Project description:To determine the effect of prohibitin overexpression on global gene expression in Caco2-BBE intestinal epithelial cells. 4 individual wells of Caco2-BBE cells, passage 41, were transfected with either empty vector (pcDNA4) or prohibitin/pcDNA4 for 72 hours. Total RNA isolated from 4 wells of cells/per treatment were pooled together for labeling and hybridization purposes.
Project description:Comparison of Campylobacter proteome in MH media with and without deoxycholic acid, in presence of FBS or after being exposed to INT 407 and Caco2 intestinal epithelial cells.
Project description:Organoids are a valuable 3D model to study the differentiated functions of the human intestinal epithelium. They are a particularly powerful tool to measure epithelial transport processs in health and disease. Though biological assays such as organoid swelling and intraluminal pH measurements are well established, their underlying functional genomics are not well characterized. Here we combine genome-wide analysis of open chromatin by ATAC-seq with transcriptome mapping by RNA-seq to define the genomic signature of human intestinal organoids (HIOs). These data provide an important tool for investigating key physiological and biochemical processes in the intestinal epithelium. We next compared the transcriptome and open chromatin profiles of HIOs with equivalent datasets from the Caco2 colorectal carcinoma line, which is an important 2D model of the intestinal epithelium. Our results define common features of the intestinal epithelium in HIO and Caco2 and further illustrate the cancer-associated program of the cell line. Generation of Caco2 organoids enabled interrogation of the molecular divergence of the 2D and 3D cultures. Over-represented motif analysis of open chromatin peaks identified Caudal Type Homeobox 2 (CDX2) as a key activating transcription factor in HIO, but not in monolayer cultures of Caco2. However, the CDX2 motif becomes overrepresented in open chromatin from Caco2 organoids, reinforcing the importance of this factor in intestinal epithelial differentiation and function. Intersection of the HIO and Caco2 transcriptomes further showed functional overlap in pathways of ion transport and tight junction integrity among others. These data make an important contribution to understanding human intestinal organoid biology.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.