontally acquired and wood-decay related genes, putative virulence factors as well as novel conserved pathogenicity-induced small secreted proteins (PiSSPs), two of which were experimentally verified to induce necrosis in live plants. Overall, this study details how evolution knitted together horizontally and vertically inherited genes in complex adaptive traits, such as plant biomass degradation and pathogenicity in one of the most influential fungal pathogens of temperate forest ecosystems.
Project description:Members of the fungal genus Armillaria are necrotrophic pathogens with efficient plant biomass-degrading strategies. Armillaria species are some of the largest terrestrial organisms on Earth that cause tremendous losses in diverse ecosystems. Despite their global importance, how Armillaria evolved pathogenicity in a clade of dominantly non-pathogenic wood-degraders (Agaricales) remains elusive. Here, using new genomic data, we show that Armillaria species, in addition to widespread gene duplications and de novo gene origins, appear to have acquired at least 1025 genes via 124 horizontal gene transfer (HGT) events, primarily from Ascomycota donors. Functional and expression data suggest that HGT might have affected plant biomass-degrading and virulence abilities of Armillaria, two pivotal traits in their lifestyle. HGT provides an explanation for their soft-rot like biomass degrading strategy too, which is markedly different from the primarily white rot decay mechanism of related species. Combined multi-species expression data revealed putative virulence factors, extensive regulation of horizontally acquired and wood-decay related genes as well as novel noserved pathogenicity-induced small secreted proteins (PiSSPs). Two PiSSPs induced necrosis in live plants, suggesting they are potential virulence effectors conserved across Armillaria. Overall, this study details how evolution knitted together horizontally and vertically inherited genes in complex adaptive traits, such as plant biomass degradation and pathogenicityin one of the most influential fungal pathogens of temperate forest ecosystems.
Project description:Members of the fungal genus Armillaria are necrotrophic pathogens with efficient plant biomass-degrading strategies. Armillaria species are some of the largest terrestrial organisms on Earth that cause tremendous losses in diverse ecosystems. Despite their global importance, how Armillaria evolved pathogenicity in a clade of dominantly non-pathogenic wood-degraders (Agaricales) remains elusive. Here, using new genomic data, we show that Armillaria species, in addition to widespread gene duplications and de novo gene origins, appear to have acquired at least 1025 genes via 124 horizontal gene transfer (HGT) events, primarily from Ascomycota donors. Functional and expression data suggest that HGT might have affected plant biomass-degrading and virulence abilities of Armillaria, two pivotal traits in their lifestyle. HGT provides an explanation for their soft-rot like biomass degrading strategy too, which is markedly different from the primarily white rot decay mechanism of related species. Combined multi-species expression data revealed putative virulence factors, extensive regulation of horizontally acquired and wood-decay related genes as well as novel noserved pathogenicity-induced small secreted proteins (PiSSPs). Two PiSSPs induced necrosis in live plants, suggesting they are potential virulence effectors conserved across Armillaria. Overall, this study details how evolution knitted together horizontally and vertically inherited genes in complex adaptive traits, such as plant biomass degradation and pathogenicityin one of the most influential fungal pathogens of temperate forest ecosystems.
Project description:Aliivibrio wodanis and Moritella viscosa have often been isolated together from fish with winter ulcer. Little is known about the interaction between the two bacterial species and how the presence of one bacterial species affects the behaviour of the other. The impact on bacterial growth in co-culture was investigated in vitro, and the presence of A. wodanis has a strong inhibitorial effect on M. viscosa. Further, we have sequenced the complete genomes of these two marine Gram-negative species, and have performed transcriptome analysis of the bacterial gene expression levels from in vivo samples. Using bacterial implants in the fish abdomen, we demonstrate that the presence of A. wodanis is altering the gene expression levels of M. viscosa compared to when the bacteria are implanted separately. The impeding effect on growth and the change in the global gene expression pattern of M. viscosa when the two pathogens co-exists is discussed in this paper.
Project description:Corals especially the reef-building species are very important to marine ecosystems. Proteomics has been used for researches on coral diseases, bleaching and responses to the environment change. Corals especially the reef-building species are very important to marine ecosystems. Proteomics has been used for researches on coral diseases, bleaching and responses to the environment change. In the present study, five protocols were compared for protein extraction from stony corals.
Project description:Macroalgae contribute substantially to primary production in coastal ecosystems. Their biomass, mainly consisting of polysaccharides, is cycled into the environment by marine heterotrophic bacteria (MHB), using largely uncharacterized mechanisms. In Zobellia galactanivorans, we discovered and characterized the complete catabolic pathway for carrageenans, major cell wall polysaccharides of red macroalgae, providing a model system for carrageenan utilization by MHB. We further demonstrate that carrageenan catabolism relies on a multifaceted carrageenan-induced regulon, including a non-canonical polysaccharide utilization locus (PUL) and several distal genes. The genetic structure of the carrageenan utilization system is well conserved in marine Bacteroidetes, but modified in other MHB phyla. The core system is completed by additional functions which can be assumed by non-orthologous genes in different species. This complex genetic structure is due to multiple evolutionary events including gene duplications and horizontal gene transfers. These results allow for an extension on the definition of bacterial PUL-mediated polysaccharide digestion.
2017-12-06 | GSE101142 | GEO
Project description:Soil bacterial community diversity in warm-temperate montane ecosystems