Project description:This SuperSeries is composed of the following subset Series: GSE24446: Genetic abnormalities in GBM brain tumors GSE24452: Genetic abnormalities in various cell subpopulations of GBM brain tumors GSE24557: Exon-level expression profiles of GBM brain tumors Refer to individual Series
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.
Project description:To elucidate the epithelial cell diversity within the nasal inferior turbinates, a comprehensive investigation was conducted comparing control subjects to individuals with house dust mite-induced allergic rhinitis. This study aimed to delineate the differential expression profiles and phenotypic variations of epithelial cells in response to allergic rhinitis. This research elucidated distinct subpopulations and rare cell types of epithelial cells within the nasal turbinates, discerning alterations induced by allergic rhinitis. Furthermore, by interrogating transcriptomic signatures, the investigation provided novel insights into the cellular dynamics and immune responses underlying allergic rhinitis pathogenesis
Project description:In the current work, we present the first proteogenomic dataset of GBM clinical samples to date. We have assembled a cohort of 87 GBM patients of varying survival rates and performed MS-based proteomics analysis as well as RNA-seq in order to identify the molecular differences associated with survival and examine the contribution of each layer to GBM landscape. We show that each layer alone only partially reflects patient survival, but RNA-protein integration identifies clear patterns of layer-specific and layer-common processes specifically contributing to either short-term or long-term survival of patients. Furthermore, we compare our data to published single-cell RNA-seq of GBM tumors and evaluate the RNA-protein variability within single-cell based tumor subpopulations. We found that while all signatures of the four subpopulations tend to have high RNA-protein correlation, each signature is associated differently with survival. Altogether, these results highlight the potential of proteogenomics to further stratify heterogeneity in GBM tumors and identify processes contributing to poorer survival.
Project description:Glioblastoma multiforme (GBM) is a highly heterogeneous disease that shows an enourmous range of genetic abnormalities in comparison to other astrocytic tumors. Intra-patient heterogeneity in GBM has been poorly characterized both at phenotypic and genomic level. During surgical GBM resections, we have extracted between 4 and 8 tumor subsamples from different areas of the malignant tissue that were at least 1cm apart. Our aim to asses the intra-tumoral heterogeneity at the gene expression level to uncover important dynamics underlying GBM progression that may have relevant implication for treatment.