Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.6.1 (sulfatase)
 3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mucolipidosis III (ML-III), or pseudo-Hurler polydystrophy, is an autosomal recessive Hurler-like disorder without mucopolysacchariduria. The diagnosis is challenging for rheumatologists since the musculoskeletal presentation is similar to some rheumatic diseases. We report a case of ML-III in a 16-year-old Taiwanese boy. The characteristic findings of sonography and magnetic resonance imaging (MRI) of claw hand deformity are described. A 16-year-old boy was referred to our rheumatologic clinic because of progressive claw hand deformity, multiple joint stiffness and tightness of the skin over the fingers at the age of 6 years. Sonography and MRI examination disclosed tendon sheath thickening over extensor tendons of both wrists and fingers without features of active inflammation over tendons or joints nor thickening of skin. Urinary glycosaminoglycans were normal. The diagnosis of ML-III was confirmed by the presence of elevated activities of beta-glucuronidase (2141.99 nmol/mg protein/hour), arylsulfatase A (1237.7 nmol/mg protein/hour) and alpha-fucosidase (52.95 nmol/mg protein/hour) in his plasma and decreased activity of these lysosomal enzymes in cultured skin fibroblasts. Sonography and MRI screening for claw hand deformity may offer important clues enabling early diagnosis of ML-III.
 ...
PMID:A mucolipidosis III patient presenting characteristic sonographic and magnetic resonance imaging findings of claw hand deformity. 1536 46

Multiple sulfatase deficiency (MSD), mucolipidosis (ML) II/III and Niemann-Pick type C1 (NPC1) disease are rare but fatal lysosomal storage disorders caused by the genetic defect of non-lysosomal proteins. The NPC1 protein mainly localizes to late endosomes and is essential for cholesterol redistribution from endocytosed LDL to cellular membranes. NPC1 deficiency leads to lysosomal accumulation of a broad range of lipids. The precise functional mechanism of this membrane protein, however, remains puzzling. ML II, also termed I cell disease, and the less severe ML III result from deficiencies of the Golgi enzyme N-acetylglucosamine 1-phosphotransferase leading to a global defect of lysosome biogenesis. In patient cells, newly synthesized lysosomal proteins are not equipped with the critical lysosomal trafficking marker mannose 6-phosphate, thus escaping from lysosomal sorting at the trans Golgi network. MSD affects the entire sulfatase family, at least seven members of which are lysosomal enzymes that are specifically involved in the degradation of sulfated glycosaminoglycans, sulfolipids or other sulfated molecules. The combined deficiencies of all sulfatases result from a defective post-translational modification by the ER-localized formylglycine-generating enzyme (FGE), which oxidizes a specific cysteine residue to formylglycine, the catalytic residue enabling a unique mechanism of sulfate ester hydrolysis. This review gives an update on the molecular bases of these enigmatic diseases, which have been challenging researchers since many decades and so far led to a number of surprising findings that give deeper insight into both the cell biology and the pathobiochemistry underlying these complex disorders. In case of MSD, considerable progress has been made in recent years towards an understanding of disease-causing FGE mutations. First approaches to link molecular parameters with clinical manifestation have been described and even therapeutical options have been addressed. Further, the discovery of FGE as an essential sulfatase activating enzyme has considerable impact on enzyme replacement or gene therapy of lysosomal storage disorders caused by single sulfatase deficiencies.
 ...
PMID:Molecular basis of multiple sulfatase deficiency, mucolipidosis II/III and Niemann-Pick C1 disease - Lysosomal storage disorders caused by defects of non-lysosomal proteins. 1912 46

Newly synthesized soluble lysosomal hydrolases require mannose 6-phosphate (Man6P) residues on their oligosaccharides for their transport to lysosomes. The formation of Man6P residues is catalyzed by the GlcNAc-1-phosphotransferase, which is defective in the lysosomal storage disorders mucolipidosis type II (ML II) and ML III. Both hypersecretion and reduced intracellular level of lysosomal enzymes as well as direct sequencing of GlcNAc-1-phosphotransferase genes are important diagnostic markers for ML II and ML III. A high-affinity Man6P-specific single-chain antibody fragment was generated, allowing the rapid indirect demonstration of defective GlcNAc-1-phosphotransferase. In media and extracts of cultured fibroblasts of healthy controls but not of ML II and ML III patients, several Man6P-containing proteins could be detected by anti-Man6P Western blotting. Immunoprecipitation of Man6P-containing proteins from conditioned media or mouse brain extracts followed by arylsulfatase A and cathepsin D Western blotting confirmed the specificity of the antibody fragment for lysosomal proteins. Application of the antibody fragment in immunohistochemistry of human brain slices from nonaffected patients showed strong neuronal immunoreactivity, which was not observed in cortical sections of an ML II patient. Finally, in brain extracts of a novel GlcNAc-1-phosphotransferase knock-in mouse no Man6P-containing proteins were detectable. Thus, the single-chain antibody fragment against Man6P was demonstrated to allow the specific, rapid, and convenient detection of Man6P-containing proteins and facilitates the diagnosis of ML II and ML III.
 ...
PMID:A novel single-chain antibody fragment for detection of mannose 6-phosphate-containing proteins: application in mucolipidosis type II patients and mice. 2047 86