Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Carcinoembryonic antigen (CEA) was highly effectively extracted with phosphatidylinositol-specific phospholipase C (PI-PLC) from various source materials. The yield of CEA was, in some cases, 20-30 times more than that obtained by the usual method with perchloric acid. Addition of 0.1-0.2 units of PI-PLC to 1 g tumor tissue and incubation at 37 degrees C for 1 h with continuous shaking seem to be practically sufficient for CEA extraction. A simple purification procedure for CEA after extraction with PI-PLC is proposed. The immunochemical properties of CEA thus obtained were found to be identical to those of CEA obtained by the usual method.
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PMID:Highly effective extraction of carcinoembryonic antigen with phosphatidylinositol-specific phospholipase C. 185 20

Two molecular species of nonspecific cross-reacting antigens, NCA-90 and NCA-50 with mol. wts. of 90,000 and 50,000, respectively, were effectively extracted with phosphatidylinositol-specific phospholipase C (PI-PLC) from human lung tissues, followed by extraction with perchloric acid, immunoaffinity chromatography with anti-NCA adsorbent, and gel filtration on a TSK G3000SW column. The yields of NCA were about 2 times more than those obtained by the usual method without PI-PLC. Addition of 0.05 unit of PI-PLC to 1 g of lung tissue and incubation at 37 degrees C for 1 h with continuous shaking seem to be practically sufficient for NCA extraction. The immunochemical properties of the NCAs thus obtained were found to be identical to those of NCAs obtained by the ordinary method.
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PMID:Effective purification of nonspecific cross-reacting antigens with phosphatidylinositol-specific phospholipase C. 839 90

In physiology research, animal neurotoxins historically have served as valuable tools for identification, purification, and functional characterization of voltage-dependent ion channels. In particular, toxins from scorpions, sea anemones and cone snails were at the forefront of work aimed at illuminating the three-dimensional architecture of sodium channels. To date, at least six different receptor binding sites have been identified and--most of them--structurally assigned in terms of protein sequence and spatial disposition. Recent work on Australian funnel-web spiders identified certain peptidic ingredients as being responsible for the neurotoxicity of the crude venom. These peptides, termed delta-atracotoxins (delta-ACTX), consist of 42 amino acids and bind to voltage-gated sodium channels in the same way as classical scorpion alpha-toxins. According to the 'voltage-sensor trapping model' proposed in the literature, delta-ACTX isoforms interact with the voltage sensor S4 transmembrane segment of alpha-subunit domain IV, thereby preventing its normal outward movement and concurrent conformational changes required for inactivation of the channel. As consequence prolonged action potentials at autonomic or somatic synapses induce massive transmitter release, resulting in clinical correlates of neuroexcitation (e.g., muscle fasciculation, spasms, paresthesia, tachycardia, diaphoresis, etc.). On the other hand, the major neurotoxin isolated from black widow spiders, alpha-latrotoxin (alpha-LTX), represents a 132 kDa protein consisting of a unique N-terminal sequence and a C-terminal part harboring multiple ankyrin-like repeats. Upon binding to one of its specific presynaptic receptors, alpha-LTX has been shown to tetramerize under physiological conditions to form Ca2+-permeable pores in presynaptic membranes. The molecular model worked out during recent years separates two distinguishable receptor-mediated effects. According to current knowledge, binding of the N terminus of alpha-LTX at one of its specific receptors either triggers intracellular signaling cascades, resulting in phospholipase C-mediated mobilization of presynaptic Ca2+ stores, or leads to the formation of tetrameric pore complexes, allowing extracellular Ca2+ to enter the presynaptic terminal. Alpha-LTX-triggered exocytosis and fulminant transmitter release at autonomic synapses may then provoke a clinical syndrome referred to as 'latrodectism', characterized by local and incapacitating pain, diaphoresis, muscle fasciculation, tremor, anxiety, and so forth. The present review aims at providing a short introduction into some of the exciting molecular effects induced by neurotoxins isolated from black widow and funnel-web spiders.
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PMID:Mechanistic insights on spider neurotoxins. 2035 87