Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A first Japanese case of an adult polysaccharide storage myopathy (APSM) was reported. A 30-year-old Japanese male was admitted because of weakness of the lower limbs. The onset of the symptoms was at the age of 23. Neurologically he had moderate weakness of proximal limb muscles involving the lower limbs more than the upper and slightly decreased vibratory sense in the feet. His gait was waddling. The following laboratory values were obtained; SGOT 45 I.U., SGPT 83 I.U., CPK 218 I.U., UA 8.3 mg/dl. Ischemic exercise test of the forearm showed a normal rise of venous lactate. EMG revealed a mixture of myopathic and mild neurogenic patterns characterized by motor units of short duration and low amplitude with intermittent high amplitude potentials, fibrillation and fasciculation. There were also prominent myotonic discharges without clinical myotonia. MCV was normal, however sural nerve SCV was slightly slow (lt. 36/m, rt. 38 m/s). Muscle biopsy revealed vacuolar myopathy. Most vacuoles contained basophilic, PAS-positive, diastase-resistant and Lugol's iodine-negative material. With ATPase staining there was type 1 fiber predominance (84%), but the vacuoles were predominantly seen in type 2A fiber. In ultrastructural study, the storage material was located under the sarcolemma and in the areas of the intermyofibrillar network. No delimiting membranes were seen. At higher magnification, these masses were consisted of filaments. Therefore the storage material was considered to be unusual polysaccharide. Glycogen storage disease was suspected, however, biochemical study of the muscle specimen disclosed no enzymatic defect including branching enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Adult polysaccharide storage myopathy]. 269 Nov 65

Axon guidance (pathfinding) wires the brain during development and is regulated by various attractive and repulsive cues. Semaphorin 3A (Sema3A) is a repulsive cue, inducing the collapse of axon growth cones. In the mammalian forebrain, the corpus callosum is the major commissure that transmits information flow between the two hemispheres, and contralateral axons assemble into well-defined tracts. We found that the patterning of callosal axon projections in rodent layer II and III (L2/3) cortical neurons in response to Sema3A was mediated by the activation of Rab5, a small guanosine triphosphatase (GTPase) that mediates endocytosis, through the membrane fusion protein Rabaptin-5 and the Rab5 guanine nucleotide exchange factor (GEF) Rabex-5. Rabaptin-5 bound directly to Plexin-A1 in the Sema3A receptor complex [an obligate heterodimer formed by Plexin-A1 and neuropilin 1 (NP1)]; Sema3A enhanced this interaction in cultured neurons. Rabaptin-5 bridged the interaction between Rab5 and Plexin-A1. Sema3A stimulated endocytosis from the cell surface of callosal axon growth cones. In utero electroporation to reduce Rab5 or Rabaptin-5 impaired axon fasciculation or caused mistargeting of L2/3 callosal projections in rats. Overexpression of Rabaptin-5 or Rab5 rescued the defective callosal axon fasciculation or mistargeting of callosal axons caused by the loss of Sema3A-Plexin-A1 signaling in rats expressing dominant-negative Plexin-A1 or in NP1-deficient mice. Thus, our findings suggest that Rab5, its effector Rabaptin-5, and its regulator Rabex-5 mediate Sema3A-induced axon guidance during brain development.
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PMID:Semaphorin 3A activates the guanosine triphosphatase Rab5 to promote growth cone collapse and organize callosal axon projections. 2516 16