Project description:Huanglongbing (HLB) is a worldwide devastating disease of citrus. There are no effective control measures for this newly emerging but century-old disease. A powerful oligonucleotide microarray of high-density 16S rRNA genes, the PhyloChip microarray, has been developed and effectively used to study bacterial diversity, especially from environmental samples. In this article, we aim to decipher the bacterial microbiome in HLB-affected citrus versus non-infected citrus as well as in citrus plants treated with ampicillin and gentamicin using PhyloChip-based metagenomics.
Project description:Cruciferous vegetables and their derived compounds, such as glucosinolates, have demonstrated anti-inflammatory properties in animal models. In this study, broccoli-supplemented diet induced changes in the gut microbiome and its role in host and bacterial gene expression were examined in mice following consumption of the Total Western Diet (TWD), which is based on NHANES data and represents the composition of a typical American diet. C57BL/6 male mice were fed a TWD for six weeks followed by a supplementation of 0, 0.5, 1 or 2.5% broccoli powder for three weeks. Microbial communities from cecal contents were taxonomically profiled using 16S and metagenomics sequencing, and metatranscriptomics was used to assess functionality of bacterial species. Cecum tissues were also analyzed for host transcriptomics.
Project description:Cruciferous vegetables and their derived compounds, such as glucosinolates, have demonstrated anti-inflammatory properties in animal models. In this study, broccoli-supplemented diet induced changes in the gut microbiome and its role in host and bacterial gene expression were examined in mice following consumption of the Total Western Diet (TWD), which is based on NHANES data and represents the composition of a typical American diet. C57BL/6 male mice were fed a TWD for six weeks followed by a supplementation of 0, 0.5, 1 or 2.5% broccoli powder for three weeks. Microbial communities from cecal contents were taxonomically profiled using 16S and metagenomics sequencing, and metatranscriptomics was used to assess functionality of bacterial species. Cecum tissues were also analyzed for host transcriptomics.
Project description:Plant pathogens can cause serious diseases that impact global agriculture1. Understanding how the plant immune system naturally restricts pathogen infection holds a key to sustainable disease control in modern agricultural practices. However, despite extensive studies into the molecular and genetic basis of plant defense against pathogens since the 1950s2,3, one of the most fundamental questions in plant pathology remains unanswered: how resistant plants halt pathogen growth during immune activation. In the case of bacterial infections, a major bottleneck is an inability to determine the global bacterial transcriptome and metabolic responses in planta. Here, we developed an innovative pipeline that allows for in planta high-resolution bacterial transcriptome analysis with RNA-Seq, using the model plant Arabidopsis thaliana and the foliar bacterial pathogen Pseudomonas syringae. We examined a total of 27 combinations of plant immunity and bacterial virulence mutants to gain an unprecedented insight into the bacterial transcriptomic responses during plant immunity. We were able to identify specific bacterial transcriptomic signatures that are linked to bacterial inhibition during two major forms of plant immunity: pattern-triggered immunity and effector-triggered immunity. Among them, regulation of a P. syringae sigma factor gene, involved in iron regulation and an unknown process(es), was found to play a causative role in bacterial restriction during plant immunity. This study unlocked the enigmatic mechanisms of bacterial growth inhibition during plant immunity; results have broad basic and practical implications for future study of plant diseases.
Project description:Plant pathogens can cause serious diseases that impact global agriculture1. Understanding how the plant immune system naturally restricts pathogen infection holds a key to sustainable disease control in modern agricultural practices. However, despite extensive studies into the molecular and genetic basis of plant defense against pathogens since the 1950s2,3, one of the most fundamental questions in plant pathology remains unanswered: how resistant plants halt pathogen growth during immune activation. In the case of bacterial infections, a major bottleneck is an inability to determine the global bacterial transcriptome and metabolic responses in planta. Here, we developed an innovative pipeline that allows for in planta high-resolution bacterial transcriptome analysis with RNA-Seq, using the model plant Arabidopsis thaliana and the foliar bacterial pathogen Pseudomonas syringae. We examined a total of 27 combinations of plant immunity and bacterial virulence mutants to gain an unprecedented insight into the bacterial transcriptomic responses during plant immunity. We were able to identify specific bacterial transcriptomic signatures that are linked to bacterial inhibition during two major forms of plant immunity: pattern-triggered immunity and effector-triggered immunity. Among them, regulation of a P. syringae sigma factor gene, involved in iron regulation and an unknown process(es), was found to play a causative role in bacterial restriction during plant immunity. This study unlocked the enigmatic mechanisms of bacterial growth inhibition during plant immunity; results have broad basic and practical implications for future study of plant diseases.