Project description:Gut microbiome research is rapidly moving towards the functional characterization of the microbiota by means of shotgun meta-omics. Here, we selected a cohort of healthy subjects from an indigenous and monitored Sardinian population to analyze their gut microbiota using both shotgun metagenomics and shotgun metaproteomics. We found a considerable divergence between genetic potential and functional activity of the human healthy gut microbiota, in spite of a quite comparable taxonomic structure revealed by the two approaches. Investigation of inter-individual variability of taxonomic features revealed Bacteroides and Akkermansia as remarkably conserved and variable in abundance within the population, respectively. Firmicutes-driven butyrogenesis (mainly due to Faecalibacterium spp.) was shown to be the functional activity with the higher expression rate and the lower inter-individual variability in the study cohort, highlighting the key importance of the biosynthesis of this microbial by-product for the gut homeostasis. The taxon-specific contribution to functional activities and metabolic tasks was also examined, giving insights into the peculiar role of several gut microbiota members in carbohydrate metabolism (including polysaccharide degradation, glycan transport, glycolysis and short-chain fatty acid production). In conclusion, our results provide useful indications regarding the main functions actively exerted by the gut microbiota members of a healthy human cohort, and support metaproteomics as a valuable approach to investigate the functional role of the gut microbiota in health and disease.
Project description:Gastric ulcer, which affect many of patients and is deeply related with gastric cancer, is caused by chronic gastric acid stimulation. Stomach fundus, the main body of stomach, is a major source of gastric acid and peptidase for food digestion. Recapturing the main body of stomach requires mainly 3 functionally differentiated cells; parietal (oxyntic) cells, chief (zymogenic) cells, and surface mucous foveolar (pit) cells. We have previously shown the induction of stomach tissue with functional secreting activities by directed differentiation of mouse embryonic stem cells (ES cells) to stomach primordium with both gut epithelium and splanchnic mesoderm. However, generating human stomach with fundus and such functions has been elucidated and a long-desired goal. Here, we describe the method for establishing human embryonic stem cell-derived stomach organoids with fundus gland structure. Along with mouse stomach development and de novo stomach generation from mouse ES cells in vitro, we observed gut-like structure formation from human embryonic stem cells by induction of both endoderm and mesoderm. These human embryonic gut could differentiate into stomach primordium by growth factor stimulation as well as stomach development, and form stomach tissue in three-dimensional organoid culture. Furthermore, these stomach organoids contain fundus-like gland with parietal cells and chief cells, some of secreting activities, and is transcriptionally close to human stomach. Human functional stomach derived from embryonic stem cells represent powerful tools for analying human stomach development, and gastric ulcer related disease including gastric tumorgenesis.
Project description:Hippo-YAP signaling plays important roles in gut development and homeostasis. In this study, we use RNAseq to analyze the gene expression profiles of wild type stomach and YAP5SA-expressing stomach at E13.5. The goal of this study is to understand the transcription program regulated by YAP in the developing gut.
Project description:The main goal of the project is the study the associations between the gut metagenome and human health. The dataset contains data for n=7211 FINRISK 2002 participants who underwent fecal sampling. Demultiplexed shallow shotgun metagenomic sequences were quality filtered and adapter trimmed using Atropos (Didion et al., 2017), and human filtered using Bowtie2 (Langmead and Salzberg, 2012).