Project description:Upon exposure to unfavorable environmental conditions, plants need to respond quickly to maintain their homeostasis. For instance, physiological, biochemical and transcriptional changes occur during plant-pathogen interaction. In the case of Vanilla planifolia Jacks., a worldwide economically important crop, it is susceptible to Fusarium oxysporum f. sp. vanillae. This pathogen causes root and stem rot in vanilla plants that lead to plant death. To investigate how vanilla plants, respond at the transcriptional level upon infection with F. oxysporum f. sp. vanillae, here we employed the RNA-Seq approach to analyze the dynamics of whole-transcriptome changes during two-time frames of the infection. Analysis of global gene expression profiles indicated that the major transcriptional change occurred at 2 dpi, in comparison to 10 dpi. Whereas 3420 genes were found with a differential expression at 2 dpi, only 839 were identified at 10 dpi. The analysis of the transcriptional profile at 2 dpi suggests that, among other responses, vanilla plants prepare to counter the infection by gathering a pool of translational regulation-related transcripts. The screening of transcriptional changes of V. planifolia Jacks upon infection by F. oxysporum f. sp. vanillae provides insights into the plant molecular response, particularly the upregulation of ribosomal proteins at early stages. Thus, we propose that the plant-pathogen interaction between V. planifolia Jacks and F. oxysporum f. sp. vanillae causes a transcriptional reprogramming coupled with a translational regulation. Altogether, this study provides the identification of molecular players that could help to fight the most damaging disease of vanilla.
Project description:We performed RNA-Seq based gene expression analysis of Arabidopsis Col-0 plants grown in presence of SynComCol-0 (eubiotic bacterial community), SynCommfec (dysbiotic bacterial community) and Axenic conditions in GnotoPot plant gnotobiotic growth system. SynCom preparation was done by mixing equal ratio of the each strain measured based on optical density of (OD600) in 10 mM MgCl2 and adjusting to the final combined OD600 of 0.04. Plants were grow in GnotoPots as described in (Chen et al, Nature 2020). We identified genes differentially enriched in response to presence of eubiotic and dysbiotic bacterial communities. Our results suggested that in presence of dysbiotic community there is over abundance of gene expression for immunity/defense-related genes in SynCommfec compared SynComCol-0 colonized plants.
Project description:Here we have compared adult wildtype (N2) C. elegans gene expression when grown on different bacterial environments/fod sources in an effort to model naturally occuring nematode-bacteria interactions at the Konza Prairie. We hypothesize that human-induced changes to natural environments, such as the addition of nitrogen fertalizer, have effects on the bacterial community in soils and this drives downstream changes in the structure on soil bacterial-feeding nematode community structure. Here we have used transcriptional profiling to identify candidate genes involved in the interaction of nematodes and bacteria in nature.
Project description:Origanum oil (ORO), garlic oil (GAO), and peppermint oil (PEO) were shown to effectively lower methane production, decrease abundance of methanogens, and change abundances of several bacterial populations important to feed digestion in vitro. In this study, the impact of these essential oils (EOs, at 0.50 g/L), on the rumen bacterial community composition was further examined using the recently developed RumenBactArray.
Project description:Total bacterial DNA was isolated from water and sediment samples from a local watershed and 16S rRNA sequences were analyzed using the Illumina MiSeq v3 platform in order to generate snapshots of bacterial community profiles.
Project description:Understanding the bacterial community structure, and their functional analysis for active bioremediation process is essential to design better and cost effective strategies. Microarray analysis enables us to simultaneously study the functional and phylogenetic markers of hundreds of microorganisms which are involved in active bioremediation process in an environment. We have previously described development of a hybrid 60-mer multibacterial microarray platform (BiodegPhyloChip) for profiling the bacterial communities and functional genes simultaneously in environments undergoing active bioremediation process (Pathak et al; Appl Microbiol Biotechnol,Vol. 90, 1739-1754). The present study involved profiling the status of bacterial communities and functional (biodegradation) genes using the developed 60-mer oligonucleotide microarray BiodegPhyloChip at five contaminated hotspots in the state of Gujarat, in western India. The expression pattern of functional genes (coding for key enzymes in active bioremediation process) at these sites was studied to understand the dynamics of biodegradation in the presence of diverse group of chemicals. The results indicated that the nature of pollutants and their abundance greatly influence the structure of bacterial communities and the extent of expression of genes involved in various biodegradation pathways. In addition, site specific factors also play a pivotal role to affect the microbial community structure as was evident from results of 16S rRNA gene profiling of the five contaminated sites, where the community structure varied from one site to another drastically.
Project description:To determine whether and how warming affects the functional capacities of the active microbial communities, GeoChip 5.0 microarray was used. Briefly, four fractions of each 13C-straw sample were selected and regarded as representative for the active bacterial community if 16S rRNA genes of the corresponding 12C-straw samples at the same density fraction were close to zero.
Project description:The gut microbiome is significantly altered in inflammatory bowel diseases, but the basis of these changes is not well understood. We have combined metagenomic and metatranscriptomic profiling of the gut microbiome to assess changes to both bacterial community structure and transcriptional activity in a mouse model of colitis. Gene families involved in microbial resistance to oxidative stress, including Dps/ferritin, Fe-dependent peroxidase and glutathione S-transferase, were transcriptionally up-regulated in colitis, implicating a role for increased oxygen tension in gut microbiota modulation. Transcriptional profiling of the host gut tissue and host RNA in the gut lumen revealed a marked increase in the transcription of genes with an activated macrophage and granulocyte signature, suggesting the involvement of these cell types in influencing microbial gene expression. Down-regulation of host glycosylation genes further supports a role for inflammation-driven changes to the gut niche that may impact the microbiome. We propose that members of the bacterial community react to inflammation-associated increased oxygen tension by inducing genes involved in oxidative stress resistance. Furthermore, correlated transcriptional responses between host glycosylation and bacterial glycan utilisation support a role for altered usage of host-derived carbohydrates in colitis. Complementary transcription profiling data from the mouse hosts have also been deposited at ArrayExpress under accession number E-MTAB-3590 ( http://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-3590/ ).