Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1138887 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Long-term coexistence between cyanobacteria and their lytic viruses (cyanophages) in the oceans is thought to be due to the presence of sensitive cells in which cyanophages reproduce, ultimately killing the cell, while other cyanobacteria survive due to resistance to infection. Here we investigated resistance strategies in naturally resistant cyanobacteria and compared strategies against generalist and specialist cyanophages. Resistance was extracellular in most interactions against specialist cyanophages, preventing entry into the cell. In contrast, resistance was intracellular in practically all interactions against generalist cyanophages. Intriguingly, the stage of intracellular arrest was interaction-specific, halting at various stages of the infection cycle. These findings unveil a heavy cost of promiscuous entry of generalist phages into non-host cells that is rarely paid by specialists, potential unknown mechanisms of intracellular resistance and that the range for viral-mediated horizontal gene transfer extends much beyond just hosts.
2019-08-12 | PXD013030 | Pride
Project description:The entomopathogen Metarhizium anisopliae contains strains with wide host ranges and specialist strains adapted to particular hosts. Patterns of gene duplication, divergence and deletion in three generalist and three specialist strains were investigated by heterologous hybridization of genomic DNA to genes from the generalist strain ARSEF 2575. Many sequences from 2575 that are highly conserved in fungi showed rapid evolution and loss in specialist Metarhizium genomes. Some poorly hybridizing genes in specialists were functionally coordinated, including several involved in toxin biosyntheses and sugar metabolism in root exudates, indicative of reductive evolution. This suggests that specialists are loosing genes required to live in alternative hosts or as saprophytes. Several components of mobile genetic elements were also highly divergent or lost in specialists. Exceptionally, the genome of the specialist strain ARSEF 443 contained extra insertion elements that might play a role in generating evolutionary novelty.
2009-06-25 | GSE14846 | GEO
Project description:Influence of JA/SA-deficient Arabidopsis on generalist and specialist aphids' plant-induced transcriptional plasticity
| PRJNA1194682 | ENA
Project description:Arabidopsis thaliana plants were infested i) with sucking insect herbivores (the generalist aphid Myzus persicae and the specialist aphid Brevicoryne brassicae), ii) with chewing insect herbivores (generalist caterpillars of Spodoptera exigua and specialist caterpillars of Pieris rapae) or iii) were treated by wounding. For each treatment, rosette leaves were harvested at two time points (6h and 24h) after removal of insects. For chewing herbivores and wounding both local, i.e. immediately damaged leaves, and systemic, i.e. undamaged leaves from the same plant, were collected. Control plants were uninfested, but otherwise equally treated and harvested in parallel. We tested the hypothesis that Arabidopsis can recognize and respond differentially to insect species at the transcriptional level using a genome wide microarray. Transcriptional reprogramming was characterized using co-expression analysis in damaged and undamaged leaves at two times in response to mechanical wounding and four insect species. In all, 2778 (10.6%) of annotated genes on the array were differentially expressed in at least one treatment. Responses differed mainly between aphid and caterpillar and sampling times. Responses to aphids and caterpillars shared only 10% of up-regulated and 8% of down-regulated genes. Responses to two caterpillars shared 21% and 12% of up- and down-regulated genes, whereas responses to the two aphids shared only 7% and 4% of up-regulated and down-regulated genes. Overlap in genes expressed between 6h and 24h was 3-15%, and depended on the insect species. Responses in attacked and unattacked leaves differed at 6h but converged by 24h. Genes responding to the insects are also responsive to many stressors and included primary metabolism. Aphids down-regulated amino acid catabolism; caterpillars stimulated production of amino acids involved in glucosinolate synthesis. Co-expression analysis revealed 17 response networks. Transcription factors were a major portion of differentially expressed genes throughout and responsive genes shared most of the known or postulated binding sites.
2015-10-05 | GSE62287 | GEO
Project description:Here we show that Drosophila sechelliaâa specialist on the fruit of Morinda citrifolia that recently diverged from its generalist sister-species, D. simulansâhas rapidly accumulated loss-of-function alleles and reduced gene expression at genes affecting olfaction, detoxification, and metabolism. While D. sechellia increases expression of genes involved with oogenesis and fatty acid metabolism when on its host, many more genes show reduced expression in D. sechellia. For several functionally related genes, this decrease in expression is associated with loss-of-function alleles. The rapid accumulation of these alleles potentially affected D. sechelliaâs initial adaptation to M. citrifolia, likely contributes to D. sechelliaâs poor competitive ability off of its host, and increases ecological isolation between D. sechellia and its sister species. Our results suggest that a subset of genes reduce or lose function as a consequence of host specialization, which may explain why, in general, specialist insects tend to shift to chemically similar hosts. Moreover, if the accumulation of non- or weakly functional genes in a specialist enhances the ecological isolation between it and other species, then this process may explain why specialists are speciose. Keywords: comparative hybridization, gene expression 2 species (simulans and sechella) by choice vs no-choice treatment for octanoic & hexanoic acid blend
2010-06-24 | E-GEOD-13789 | biostudies-arrayexpress
Project description:The entomopathogen Metarhizium anisopliae contains strains with wide host ranges and specialist strains adapted to particular hosts. Patterns of gene duplication, divergence and deletion in three generalist and three specialist strains were investigated by heterologous hybridization of genomic DNA to genes from the generalist strain ARSEF 2575. Many sequences from 2575 that are highly conserved in fungi showed rapid evolution and loss in specialist Metarhizium genomes. Some poorly hybridizing genes in specialists were functionally coordinated, including several involved in toxin biosyntheses and sugar metabolism in root exudates, indicative of reductive evolution. This suggests that specialists are loosing genes required to live in alternative hosts or as saprophytes. Several components of mobile genetic elements were also highly divergent or lost in specialists. Exceptionally, the genome of the specialist strain ARSEF 443 contained extra insertion elements that might play a role in generating evolutionary novelty. Three microarray slides were used in comparison (cDNAs are replicated in triplicate on each slide). 324 strainâ??s DNA was co-hybridized with strain ARSEF 2575 DNA in dye swapping replicate experiments and the relative hybridization efficiency (fluorescence ratio) of their DNA for strain ARSEF 2575 genes was compared. This array harbors PCR amplified fragments from the unique cDNA clones from M. anisopliae var. anisopliae ARSEF 2575 and a few genes from M. anisopliae var. acridum ARSEF 324 absent from the libraries of ARSEF 2575. In total, 1730 amplified clones were printed in triplicates on the slides. Additional background control was provided by 30 randomly distributed spots of 3Ã?SSC buffer. Printing, hybridization, and scanning of slides was as described before (Freimoser et al., 2005).
2010-05-16 | E-GEOD-14846 | biostudies-arrayexpress
Project description:Group A Streptococcus (GAS) has a rich evolutionary history of horizontal transfer among its core genes. Yet, despite extensive genetic mixing, GAS strains have discrete ecological phenotypes. To further our understanding of the molecular basis for ecological phenotypes, comparative genomic hybridization of a set of 97 diverse strains to a GAS pan-genome microarray was undertaken, and the association of accessory genes with emm genotypes that define tissue tropisms for infection was determined. Of the 22 non-prophage, accessory gene regions (AGRs) identified, only three AGRs account for all statistically significant linkage disequilibrium among strains having the genotypic biomarkers for throat versus skin infection specialist. Networked evolution and population structure analysis of loci representing each of the AGRs reveals that most strains with the skin specialist and generalist biomarkers form discrete clusters, whereas strains with the throat specialist biomarker are highly diverse. To identify co-inherited and co-selected accessory genes, the strength of genetic associations was determined for all possible pair wise combinations of accessory genes among the 97 GAS strains. Accessory genes showing very strong associations provide the basis for an evolutionary model, which reveals that a major transition between many throat and skin specialist haplotypes correlates with the gain or loss of genes encoding fibronectin-binding proteins. This study employs a novel synthesis of tools to help delineate the major genetic changes associated with key adaptive shifts in an extensively recombined bacterial species.
2011-10-03 | GSE31860 | GEO
Project description:Here we show that Drosophila sechellia—a specialist on the fruit of Morinda citrifolia that recently diverged from its generalist sister-species, D. simulans—has rapidly accumulated loss-of-function alleles and reduced gene expression at genes affecting olfaction, detoxification, and metabolism. While D. sechellia increases expression of genes involved with oogenesis and fatty acid metabolism when on its host, many more genes show reduced expression in D. sechellia. For several functionally related genes, this decrease in expression is associated with loss-of-function alleles. The rapid accumulation of these alleles potentially affected D. sechellia’s initial adaptation to M. citrifolia, likely contributes to D. sechellia’s poor competitive ability off of its host, and increases ecological isolation between D. sechellia and its sister species. Our results suggest that a subset of genes reduce or lose function as a consequence of host specialization, which may explain why, in general, specialist insects tend to shift to chemically similar hosts. Moreover, if the accumulation of non- or weakly functional genes in a specialist enhances the ecological isolation between it and other species, then this process may explain why specialists are speciose. Keywords: comparative hybridization, gene expression
2008-12-03 | GSE13789 | GEO
Project description:Here we show that Drosophila sechellia—a specialist on the fruit of Morinda citrifolia that recently diverged from its generalist sister-species, D. simulans—has rapidly accumulated loss-of-function alleles and reduced gene expression at genes affecting olfaction, detoxification, and metabolism. While D. sechellia increases expression of genes involved with oogenesis and fatty acid metabolism when on its host, many more genes show reduced expression in D. sechellia. For several functionally related genes, this decrease in expression is associated with loss-of-function alleles. The rapid accumulation of these alleles potentially affected D. sechellia’s initial adaptation to M. citrifolia, likely contributes to D. sechellia’s poor competitive ability off of its host, and increases ecological isolation between D. sechellia and its sister species. Our results suggest that a subset of genes reduce or lose function as a consequence of host specialization, which may explain why, in general, specialist insects tend to shift to chemically similar hosts. Moreover, if the accumulation of non- or weakly functional genes in a specialist enhances the ecological isolation between it and other species, then this process may explain why specialists are speciose. Keywords: comparative hybridization, gene expression
2008-12-03 | GSE13778 | GEO