Project description:Energy metabolism and extracellular matrix function are closely connected to orchestrate and maintain tissue organization, but the crosstalk is poorly understood. Here, we used scRNA-seq analysis to uncover the importance of respiration for extracellular matrix homeostasis in mature cartilage. Genetic inhibition of respiration in cartilage results in the expansion of a central area of 1-month-old mouse femur head cartilage showing disorganized chondrocytes and increased deposition of extracellular matrix material. scRNA-seq analysis identified a cluster-specific decrease in mitochondrial DNA-encoded respiratory chain genes and a unique regulation of extracellular matrix-related genes in nonarticular chondrocyte clusters. These changes were associated with alterations in extracellular matrix composition, a shift in the collagen/non-collagen protein content and an increase of collagen crosslinking and ECM stiffness. The results demonstrate, based on findings of the scRNA-seq analysis, that respiration is a key factor contributing to ECM integrity and mechanostability in cartilage and presumably also in many other tissues.
Project description:Autosomal Recessive Spastic Ataxia of Charlevoix-Saguenay (ARSACS) is caused by mutations in SACS gene encoding sacsin. ARSACS patients and mouse models display early degeneration of cerebellum in agreement with high sacsin expression in this organ. We performed unbiased transcriptomic of cerebella from Sacs KO mice versus controls to dissect the mechanisms underlying cerebellar degeneration in ARSACS.
Project description:BackgroundUlcerative colitis is a chronic inflammatory disease affecting the colon. During chronic inflammation of epithelial cells, lipid metabolism via pro-inflammatory eicosanoids is known to modify the immune response.MethodsStarting from the Mammalian Metabolic Database, the expression of metabolic enzymes was investigated in two independent cohorts from transcriptome datasets GSE38713 and GSE11223, which analyzed ulcerative colitis tissue samples from the digestive tract.ResultsIn the first cohort, 145 differentially expressed enzymes were identified as significantly regulated between ulcerative colitis tissues and normal controls. Overexpressed enzymes were selected to tune an Elastic Net model in the second cohort. Using the best parameters, the model achieved a prediction accuracy for ulcerative colitis with an area under the curve (AUC) of 0.79. Twenty-two metabolic enzymes were found to be commonly overexpressed in both independent cohorts, with decreasing Elastic Net predictive coefficients as follows: LIPG (3.98), PSAT1 (3.69), PGM3 (2.74), CD38 (2.28), BLVRA (1.99), CBR3 (1.94), NT5DC2 (1.76), PHGDH (1.71), GPX7 (1.58), CASP1 (1.56), ASRGL1 (1.4), SOD3 (1.25), CHST2 (0.965), CHST11 (0.95), KYNU (0.94), PLAG2G7 (0.92), SRM (0.87), PTGS2 (0.80), LPIN1 (0.47), ME1 (0.31), PTGDS (0.14), and ADA (0.13). Functional enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database highlighted the main implications of these enzymes in cysteine and methionine metabolism (adjusted p-value = 0.01), arachidonic acid and prostaglandin metabolism (adjusted p-value = 0.01), and carbon metabolism (adjusted p-value = 0.04). A metabolic score based on the transcriptional activation of the validated twenty-two enzymes was found to be significantly greater in Ulcerative colitis samples compared to healthy donor samples (p-value = 1.52 × 10-8).ConclusionsA metabolic expression score was established and reflects the implications of heterogeneous metabolic pathway deregulations in the digestive tract of patients with ulcerative colitis.
Project description:With improved whole-cell isolation protocols, we performed single-cell RNA sequencing (scRNA-seq) and profiled the transcriptomes from adult non-human primate brain. We identified discriminative cell populations with canonical and novel markers. Cross-species projection demonstrated the evolutionary conservation among mouse, monkey, and human. This dataset serves as a detailed transcriptomic atlas for understanding the adult primate central nervous system.
Project description:Yolk sac is an important site for early embryonic hematopoiesis. However, our understanding of early hematopoietic development is still very limited. Single cell transcriptome sequencing provides us with a good research method. Here, we performed single cell RNA-seq analysis for Carnegie stage 11 (CS11) and Carnegie stage 15 (CS15) human yolk sacs.
Project description:Here, we used single cell RNA-sequencing (scRNA-seq) to profile pluripotent stem cell derived human intestinal organoids (HIOs) grown in matrigel or a non-adhesive alginate hydrogel after 28 days of in vitro growth. Additionally, we used scRNA-seq to profile HIOs derived in the presence of Neuregulin 1 (NRG1) and/or EGF after 40 days of in vitro growth.