Project description:The aim of the study was to identify significant alterations in genes and molecular functional pathways in comparison with normal and ACM tissue, and detect the marker genes to differentiate the different stage astrocytomas Total RNA was isolated from Seventeen tumor tissue of patients, which included two WHO grade I(T1) and five WHO grade II(T2), III(T3) and IV(T4) samples, and four pooled normal tissue samples. The genome-wide expression analysis was first performed by directly comparing the expression profile of highly enriched different grade astrocytomas and pooled normal tissues, we then applied various data-mining methods to process the 15 different grades tumor tissues sample. Paired T-test and Q-cluster method was performed to explore mark genes validated by qRT-PCR. This study utilized a pathway-specific enrichment analysis of the microarray data and quantified the gene expression difference between astrocytomas tumor and pooled normal tissues. BioCarta and KEGG pathways of the ACM compared to normal tissue were identified through enrichment tests on gene lists obtained using SAM, while GO is organized into hierarchical annotations in the context of normal cellular function, the BioCarta and KEGG database organizes the genes(gen products) into pathway reaction maps and functional complexes, including some disease-specific pathway
Project description:The aim of the study was to identify significant alterations in genes and molecular functional pathways in comparison with normal and ACM tissue, and detect the marker genes to differentiate the different stage astrocytomas
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.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.