Project description:We have used a tiled microarray based on the D4Z4 sequence, and hybridized amplified transcripts from facioscapulohumeral muscular dystrophy (FSHD) and control (CTRL) samples to detect D4Z4 related expression.
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:The prevailing patho-mechanistic paradigm for myotonic dystrophy (DM) is that the aberrant presence of embryonic isoforms is responsible for many, if not most, aspects of the pleiotropic disease phenotype. In order to identify such aberrantly expressed isoforms in skeletal muscle of DM type 1 (DM1) and type 2 (DM2) patients, we utilized the Affymetrix exon array to characterize the largest collection of DM samples analyzed to date, and included non-DM dystrophic muscle samples (NMD) as disease controls. For the exon array profiling on the Human Exon 1.0 ST array (Affymetrix Santa Clara, CA) we used a panel of 28 skeletal muscle biopsies from DM1 (n=8), DM2 (n=10), Becker muscular dystrophy, BMD, (n=3), Duchenne muscular dystrophy, DMD (n=1), Tibial muscular dystrophy, TMD, (n=2) and normal skeletal muscle (n=4). Normal control RNAs were purchased commercially. .CEL files were generated with a pre-commercial version of the Affymetrix processing software, and the headers might be non-standard. In our lab, users of the Partek software could use them, whereas users of GeneSpring had to modify the header information.
Project description:Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant disorder linked to contractions of the D4Z4 repeat array in the subtelomeric region of chromosome 4q. By comparing genome-wide gene expression data from muscle biopsies of patients with FSHD to those of 11 other neuromuscular disorders, we intend to identify disease-specific changes which are more likely to be involved in the early stages of the disease progression. The data will help to identify pathological mechanisms involved in FSHD. Experiment Overall Design: Comparison of the profiles of FSHD to 13 other conditions for disease-specific changes. The 13 conditions are NHM (Normal healthy muscle) n=15; JDM (Juvenile dermatomyositis) n=25; HSP (Human spastic paraplegia) n=4; FSHD (facioscapulohumeral dystrophy) unaffected n=5, affected n=9; FKRP (Fukutin related protein deficiency) n=7; ED-L (Emery-Dreifuss muscular dystrophy, lamin A/C deficiency) n=4; ED-E (Emery-Dreifuss muscular dystrophy, emerin deficiency) n=4; DYSF (dysferlinopathy) n=10; DMD (Duchenne Muscular Dystrophy) n=10; CALP (Calpain-3 deficiency) n=10; BMD (Becker Muscular Dystrophy) n=5; AQM (Acute quadriplegic myopathy) n=5; ALS (Amyotrophic lateral sclerosis) n=9.