Project description:We present the de novo transcriptome sequencing, analysis and microarray development for a vertebrate herbivore, the woodrat (Neotoma spp.). This genus is of ecological and evolutionary interest, especially with respect to ingestion and hepatic metabolism of potentially toxic plant secondary compounds. We generated a liver transcriptome of the desert woodrat (Neotoma lepida) with the Roche 454 platform. The assembled contigs were well annotated using rodent references (99.7% annotation), and biotransformation function was reflected in the gene ontology. The transcriptome was used to develop a custom microarray (eArray, Agilent). To compare the effect of native diet/habitat and phylogenetic similarity, we performed 3 experiments with the Neotoma probes only: one across species with similar habitat niches (N. lepida versus N. bryanti, Palm Springs), one across species with different habitat niches (N. lepida versus N. bryanti, Caspers Wilderness), and one across populations within a species (N. bryant Palm Springs versus Caspers Wilderness). The resulting one-color arrays had high technical and biological quality. Probes designed from the woodrat transcriptome performed significantly better than functionally similar probes from the Norway rat (Rattus norvegicus). Biotransformation processes and functions were highly represented in the results. Comparisons between ecologically similar woodrat species revealed fewer gene expression differences than ecologically different woodrat species. The conspecific comparison had overall fewest differences. Gene expression was compared across 3 groups of woodrats: Neotoma lepida (n=4), N. bryanti Palm Springs (n=4), and N. bryanti Caspers Wilderness (n=4). Animals were fed a rabbit chow diet, called control; intake was monitored over 10 days, after which RNA was extracted from hepatic tissue. One-color arrays were performed.
Project description:To understand the ecophysiology of Sulfurihydrogenibium spp. in situ, integrated metagenomic, metatranscriptomic and metaproteomic analyses were conducted on a microbial community from Narrow Gauge at Mammoth Hot Springs, Yellowstone National Park.
Project description:We present the de novo transcriptome sequencing, analysis and microarray development for a vertebrate herbivore, the woodrat (Neotoma spp.). This genus is of ecological and evolutionary interest, especially with respect to ingestion and hepatic metabolism of potentially toxic plant secondary compounds. We generated a liver transcriptome of the desert woodrat (Neotoma lepida) with the Roche 454 platform. The assembled contigs were well annotated using rodent references (99.7% annotation), and biotransformation function was reflected in the gene ontology. The transcriptome was used to develop a custom microarray (eArray, Agilent). To compare the effect of native diet/habitat and phylogenetic similarity, we performed 3 experiments with the Neotoma probes only: one across species with similar habitat niches (N. lepida versus N. bryanti, Palm Springs), one across species with different habitat niches (N. lepida versus N. bryanti, Caspers Wilderness), and one across populations within a species (N. bryant Palm Springs versus Caspers Wilderness). The resulting one-color arrays had high technical and biological quality. Probes designed from the woodrat transcriptome performed significantly better than functionally similar probes from the Norway rat (Rattus norvegicus). Biotransformation processes and functions were highly represented in the results. Comparisons between ecologically similar woodrat species revealed fewer gene expression differences than ecologically different woodrat species. The conspecific comparison had overall fewest differences.
Project description:Within the human gut reside diverse microbes coexisting with the host in a mutually advantageous relationship. We comprehensively identified the modulatory effects of phylogenetically diverse human gut microbes on the murine intestinal transcriptome. Gene-expression profiles were generated from the whole-tissue intestinal RNA of mice colonized with various single microbial strains. The selection of microbe-specific effects, from the transcriptional response, yielded only a small number of transcripts, indicating that symbiotic microbes have only limited effects on the gut transcriptome overall. Moreover, none of these microbe-specific transcripts was uniformly induced by all microbes. Interestingly, these responsive transcripts were induced by some microbes but repressed by others, suggesting different microbes can have diametrically opposed consequences.
Project description:Microbes are an integral component of the tumor microenvironment (TME). However, mechanisms that direct microbial recruitment into tumors and the spatial relationship between intratumoral microbes and host cells remain poorly understood. Here, we show that microbes and immune cells have parallel spatial distribution and that the presence of intratumoral microbes is dependent on T cells. Analysis of human pancreatic ductal adenocarcinomas (PDAC) and lung adenocarcinomas (LUAD) revealed a spatially heterogeneous distribution of lipopolysaccharide (LPS) that is associated with T cell infiltration. Using mouse models of PDAC, we found that microbes were more abundant and diverse in tumors that were enriched in T cells compared to tumors that lacked T cells, despite no significant differences in the fecal microbiome. Consistent with these findings, we detected elevated levels of microbial genes in T cell-enriched tumor nests in human PDAC. Compared to microbe-poor tumor nests, microbe-enriched tumor nests displayed a higher number of myeloid cells, B cells, and plasma cells. Microbe-enriched tumor nests also showed upregulation of immune-related processes, including responses to bacteria, and receptors that mediate mucosal immune responses to microbes. Administration of antibiotics to tumor-bearing mice altered the phenotype and presence of intratumoral myeloid cells and B cells but did not alter T cell infiltration. In contrast, depletion of T cells reduced the presence of intratumoral microbes. Our results identify a novel coupling between microbes and the intratumoral immune landscape, with T cells shaping microbial presence and subsequent microbial-host interactions.