Sodium Channels: Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.Voltage-Gated Sodium Channel beta-1 Subunit: A voltage-gated sodium channel beta subunit abundantly expressed in SKELETAL MUSCLE; HEART; and BRAIN. It non-covalently associates with voltage-gated alpha subunits. Defects in the SCN1B gene, which codes for this beta subunit, are associated with generalized epilepsy with febrile seizures plus, type 1, and Brugada syndrome 5.Voltage-Gated Sodium Channel beta-2 Subunit: A voltage-gated sodium channel beta subunit that binds covalently to voltage-gated alpha subunits.Voltage-Gated Sodium Channel beta-4 Subunit: A voltage-gated sodium channel beta subunit subtype that covalently associates with voltage-gated alpha subunits. Defects in the SCN4B gene, which codes for this beta subunit, are associated with long QT syndrome-10.NAV1.2 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype that mediates the sodium ion permeability of excitable membranes. Defects in the SCN2A gene which codes for the alpha subunit of this sodium channel are associated with benign familial infantile seizures type 3, and early infantile epileptic encephalopathy type 11.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Voltage-Gated Sodium Channel beta-3 Subunit: A voltage-gated sodium channel beta subunit subtype that non-covalently associates with voltage-gated alpha subunits. Defects in the SCN3B gene which codes for this beta subunit are associated with Brugada syndrome 7.Ion Channel Gating: The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.Sodium Channel Blockers: A class of drugs that act by inhibition of sodium influx through cell membranes. Blockade of sodium channels slows the rate and amplitude of initial rapid depolarization, reduces cell excitability, and reduces conduction velocity.Ion Channels: Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.Sodium: A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.Voltage-Gated Sodium Channel beta Subunits: Voltage-gated sodium channel subunits that play a role in the assembly, expression, and functional modulation of the sodium channel. They form a heterotrimeric complex with the pore-forming sodium channel alpha subunits.Membrane Potentials: The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).Calcium Channels: Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.Contactins: A family of immunoglobulin-related cell adhesion molecules that are involved in NERVOUS SYSTEM patterning.NAV1.6 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype found widely expressed in neurons of the central and peripheral nervous systems. Defects in the SCN8A gene which codes for the alpha subunit of this sodium channel are associated with ATAXIA and cognitive deficits.Epithelial Sodium Channels: Sodium channels found on salt-reabsorbing EPITHELIAL CELLS that line the distal NEPHRON; the distal COLON; SALIVARY DUCTS; SWEAT GLANDS; and the LUNG. They are AMILORIDE-sensitive and play a critical role in the control of sodium balance, BLOOD VOLUME, and BLOOD PRESSURE.Shaker Superfamily of Potassium Channels: Voltage-gated potassium channels whose primary subunits contain six transmembrane segments and form tetramers to create a pore with a voltage sensor. They are related to their founding member, shaker protein, Drosophila.NAV1.8 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype that is expressed in nociceptors, including spinal and trigeminal sensory neurons. It plays a role in the transmission of pain signals induced by cold, heat, and mechanical stimuli.Saxitoxin: A compound that contains a reduced purine ring system but is not biosynthetically related to the purine alkaloids. It is a poison found in certain edible mollusks at certain times; elaborated by GONYAULAX and consumed by mollusks, fishes, etc. without ill effects. It is neurotoxic and causes RESPIRATORY PARALYSIS and other effects in MAMMALS, known as paralytic SHELLFISH poisoning.Protein Subunits: Single chains of amino acids that are the units of multimeric PROTEINS. Multimeric proteins can be composed of identical or non-identical subunits. One or more monomeric subunits may compose a protomer which itself is a subunit structure of a larger assembly.Patch-Clamp Techniques: An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.Tetrodotoxin: An aminoperhydroquinazoline poison found mainly in the liver and ovaries of fishes in the order TETRAODONTIFORMES, which are eaten. The toxin causes paresthesia and paralysis through interference with neuromuscular conduction.Cations: Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.NAV1.5 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype that mediates the sodium ion PERMEABILITY of CARDIOMYOCYTES. Defects in the SCN5A gene, which codes for the alpha subunit of this sodium channel, are associated with a variety of CARDIAC DISEASES that result from loss of sodium channel function.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Large-Conductance Calcium-Activated Potassium Channels: A major class of calcium activated potassium channels whose members are voltage-dependent. MaxiK channels are activated by either membrane depolarization or an increase in intracellular Ca(2+). They are key regulators of calcium and electrical signaling in a variety of tissues.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Potassium Channels, Inwardly Rectifying: Potassium channels where the flow of K+ ions into the cell is greater than the outward flow.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Electrophysiology: The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.Scorpion Venoms: Venoms from animals of the order Scorpionida of the class Arachnida. They contain neuro- and hemotoxins, enzymes, and various other factors that may release acetylcholine and catecholamines from nerve endings. Of the several protein toxins that have been characterized, most are immunogenic.Xenopus laevis: The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.Voltage-Gated Sodium Channels: A family of membrane proteins that selectively conduct SODIUM ions due to changes in the TRANSMEMBRANE POTENTIAL DIFFERENCE. They typically have a multimeric structure with a core alpha subunit that defines the sodium channel subtype and several beta subunits that modulate sodium channel activity.Calcium Channel Blockers: A class of drugs that act by selective inhibition of calcium influx through cellular membranes.TRPM Cation Channels: A subgroup of TRP cation channels named after melastatin protein. They have the TRP domain but lack ANKYRIN repeats. Enzyme domains in the C-terminus leads to them being called chanzymes.Potassium Channel Blockers: A class of drugs that act by inhibition of potassium efflux through cell membranes. Blockade of potassium channels prolongs the duration of ACTION POTENTIALS. They are used as ANTI-ARRHYTHMIA AGENTS and VASODILATOR AGENTS.Electric Conductivity: The ability of a substrate to allow the passage of ELECTRONS.TRPC Cation Channels: A subgroup of TRP cation channels that contain 3-4 ANKYRIN REPEAT DOMAINS and a conserved C-terminal domain. Members are highly expressed in the CENTRAL NERVOUS SYSTEM. Selectivity for calcium over sodium ranges from 0.5 to 10.Chloride Channels: Cell membrane glycoproteins that form channels to selectively pass chloride ions. Nonselective blockers include FENAMATES; ETHACRYNIC ACID; and TAMOXIFEN.Kinetics: The rate dynamics in chemical or physical systems.Calcium Channels, L-Type: Long-lasting voltage-gated CALCIUM CHANNELS found in both excitable and nonexcitable tissue. They are responsible for normal myocardial and vascular smooth muscle contractility. Five subunits (alpha-1, alpha-2, beta, gamma, and delta) make up the L-type channel. The alpha-1 subunit is the binding site for calcium-based antagonists. Dihydropyridine-based calcium antagonists are used as markers for these binding sites.Oocytes: Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).Pyrethrins: The active insecticidal constituent of CHRYSANTHEMUM CINERARIIFOLIUM flowers. Pyrethrin I is the pyretholone ester of chrysanthemummonocarboxylic acid and pyrethrin II is the pyretholone ester of chrysanthemumdicarboxylic acid monomethyl ester.Potassium Channels, Voltage-Gated: Potassium channel whose permeability to ions is extremely sensitive to the transmembrane potential difference. The opening of these channels is induced by the membrane depolarization of the ACTION POTENTIAL.Sodium Channel Agonists: A class of drugs that stimulate sodium influx through cell membrane channels.Large-Conductance Calcium-Activated Potassium Channel beta Subunits: The regulatory subunits of large-conductance calcium-activated potassium channels.NAV1.4 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype that mediates the sodium ion PERMEABILITY of SKELETAL MYOCYTES. Defects in the SCN4A gene, which codes for the alpha subunit of this sodium channel, are associated with several MYOTONIC DISORDERS.NAV1.1 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype that is predominantly expressed in the CENTRAL NERVOUS SYSTEM. Defects in the SCN1A gene which codes for the alpha subunit of this sodium channel are associated with DRAVET SYNDROME, generalized epilepsy with febrile seizures plus, type 2 (GEFS+2), and familial hemiplegic migraine type 3.Potassium Channels, Calcium-Activated: Potassium channels whose activation is dependent on intracellular calcium concentrations.Calcium: A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Cell Line: Established cell cultures that have the potential to propagate indefinitely.NAV1.7 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype found widely expressed in nociceptive primary sensory neurons. Defects in the SCN9A gene, which codes for the alpha subunit of this sodium channel, are associated with several pain sensation-related disorders.Xenopus: An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.TRPV Cation Channels: A subgroup of TRP cation channels named after vanilloid receptor. They are very sensitive to TEMPERATURE and hot spicy food and CAPSAICIN. They have the TRP domain and ANKYRIN repeats. Selectivity for CALCIUM over SODIUM ranges from 3 to 100 fold.Potassium: An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Cyclic Nucleotide-Gated Cation Channels: A subgroup of cyclic nucleotide-regulated ION CHANNELS within the superfamily of pore-loop cation channels. They are expressed in OLFACTORY NERVE cilia and in PHOTORECEPTOR CELLS and some PLANTS.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Batrachotoxins: Batrachotoxin is the 20-alpha-bromobenzoate of batrachotoxin A; they are toxins from the venom of a small Colombian frog, Phyllobates aurotaenia, cause release of acetylcholine, destruction of synaptic vesicles and depolarization of nerve and muscle fibers.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Calcium Channels, N-Type: CALCIUM CHANNELS that are concentrated in neural tissue. Omega toxins inhibit the actions of these channels by altering their voltage dependence.KATP Channels: Heteromultimers of Kir6 channels (the pore portion) and sulfonylurea receptor (the regulatory portion) which affect function of the HEART; PANCREATIC BETA CELLS; and KIDNEY COLLECTING DUCTS. KATP channel blockers include GLIBENCLAMIDE and mitiglinide whereas openers include CROMAKALIM and minoxidil sulfate.NAV1.3 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype found in neuronal tissue that mediates the sodium ion PERMEABILITY of excitable membranes.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Action Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Acid Sensing Ion Channels: A family of proton-gated sodium channels that are primarily expressed in neuronal tissue. They are AMILORIDE-sensitive and are implicated in the signaling of a variety of neurological stimuli, most notably that of pain in response to acidic conditions.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Voltage-Gated Sodium Channel Blockers: A class of drugs that inhibit the activation of VOLTAGE-GATED SODIUM CHANNELS.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Amiloride: A pyrazine compound inhibiting SODIUM reabsorption through SODIUM CHANNELS in renal EPITHELIAL CELLS. This inhibition creates a negative potential in the luminal membranes of principal cells, located in the distal convoluted tubule and collecting duct. Negative potential reduces secretion of potassium and hydrogen ions. Amiloride is used in conjunction with DIURETICS to spare POTASSIUM loss. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p705)Protein Structure, Secondary: The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.Calcium Channels, T-Type: A heterogenous group of transient or low voltage activated type CALCIUM CHANNELS. They are found in cardiac myocyte membranes, the sinoatrial node, Purkinje cells of the heart and the central nervous system.Veratridine: A benzoate-cevane found in VERATRUM and Schoenocaulon. It activates SODIUM CHANNELS to stay open longer than normal.Intracellular Membranes: Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.Cell Membrane Permeability: A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Transient Receptor Potential Channels: A broad group of eukaryotic six-transmembrane cation channels that are classified by sequence homology because their functional involvement with SENSATION is varied. They have only weak voltage sensitivity and ion selectivity. They are named after a DROSOPHILA mutant that displayed transient receptor potentials in response to light. A 25-amino-acid motif containing a TRP box (EWKFAR) just C-terminal to S6 is found in TRPC, TRPV and TRPM subgroups. ANKYRIN repeats are found in TRPC, TRPV & TRPN subgroups. Some are functionally associated with TYROSINE KINASE or TYPE C PHOSPHOLIPASES.Cations, Divalent: Positively charged atoms, radicals or groups of atoms with a valence of plus 2, which travel to the cathode or negative pole during electrolysis.Potassium Channels: Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.Protein Transport: The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.NAV1.9 Voltage-Gated Sodium Channel: A voltage-gated sodium channel subtype found in the neurons of the NERVOUS SYSTEM and DORSAL ROOT GANGLIA. It may play a role in the generation of heat and mechanical pain hypersensitivity.Ion Transport: The movement of ions across energy-transducing cell membranes. Transport can be active, passive or facilitated. Ions may travel by themselves (uniport), or as a group of two or more ions in the same (symport) or opposite (antiport) directions.Kv1.2 Potassium Channel: A delayed rectifier subtype of shaker potassium channels that is selectively inhibited by a variety of SCORPION VENOMS.Lipid Bilayers: Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.Membranes: Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Protein Structure, Quaternary: The characteristic 3-dimensional shape and arrangement of multimeric proteins (aggregates of more than one polypeptide chain).Ether-A-Go-Go Potassium Channels: A family of voltage-gated potassium channels that are characterized by long N-terminal and C-terminal intracellular tails. They are named from the Drosophila protein whose mutation causes abnormal leg shaking under ether anesthesia. Their activation kinetics are dependent on extracellular MAGNESIUM and PROTON concentration.Bacterial Outer Membrane Proteins: Proteins isolated from the outer membrane of Gram-negative bacteria.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Epithelial Sodium Channel Blockers: A subclass of sodium channel blockers that are specific for EPITHELIAL SODIUM CHANNELS.Cations, Monovalent: Positively charged atoms, radicals or group of atoms with a valence of plus 1, which travel to the cathode or negative pole during electrolysis.Lidocaine: A local anesthetic and cardiac depressant used as an antiarrhythmia agent. Its actions are more intense and its effects more prolonged than those of PROCAINE but its duration of action is shorter than that of BUPIVACAINE or PRILOCAINE.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Barium: An element of the alkaline earth group of metals. It has an atomic symbol Ba, atomic number 56, and atomic weight 138. All of its acid-soluble salts are poisonous.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Adenosine Triphosphate: An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.Degenerin Sodium Channels: A family of mechanosensitive sodium channels found primarily in NEMATODES where they play a role in CELLULAR MECHANOTRANSDUCTION. Degenerin sodium channels are structurally-related to EPITHELIAL SODIUM CHANNELS and are named after the fact that loss of their activity results in cellular degeneration.Nerve Tissue ProteinsHydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Time Factors: Elements of limited time intervals, contributing to particular results or situations.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Kv1.1 Potassium Channel: A delayed rectifier subtype of shaker potassium channels that is commonly mutated in human episodic ATAXIA and MYOKYMIA.Membrane Lipids: Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.Calcium Channel Agonists: Agents that increase calcium influx into calcium channels of excitable tissues. This causes vasoconstriction in VASCULAR SMOOTH MUSCLE and/or CARDIAC MUSCLE cells as well as stimulation of insulin release from pancreatic islets. Therefore, tissue-selective calcium agonists have the potential to combat cardiac failure and endocrinological disorders. They have been used primarily in experimental studies in cell and tissue culture.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Kv1.3 Potassium Channel: A delayed rectifier subtype of shaker potassium channels that is the predominant VOLTAGE-GATED POTASSIUM CHANNEL of T-LYMPHOCYTES.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: A subgroup of cyclic nucleotide-regulated ION CHANNELS of the superfamily of pore-loop cation channels that are opened by hyperpolarization rather than depolarization. The ion conducting pore passes SODIUM, CALCIUM, and POTASSIUM cations with a preference for potassium.Myocardium: The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Large-Conductance Calcium-Activated Potassium Channel alpha Subunits: The pore-forming subunits of large-conductance calcium-activated potassium channels. They form tetramers in CELL MEMBRANES.Ranvier's Nodes: Regularly spaced gaps in the myelin sheaths of peripheral axons. Ranvier's nodes allow saltatory conduction, that is, jumping of impulses from node to node, which is faster and more energetically favorable than continuous conduction.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Tetraethylammonium: A potassium-selective ion channel blocker. (From J Gen Phys 1994;104(1):173-90)Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Chlorides: Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.Membrane Microdomains: Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.KCNQ1 Potassium Channel: A voltage-gated potassium channel that is expressed primarily in the HEART.KCNQ Potassium Channels: A family of delayed rectifier voltage-gated potassium channels that share homology with their founding member, KCNQ1 PROTEIN. KCNQ potassium channels have been implicated in a variety of diseases including LONG QT SYNDROME; DEAFNESS; and EPILEPSY.Kv1.5 Potassium Channel: A delayed rectifier subtype of shaker potassium channels that conducts a delayed rectifier current. It contributes to ACTION POTENTIAL repolarization of MYOCYTES in HEART ATRIA.Escherichia coli Proteins: Proteins obtained from ESCHERICHIA COLI.Membranes, Artificial: Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Decapodiformes: A superorder of CEPHALOPODS comprised of squid, cuttlefish, and their relatives. Their distinguishing feature is the modification of their fourth pair of arms into tentacles, resulting in 10 limbs.Protein Isoforms: Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.Small-Conductance Calcium-Activated Potassium Channels: A major class of calcium-activated potassium channels that are found primarily in excitable CELLS. They play important roles in the transmission of ACTION POTENTIALS and generate a long-lasting hyperpolarization known as the slow afterhyperpolarization.HEK293 Cells: A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.Biophysics: The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Shab Potassium Channels: A subfamily of shaker potassium channels that shares homology with its founding member, Shab protein, Drosophila. They regulate delayed rectifier currents in the NERVOUS SYSTEM of DROSOPHILA and in the SKELETAL MUSCLE and HEART of VERTEBRATES.Ganglia, Spinal: Sensory ganglia located on the dorsal spinal roots within the vertebral column. The spinal ganglion cells are pseudounipolar. The single primary branch bifurcates sending a peripheral process to carry sensory information from the periphery and a central branch which relays that information to the spinal cord or brain.Macromolecular Substances: Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.Caveolin 1: A tyrosine phosphoprotein that plays an essential role in CAVEOLAE formation. It binds CHOLESTEROL and is involved in LIPIDS transport, membrane traffic, and SIGNAL TRANSDUCTION.Shaw Potassium Channels: A shaker subfamily that is prominently expressed in NEURONS and are necessary for high-frequency, repetitive firing of ACTION POTENTIALS.Kv1.4 Potassium Channel: A fast inactivating subtype of shaker potassium channels that contains two inactivation domains at its N terminus.Axons: Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.Endopeptidase Clp: An ATP-dependent protease found in prokaryotes, CHLOROPLASTS, and MITOCHONDRIA. It is a soluble multisubunit complex that plays a role in the degradation of many abnormal proteins.Conotoxins: Peptide neurotoxins from the marine fish-hunting snails of the genus CONUS. They contain 13 to 29 amino acids which are strongly basic and are highly cross-linked by disulfide bonds. There are three types of conotoxins, omega-, alpha-, and mu-. OMEGA-CONOTOXINS inhibit voltage-activated entry of calcium into the presynaptic membrane and therefore the release of ACETYLCHOLINE. Alpha-conotoxins inhibit the postsynaptic acetylcholine receptor. Mu-conotoxins prevent the generation of muscle action potentials. (From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed)Oxocins: Compounds based on an 8-membered heterocyclic ring including an oxygen. They can be considered medium ring ethers.Cesium: A member of the alkali metals. It has an atomic symbol Cs, atomic number 50, and atomic weight 132.91. Cesium has many industrial applications, including the construction of atomic clocks based on its atomic vibrational frequency.Mexiletine: Antiarrhythmic agent pharmacologically similar to LIDOCAINE. It may have some anticonvulsant properties.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Guinea Pigs: A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.Ankyrins: A family of membrane-associated proteins responsible for the attachment of the cytoskeleton. Erythrocyte-related isoforms of ankyrin attach the SPECTRIN cytoskeleton to a transmembrane protein (ANION EXCHANGE PROTEIN 1, ERYTHROCYTE) in the erythrocyte plasma membrane. Brain-related isoforms of ankyrin also exist.Sodium Chloride: A ubiquitous sodium salt that is commonly used to season food.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Magnesium: A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Neurotoxins: Toxic substances from microorganisms, plants or animals that interfere with the functions of the nervous system. Most venoms contain neurotoxic substances. Myotoxins are included in this concept.DNA, Complementary: Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.Biophysical Phenomena: The physical characteristics and processes of biological systems.Permeability: Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.Amino Acid Substitution: The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.Shal Potassium Channels: A shaker subfamily of potassium channels that participate in transient outward potassium currents by activating at subthreshold MEMBRANE POTENTIALS, inactivating rapidly, and recovering from inactivation quickly.CHO Cells: CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.Flufenamic Acid: An anthranilic acid derivative with analgesic, anti-inflammatory, and antipyretic properties. It is used in musculoskeletal and joint disorders and administered by mouth and topically. (From Martindale, The Extra Pharmacopoeia, 30th ed, p16)Scorpions: Arthropods of the order Scorpiones, of which 1500 to 2000 species have been described. The most common live in tropical or subtropical areas. They are nocturnal and feed principally on insects and other arthropods. They are large arachnids but do not attack man spontaneously. They have a venomous sting. Their medical significance varies considerably and is dependent on their habits and venom potency rather than on their size. At most, the sting is equivalent to that of a hornet but certain species possess a highly toxic venom potentially fatal to humans. (From Dorland, 27th ed; Smith, Insects and Other Arthropods of Medical Importance, 1973, p417; Barnes, Invertebrate Zoology, 5th ed, p503)Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Ions: An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.Marine Toxins: Toxic or poisonous substances elaborated by marine flora or fauna. They include also specific, characterized poisons or toxins for which there is no more specific heading, like those from poisonous FISHES.Spider Venoms: Venoms of arthropods of the order Araneida of the ARACHNIDA. The venoms usually contain several protein fractions, including ENZYMES, hemolytic, neurolytic, and other TOXINS, BIOLOGICAL.Cockroaches: Insects of the order Dictyoptera comprising several families including Blaberidae, BLATTELLIDAE, Blattidae (containing the American cockroach PERIPLANETA americana), Cryptocercidae, and Polyphagidae.G Protein-Coupled Inwardly-Rectifying Potassium Channels: A family of inwardly-rectifying potassium channels that are activated by PERTUSSIS TOXIN sensitive G-PROTEIN-COUPLED RECEPTORS. GIRK potassium channels are primarily activated by the complex of GTP-BINDING PROTEIN BETA SUBUNITS and GTP-BINDING PROTEIN GAMMA SUBUNITS.Nuclear Pore: An opening through the NUCLEAR ENVELOPE formed by the nuclear pore complex which transports nuclear proteins or RNA into or out of the CELL NUCLEUS and which, under some conditions, acts as an ion channel.KCNQ2 Potassium Channel: A very slow opening and closing voltage-gated potassium channel that is expressed in NEURONS and is commonly mutated in BENIGN FAMILIAL NEONATAL CONVULSIONS.Peptides: Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Blotting, Western: Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.Molecular Weight: The sum of the weight of all the atoms in a molecule.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Adenosine Triphosphatases: A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.Ryanodine Receptor Calcium Release Channel: A tetrameric calcium release channel in the SARCOPLASMIC RETICULUM membrane of SMOOTH MUSCLE CELLS, acting oppositely to SARCOPLASMIC RETICULUM CALCIUM-TRANSPORTING ATPASES. It is important in skeletal and cardiac excitation-contraction coupling and studied by using RYANODINE. Abnormalities are implicated in CARDIAC ARRHYTHMIAS and MUSCULAR DISEASES.RNA, Complementary: Synthetic transcripts of a specific DNA molecule or fragment, made by an in vitro transcription system. This cRNA can be labeled with radioactive uracil and then used as a probe. (King & Stansfield, A Dictionary of Genetics, 4th ed)Erythrocyte Membrane: The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Receptors, Drug: Proteins that bind specific drugs with high affinity and trigger intracellular changes influencing the behavior of cells. Drug receptors are generally thought to be receptors for some endogenous substance not otherwise specified.Bacterial Proteins: Proteins found in any species of bacterium.Epithelial Sodium Channel Agonists: Compounds that either stimulate the opening or prevent closure of EPITHELIAL SODIUM ION CHANNELS.Muscle Proteins: The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.Tetraethylammonium CompoundsHeart: The hollow, muscular organ that maintains the circulation of the blood.Muscles: Contractile tissue that produces movement in animals.Calcium Channels, P-Type: CALCIUM CHANNELS located within the PURKINJE CELLS of the cerebellum. They are involved in stimulation-secretion coupling of neurons.Glyburide: An antidiabetic sulfonylurea derivative with actions similar to those of chlorpropamide.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Cnidarian Venoms: Venoms from jellyfish; CORALS; SEA ANEMONES; etc. They contain hemo-, cardio-, dermo- , and neuro-toxic substances and probably ENZYMES. They include palytoxin, sarcophine, and anthopleurine.Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.Sodium, Dietary: Sodium or sodium compounds used in foods or as a food. The most frequently used compounds are sodium chloride or sodium glutamate.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Porins: Porins are protein molecules that were originally found in the outer membrane of GRAM-NEGATIVE BACTERIA and that form multi-meric channels for the passive DIFFUSION of WATER; IONS; or other small molecules. Porins are present in bacterial CELL WALLS, as well as in plant, fungal, mammalian and other vertebrate CELL MEMBRANES and MITOCHONDRIAL MEMBRANES.TRPP Cation Channels: A subgroup of TRP cation channels that are widely expressed in various cell types. Defects are associated with POLYCYSTIC KIDNEY DISEASES.KCNQ3 Potassium Channel: A very slow opening and closing voltage-gated potassium channel that is expressed in NEURONS and is closely related to KCNQ2 POTASSIUM CHANNEL. It is commonly mutated in BENIGN FAMILIAL NEONATAL CONVULSIONS.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
Voltage-gated sodium channels normally consist of an alpha subunit that forms the ion conduction pore and one to two beta ... Sodium channels are integral membrane proteins that form ion channels, conducting sodium ions (Na+) through a cell's plasma ... This suggests that an ancestral form of the animal channel was among the many proteins that play central roles in animal life, ... The cations flow into a more constricted part of the pore that is 0.3 by 0.5 nm wide, which is just large enough to allow a ...
... "leak channels" that set the negative membrane potential of neurons. Voltage-gated potassium channel - are voltage-gated ion ... All potassium channel subunits have a distinctive pore-loop structure that lines the top of the pore and is responsible for ... Sauer, DB; Zeng, W; Raghunathan, S; Jiang, Y (4 October 2011). "Protein interactions central to stabilizing the K+ channel ... family Potassium uptake permease Sodium ion channel Calcium channel Littleton JT, Ganetzky B (Apr 2000). "Ion channels and ...
"ATP-gated P2X Receptor Cation Channel (P2X Receptor) Family". Functional and Phylogenetic Classification of Membrane Transport ... All three subunits are essential for transport to the membrane assembly of functional channels on the membrane. The C-terminus ... postulated to contribute to the formation of the hydrophilic pores of the oligomeric channel protein complexes. It is thought ... "Gene structure of the human amiloride-sensitive epithelial sodium channel beta subunit". Biochemical and Biophysical Research ...
Na+, K+, and Ca2+ channels are composed of four transmembrane α-subunits arranged around a central pore. The membrane-spanning ... Phylogenetic studies of proteins expressed in bacteria revealed the existence of a superfamily of voltage-gated sodium channels ... polycystin cation channels, glutamate-gated ion channels, calcium-dependent chloride channels, monovalent cation:proton ... ISBN 978-0-7167-3136-8. Gulbis JM, Mann S, MacKinnon R (June 1999). "Structure of a voltage-dependent K+ channel beta subunit ...
A CNG channel consists of four subunits around a central pore. Each protein subunit consists 6 transmembrane segments (S1-S6), ... CNG channels are nonselective cation channels that are found in the membranes of various tissue and cell types, and are ... Cyclic nucleotide-gated channel beta 1 Cyclic nucleotide-gated channel beta 3 The structure of the pore is similar to other ion ... Ion channel HCN channel Voltage-dependent calcium channel Fesenko EE, Kolesnikov SS, Lyubarsky AL; Kolesnikov; Lyubarsky (1985 ...
The voltage-dependence of current through the channel is mainly due to binding of Mg2+ or Zn2+ ions to the protein as described ... The membrane domain contributes residues to the channel pore and is responsible for the receptor's high-unitary conductance, ... proteins and the polyamines spermidine and spermine are also modulators for the NMDA receptor channels. The NR2B subunit has ... While it is primarily a ligand-gated channel, it does display weaker voltage-dependence modulation of the ligand-dependent ...
The cell membrane of the axon and soma contain voltage-gated ion channels that allow the neuron to generate and propagate an ... Nicotinic receptors are pentameric ligand-gated ion channels composed of alpha and beta subunits that bind nicotine. Ligand ... permeable to Na+ cation channels mediating fast excitatory synaptic transmission NMDA receptors are another cation channel that ... Glutamate receptors are one of four categories, three of which are ligand-gated ion channels and one of which is a G-protein ...
... parts of the protein that pass through the plasma membrane), proteins interacting with the subunit indicated that the N- ... The AMPAR's permeability to calcium and other cations, such as sodium and potassium, is governed by the GluA2 subunit. If an ... polyamines will block the AMPAR channel more strongly, preventing the flux of potassium ions through the channel pore. GluA2- ... However, AMPAR endocytosis has also been activated by voltage-dependent calcium channels, agonism of AMPA receptors, and ...
Membrane transport protein: ion channels (TC 1A). Ca2+: Calcium channel. Ligand-gated. *Inositol trisphosphate receptor *1 ... Gap junction beta-1 protein (GJB1), also known as connexin 32 (Cx32) is a transmembrane protein that in humans is encoded by ... affect the peripheral nervous system some cases have been reported in which there is evidence of demyelination of the central ... γ-subunits *γ1. *γ2. *γ3. *γ4. *Cation channels of sperm *1. *2 ...
β Subunit[edit]. The intracellular β subunit (55 kDa) is an intracellular MAGUK-like protein (Membrane-Associated Guanylate ... "Adaptive evolution of voltage-gated sodium channels: the first 800 million years" (PDF). Proceedings of the National Academy of ... α1 Subunit[edit]. The α1 subunit pore (~190 kDa in molecular mass) is the primary subunit necessary for channel functioning in ... Some of these effects are observed in the absence of the beta subunit, whereas, in other cases, the co-expression of beta is ...
As with all ligand-gated ion channels, opening of the nAChR channel pore requires the binding of a chemical messenger. Several ... arranged symmetrically around a central pore. Each subunit comprises four transmembrane domains with both the N- and C-terminus ... On one hand, the movement of cations causes a depolarization of the plasma membrane (which results in an excitatory ... The amount of sodium and potassium the channels allow through their pores (their conductance) varies from 50-110 pS, with the ...
... parts of the protein that pass through the plasma membrane), proteins interacting with the subunit indicated that the N- ... Ion channel, cell surface receptor: ligand-gated ion channels. Cys-loop receptors. ... The AMPAR's permeability to calcium and other cations, such as sodium and potassium, is governed by the GluA2 subunit. If an ... polyamines will block the AMPAR channel more strongly, preventing the flux of potassium ions through the channel pore. GluA2- ...
... channel), voltage gated potassium channel HBK1, voltage gated potassium channel subunit Kv1.1, voltage-gated K+ channel HuKI ... 1exb: STRUCTURE OF THE CYTOPLASMIC BETA SUBUNIT-T1 ASSEMBLY OF VOLTAGE-DEPENDENT K CHANNELS ... The protein is believed to have six domains (S1-S6) with the loop between S5 and S6 forming the channel pore. This region also ... voltage-gated ion channel activity involved in regulation of presynaptic membrane potential. • voltage-gated ion channel ...
Membrane transport protein: ion channels (TC 1A). Ca2+: Calcium channel. Ligand-gated. *Inositol trisphosphate receptor *1 ... although different connexin subunits may impart different pore sizes and different charge selectivity. Large biomolecules, for ... Electrical synapses are present throughout the central nervous system and have been studied specifically in the neocortex, ... "Reduced expression of Cx43 attenuates ventricular remodeling after myocardial infarction via impaired TGF-beta signaling". Am ...
Pore-forming subunit of a voltage-gated sodium channel complex through which Na(+) ions pass in accordance with their ... Pore-forming subunit of a voltage-gated sodium channel complex through which Na+ ions pass in accordance with their ... Plasma Membrane. *integral component of plasma membrane Source: UniProtKB. *plasma membrane Source: GO_CentralInferred from ... voltage-sensitive sodium channel complex that consists of a pore-forming alpha subunit and one or more regulatory beta subunits ...
... the existence of a voltage-activated non-selective cation channel was functionally demonstrated utilizing the patch-clamp ... that the low ionic strength-induced cation permeability in RBCs is not due to electrodiffusion but due to a transport protein- ... the existence of ion transport dependent on the membrane potential was reported for the first time approximately 50 years ago ( ... and it has alternatively been proposed to reflect a conductance state of the voltage-dependent anion channel (VDAC) (Bouyer et ...
PPore-forming subunit of a voltage-gated sodium channel complex through which Na(+) ions pass in accordance with their ... voltage-sensitive sodium channel complex that consists of a pore-forming alpha subunit and one or more regulatory beta subunits ... plasma membrane Source: GO_CentralInferred from biological aspect of ancestori*. "Phylogenetic-based propagation of functional ... PPore-forming subunit of a voltage-gated sodium channel complex through which Na+ ions pass in accordance with their ...
... conducting sodium ions (Na+) through a cells plasma membrane. They may ... Sodium channel Sodium channels are integral membrane proteins that form ion channels, ... Voltage-gated sodium channels normally consist of an alpha subunit which forms the ion conduction pore and one to two beta ... Protein name Gene Auxiliary subunits Expression profile Associated human channelopathies Navα1.1 SCN1A β1,β2,β3,β4 Central ...
Voltage-gated sodium channels normally consist of an alpha subunit that forms the ion conduction pore and one to two beta ... Sodium channels are integral membrane proteins that form ion channels, conducting sodium ions (Na+) through a cells plasma ... This suggests that an ancestral form of the animal channel was among the many proteins that play central roles in animal life, ... The cations flow into a more constricted part of the pore that is 0.3 by 0.5 nm wide, which is just large enough to allow a ...
"ATP-gated P2X Receptor Cation Channel (P2X Receptor) Family". Functional and Phylogenetic Classification of Membrane Transport ... All three subunits are essential for transport to the membrane assembly of functional channels on the membrane. The C-terminus ... postulated to contribute to the formation of the hydrophilic pores of the oligomeric channel protein complexes. It is thought ... "Gene structure of the human amiloride-sensitive epithelial sodium channel beta subunit". Biochemical and Biophysical Research ...
... are a feature of voltage gated ion channel (VGICs) and voltage sensitive proteins. They are composed of four transmembrane (TM ... For example, gating pores in Nav1.5 and Kv7.2 channels may underlie mixed arrhythmias associated with dilated cardiomyopathy ( ... S4-GCTC interactions allows these crevices to communicate and create a fast activating and non-inactivating alternative cation- ... are a feature of voltage gated ion channel (VGICs) and voltage sensitive proteins. They are composed of four transmembrane (TM ...
Ion channels are membrane proteins that are used by the cell as signal transducers and as a pathway for the rapid entry of some ... A molecular blueprint for the pore-forming structure of voltage-gated calcium channels. Proc. Natl. Acad. Sci. USA, 88: 6418- ... Cation selectivity characteristics of the reconstituted voltage-dependent sodium channel purified from rat skeletal muscle ... Calcium channels reconstituted from the skeletal muscle dihydropyridine receptor protein complex and its a, peptide subunit in ...
View Proteins belonging to: The ATP-gated P2X Receptor Cation Channel (P2X Receptor) Family ... The three inter-subunit ATP binding sites are linked to the pore forming transmembrane (TM) domains by beta-strands. Structural ... P2X Receptor channels are probably hetero- or homomultimers of several subunits and transport small monovalent cations (Me+). ... P2X2 has a voltage-dependent gating property even though it lacks a canonical voltage sensor. It is a trimer in which each ...
Sodium channels (also known as "voltage-gated sodium channels") are integral membrane proteins that conduct sodium ions (Na+) ... Sodium channels normally consist of an alpha subunit which forms the ion conduction pore and one to two beta subunits which ... Auxiliary subunits. Expression profile. Associated human channelopathies Navα1.1 SCN1A. β1,β2,β3,β4. Central neurons and ... The cations flow into a more constricted part of the pore that is 0.3 by 0.5 nm wide, which is just large enough to allow a ...
... one G protein-coupled inwardly rectifying potassium channel activator (flupirtine), one sodium channel activator (BDF 9148/ ... Key roles of Phe1112 and Ser1115 in the pore-forming IIIS5-S6 linker of L-type Ca2+ channel α1C subunit (CaV 1.2) in binding of ... in the case of gating modifiers, as a result of faster activation, slower deactivation, altered voltage-dependence, or a ... Cation channels are membrane proteins that provide controlled pathways for ion passage through cellular membranes. They play ...
R. Ramracheya et al., Membrane potential-dependent inactivation of voltage-gated ion channels in alpha-cells inhibits glucagon ... T. Suzuki et al., Two different zinc transport complexes of cation diffusion facilitator proteins localized in the secretory ... a role for the L-type voltage-gated Ca2+ channel. J. Biol. Chem. 281(14), 9361-9372 (2006)PubMedGoogle Scholar ... X.P. Chu et al., Subunit-dependent high-affinity zinc inhibition of acid-sensing ion channels. J. Neurosci. 24(40), 8678-8689 ( ...
Some of these channels are opened when the voltage across the cell membrane changes. One subtype of these "voltage-gated" ... beta]/[gamma]-subunits), which dissociate from the receptor protein. The liberated [alpha]- and [beta]/[gamma]-subunits then ... cations) to flow across the membrane. Activation of such a receptor will mainly result in an influx of sodium into the cell, ... ligand-gated ion channel (LGIC) receptors and G-protein-coupled receptors (GPCRs). LGIC receptors are proteins specialized for ...
Locale about Experts and Doctors on sodium channels in United States ... beta subunit is likely to affect both protein-protein interactions and physiological function of multiple sodium channel alpha ... Payandeh J, Gamal El Din T, Scheuer T, Zheng N, Catterall W. Crystal structure of a voltage-gated sodium channel in two ... Multiple pore conformations driven by asynchronous movements of voltage sensors in a eukaryotic sodium channel. Nat Commun. ...
... γ subunits interact with other calcium channels and glutamate receptors and possibly with other membrane signaling proteins ( ... access of substituted amine blockers to the pore from the intracellular side of voltage-gated sodium and potassium channels ( ... Structure of the cytoplasmic beta subunit-T1 assembly of voltage-dependent potassium channels. Science (Wash DC) 289: 123-127. ... or nonselective cation channels) and primary gating mechanism (voltage, cyclic nucleotides, or both). An additional surprise is ...
... are ionotropic receptors that form ligand-gated ion ... Ion channel, receptor: ligand-gated ion channels. Cys-loop ... the α subunits become more similar to the other subunits, the channel becomes more symmetrical,[5] and a pore with a diameter ... On one hand, the movements of cations cause a depolarization of the plasma membrane, which results in an excitation, ... The amount of sodium and potassium the channels allow through their pores (their conductance) varies from 50-110 pS, with the ...
MPS-1 is a single-transmembrane domain protein that coassembles with voltage-gated K+ channel KVS-1 in the nervous system of ... Dec, 2003 , Pubmed ID: 14563681 Voltage-gated potassium channels formed with the cardiac subunit HERG and a polymorphic variant ... thereby providing maximum flexibility and scope for facilitating monovalent cation flux across the SR membrane. ... This channel is composed of a pore-forming subunit, dubbed KHT-1 (73% homology to human Kv3.1), and the accessory subunit MPS-1 ...
Voltage-gated sodium (Nav) channels are required for impulse conductance in excitable. 8 May 2017 ovarian ... Nav is usually a pore forming trans-membrane protein composed of a large α subunit (>200 kDa) and at least two associated β ... human prostate cancer cell lines and explored the clinical relevance of a particular voltage gated sodium channel Nav1.8 in ... Polyamines are crucial organic cations necessary for proteins and nucleic acidity synthesis and for that reason cell ...
β Subunit[edit]. The intracellular β subunit (55 kDa) is an intracellular MAGUK-like protein (Membrane-Associated Guanylate ... "Adaptive evolution of voltage-gated sodium channels: the first 800 million years" (PDF). Proceedings of the National Academy of ... α1 Subunit[edit]. The α1 subunit pore (~190 kDa in molecular mass) is the primary subunit necessary for channel functioning in ... Some of these effects are observed in the absence of the beta subunit, whereas, in other cases, the co-expression of beta is ...
2016). Coupling of a voltage-gated Ca2+ channel homologue with a plasma membrane H+ -ATPase in yeast. Genes Cells. [Epub: Ahead ... However, in mammals, these ATPases act in concert with members of the CDC50 protein family, putative beta-subunits for these ... binds to the ATPase with a Kd of 20 pM and creates a monovalent cation-selective channel with a single channel conductance of ... The γ-subunit of the Na+,K+-ATPase has been reported to influence kinetic parameters and is homologous to a family of pore- ...
... protein related to voltage-gated sodium and calcium channels. Biochem Biophys Res Commun 270:370-376PubMedCrossRefGoogle ... Given the principal topology of pore-loop cation channels, it is very likely that two TPCN channel subunits assemble to form a ... A new ER trafficking signal regulates the subunit stoichiometry of plasma membrane K(ATP) channels. Neuron 22:537-548PubMed ... a new second messenger for glucose-induced Ca2+ responses in clonal pancreatic beta cells. Curr Biol 13:247-251PubMedCrossRef ...
Membrane transport protein: ion channels (TC 1A). Ca2+: Calcium channel. Ligand-gated. *Inositol trisphosphate receptor *1 ... Gap junction beta-1 protein (GJB1), also known as connexin 32 (Cx32) is a transmembrane protein that in humans is encoded by ... affect the peripheral nervous system some cases have been reported in which there is evidence of demyelination of the central ... γ-subunits *γ1. *γ2. *γ3. *γ4. *Cation channels of sperm *1. *2 ...
Subunits of the dimeric channel protein are designated by suffixes (TPC1A, dark blue, TPC1B, pink). The voltage-sensing domain ... 2011). Membrane topology of NAADP-sensitive two-pore channels and their regulation by N-linked glycosylation. J. Biol. Chem. ... membrane potential changes result in movement of the voltage sensor domain, causing the channel gate to open (Catterall, 2010; ... 2005). K+ currents through SV-type vacuolar channels are sensitive to elevated luminal sodium levels. Plant J. 41: 606-614. ...
Furthermore, AβP influences voltage gated Ca2+ channels [44] or inositol triphosphate (IP3) receptor [45]. It is widely ... multilevel and giant pores (~5 nS) and cation (including Ca2+) selectivity. The activity of both channels could be blocked by ... H. Jang, J. Zheng, and R. Nussinov, "Models of beta-amyloid ion channels in the membrane suggest that channel formation in the ... pores which consist of tetrameric and hexameric β-sheet subunits from the observations in NMR [57]. These models are consistent ...
Voltage-gated sodium channels normally consist of an alpha subunit that forms the ion conduction pore and one to two beta ... Sodium channel. transmembrane protein allowing sodium ions in and out. Sodium channels are integral membrane proteins that form ... heart, skeletal muscle, central and peripheral neurons. none known Ligand-gated sodium channels Ligand-gated sodium channels ... "On the structural basis for size-selective permeation of organic cations through the voltage-gated sodium channel. Effect of ...
  • These channels, which function at neuron-neuron and neuron-smooth muscle junctions, may play roles in the control of blood pressure and pain sensation. (tcdb.org)
  • In light of the broad range of physiological roles of cation channels, it is not surprising that channel impairment results in a variety of pathophysiological conditions. (aspetjournals.org)
  • S5 and S6 helices are thought to line the inner pore surface, while S1-4 helices have roles in gating and voltage sensing (S4 in particular). (wikipedia.org)
  • Oligomerization, conformational changes, and the consequent neurodegeneration of Alzheimer's β -amyloid protein (A β P) play crucial roles in the pathogenesis of Alzheimer's disease (AD). (hindawi.com)
  • Our findings suggest important physiological roles of heat-induced variation in Kv channel activities. (elifesciences.org)
  • The voltage sensitivity of this channel is due to positive amino acids located at every third position. (bionity.com)
  • The characterization of distinct δ-ENaC splice variants may explain the diverse cation selectivity and amiloride sensitivity of native ENaC in the lung. (physiology.org)
  • Following an evaluation of this pipeline (MuSICC), which demonstrated a classification sensitivity of 95.2 % and accuracy of 70.5 % for known ion channels, we applied it to effectively identify and classify ion channels in selected parasitic flatworms. (biomedcentral.com)
  • Mammalian BK channels are characterized by their high sensitivity to blockade by iberiotoxin (IbTx) and charybdotoxin. (epfl.ch)
  • Here we report that the homologous voltage-gated potassium (Kv) channels also exhibit high temperature sensitivity comparable to that of TRPV1, which is detectable under specific conditions when the voltage sensor is functionally decoupled from the activation gate through either intrinsic mechanisms or mutations. (elifesciences.org)
  • Therefore, high temperature sensitivity is intrinsic to both TRP and Kv channels. (elifesciences.org)
  • instead, non-obligatory allosteric gating permits the intrinsic heat sensitivity to drive channel activation, allowing temperature-sensitive TRP channels to function as polymodal nociceptors. (elifesciences.org)
  • Instead, as these TRP ion channels do not require other parts of the protein to move in order to open the channel, they can be activated by their own inherent sensitivity to heat. (elifesciences.org)
  • The stimulus used to activate connexin hemichannels is removal of divalent cations, a treatment long known to enhance P2X 7 R sensitivity to agonists ( 49 ). (physiology.org)
  • KCNQ potassium channels modulate sensitivity of skin D-hair mechanoreceptors. (mdc-berlin.de)
  • In addition, a heteromeric association between this member and acid-sensing (proton-gated) ion channel 3 has been observed to co-assemble into proton-gated channels sensitive to gadolinium. (genecards.org)
  • When the α subunit protein is expressed by a cell, it is able to form channels which conduct Na + in a voltage-gated way, even if β subunits are not expressed. (bionity.com)
  • The inactivation is removed when the membrane potential of the cell repolarizes following the falling phase of the action potential. (bionity.com)
  • Furthermore potassium channels are found in most cell types and control a wide variety of cell functions. (wikipedia.org)
  • Inwardly rectifying potassium channel - passes current (positive charge) more easily in the inward direction (into the cell). (wikipedia.org)
  • Two types of calcium channels in single smooth muscle cells from rabbit ear artery studied with whole-cell and single-channel recordings. (springer.com)
  • Some of these channels are opened when the voltage across the cell membrane changes. (thefreelibrary.com)
  • Fairey E, Bottein Dechraoui M, Sheets M, Ramsdell J. Modification of the cell based assay for brevetoxins using human cardiac voltage dependent sodium channels expressed in HEK-293 cells. (labome.org)
  • The expression of voltage dependent sodium channels in HEK cells is anticipated to provide enhanced performance for cell-based detection of toxins for drug and natural product discovery, biomonitoring and environmental monitoring. (labome.org)
  • In many eukaryotic cells, cytokinesis is driven by a contractile actomyosin ring, which forms at the site of cell division and drives furrow ingression [3]. (ovarian-cancersymptoms.com)
  • While NAADP-induced Ca 2+ -release has been found in many tissues and cell types, the molecular identity of the channel(s) conferring this release remained elusive so far. (springer.com)
  • Gap junction beta-1 protein is a member of the gap junction connexin family of proteins that regulates and controls the transfer of communication signals across cell membranes , primarily in the liver and peripheral nervous system . (wikipedia.org)
  • In normal circumstances this protein is located in the cell membrane of Schwann cells and oligodendrocytes , specialised cells of the nervous system. (wikipedia.org)
  • Typically the GJB1 protein forms channels through the myelin to the internal Schwann cell or oligodendrocyte, allowing effective transportation and communication. (wikipedia.org)
  • This sequential depolarisation and repolarisation of the cell membrane is the fundamental basis of the action potential. (bmj.com)
  • A sodium channel in a cell membrane whose opening is governed by the membrane potential. (epfl.ch)
  • The membrane surrounding a cell that separates the cell from its external environment. (epfl.ch)
  • The somata or cell bodies of both nociceptive and non-nociceptive sensory afferents lie in the dorsal root ganglia (DRG), and their central terminals synapse in the superficial spinal dorsal horn. (biologists.org)
  • Calmodulin is a calcium binding protein that plays a role in signaling pathways, cell cycle progression and proliferation. (nih.gov)
  • Along with the changes in cell volume and cation content, accumulation of Ca 2+ was shown to facilitate intercellular adhesion ( 60 ). (physiology.org)
  • This research elaborates the cell components of the NMJ as well as proteins involved supported by scientific research articles which are synthesised within the text. (edu.au)
  • Notably, during T EM cell activation, the number of K v 1.3 channels on the cell membrane dramatically increases. (biomedcentral.com)
  • 00:04:08.06 and they change the membrane potential across the cell, 00:04:11.25 as shown here, 00:04:13.05 in phase one of the action potential. (ibiology.org)
  • 00:04:17.23 and we say the cell membrane is depolarized. (ibiology.org)
  • Bruce, how many channels does it take to kill a cell? (alzforum.org)
  • If the voltage changes by a large enough amount, an all-or-none electrochemical pulse called an action potential is generated and this change in cross-membrane potential travels rapidly along the cell's axon, and activates synaptic connections with other cells when it arrives. (th.ai)
  • Many of these protein toxins have evolved to interact with functionally important domains of ion channels that are freely accessible to water on the external side of the cell membrane, implying that toxin-channel recognition takes place in an aqueous environment. (elifesciences.org)
  • However, paxilline is a lipophilic small molecule that blocks all KCa1.1 channels found in major organs, regardless of channel subunit composition [ 13 - 15 ], and can cross cell membranes as well as the blood-brain barrier. (biomedcentral.com)
  • As Bruce Alberts said in 1998, the biology of the future was going to be the study of molecular machines: the entire cell can be viewed as a factory that contains an elaborate network of interlocking assembly lines, each of which is composed of a set of large protein machines. (theologyonline.com)
  • Western Blot analysis demonstrated quantitative reduction of mutant protein in VHL-associated tumors (renal cell carcinoma [86% to 93%] and hemangioblastoma [73% to 85%]), but messenger RNA expression remained at normal physiologic levels. (jaoa.org)
  • Western blot analysis revealed that mutant VHL protein products retain the fundamental function as an E3 ligase to degrade hypoxia inducible factor (HIF) in stable transfections of 786-0 cells, a VHL-deficient cell line. (jaoa.org)
  • In this study, we used a combination of cell surface assay, bioluminescence resonance energy transfer (BRET), bimolecular fluorescence complementation (BiFC), and biochemical approaches to analyze the interactions existing between P2X subunits. (jneurosci.org)
  • Communication among cells via direct cell-cell contact by connexin gap junctions, or between cell and extracellular environment via pannexin channels or connexin hemichannels, is a key factor in cell function and tissue homeostasis. (biomedcentral.com)
  • LRRC8/VRAC anion channels enhance β-cell glucose sensing and insulin secretion. (mdc-berlin.de)
  • The alpha subunits - such as Nav1.9 - are organized in four homologous domains (I-IV), each of which contain six transmembrane alpha helices (S1-S6) and an additional pore loop located between the S5 and S6 segments (Fig. 1 in Catterall ). (epfl.ch)
  • The six alpha subunits form a central wheel in the assembly, and the beta subunits form domes on the top and bottom of the wheel, creating six reaction chambers within which each ACP can reach the six active sites through surprisingly modest movements. (theologyonline.com)
  • In the context of investigating ion transport across the membrane of RBCs, especially in low ionic strength media, the existence of ion transport dependent on the membrane potential was reported for the first time approximately 50 years ago ( Donlon and Rothstein, 1969 ). (frontiersin.org)
  • Some of these effects are observed in the absence of the beta subunit, whereas, in other cases, the co-expression of beta is required. (thefullwiki.org)
  • Expression of the NMDARs subunits was assessed in erythroid progenitors during ex vivo erythropoiesis and in circulating human RBCs using quantitative PCR and flow cytometry. (physiology.org)
  • A heterologous expression system was developed to examine molecular aspects of the α and β subunits of the CNG channel. (ubc.ca)
  • Expression in mammalian cells helped resolve confusion regarding the JVL of the rod CNG channel a subunit. (ubc.ca)
  • Heterologous expression of the β subunit cDNA yielded a 240 kDa protein, positively identifying the 240 kDa protein in ROS which co-purifies with the a subunit as the CNG β subunit. (ubc.ca)
  • Construction and expression of a truncated form of the (3 subunit demonstrated that it is the glutamic acidrich N-terminal portion of the (3 subunit that is responsible for its anomalous migration on an SDS gel. (ubc.ca)
  • Co-expression of both subunits in mammalian cells indicated that the 3 subunit was not responsible for the processing of the α subunit. (ubc.ca)
  • To do this, we use a combination of quantitative behavioral analysis, genetics, in vivo electrophysiology, and heterologous expression of ion channels. (stanford.edu)
  • Eag channels in view of their restricted expression in normal tissue may emerge as novel tumour biomarkers. (biomedcentral.com)
  • In recent years, expression of several K + channel subtypes has been described in a plethora of malignancies. (biomedcentral.com)
  • Several voltage-gated K+ channel subunits comprising six transmembrane segments and a single pore domain (Kv1.2, Kv1.5, Kv2.1, Kv3.1, Kv3.3, Kv4.2 and Kv9.3) are reversibly blocked by hypoxia when expressed in heterologous expression systems. (antibody-antibodies.com)
  • The β subunit expression by FLS was assessed by quantitative reverse transcription polymerase chain reactions, Western blotting, and patch-clamp electrophysiology combined with pharmacological agents. (biomedcentral.com)
  • FLS were sorted by flow cytometry on the basis of their CD44 expression level for comparison of their invasiveness and with their expression of KCa1.1 α and β subunits. (biomedcentral.com)
  • β1 and β3 subunit expression was reduced with small interfering RNA (siRNA) to assess their specific role in KCa1.1α expression and function and in FLS invasiveness. (biomedcentral.com)
  • Aldosterone-induced K(+) secretion occurs via increased expression of luminal BK channels . (epfl.ch)
  • In addition, chronic activity blockade reduces total potassium current, as well as protein expression and current of voltage-gated K v 1 and K v 7 potassium channels, which are critical regulators of action potential firing. (biomedcentral.com)
  • The α-subunit has four repeat domains, labelled I through IV, each containing six membrane-spanning segments, labelled S1 through S6. (wikipedia.org)
  • The inner portion (i.e., more cytoplasmic) of the pore is formed by the combined S5 and S6 segments of the four domains. (wikipedia.org)
  • Each domain contains six probable transmembrane α-helices (termed segments S1-S6) with a membrane-reentrant loop between the S5 and S6 segments ( Guy and Seetharamulu, 1986 ). (aspetjournals.org)
  • The pore loops line the outer, narrow entry to the pore, whereas the S5 and S6 segments line the inner, wider exit from the pore. (epfl.ch)
  • Additionally, the background K+ channel subunit TASK-1, which comprises four transmembrane segments and two pore domains, is also involved in both oxygen- and acid-sensing in peripheral chemoreceptors. (antibody-antibodies.com)
  • The number of functionally distinct channels in native tissues is further increased by heteromultimeric assembly of potassium channel α-subunits with other α- and β-subunits and other modifications such as alternative splicing of mRNAs, glycosylation, and phosphorylation. (aspetjournals.org)
  • MuSICC provides a practical and effective tool for the identification and classification of ion channels of parasitic flatworms, and should be applicable to a broad range of organisms that are evolutionarily distant from taxa whose ion channels are functionally characterised. (biomedcentral.com)
  • By contributing to the regulation of the action potential duration in cardiac muscle, malfunction of potassium channels may cause life-threatening arrhythmias. (wikipedia.org)
  • Although this modular design has greatly facilitated biophysical and structural studies on individual GluR domains, and suggested conserved mechanisms for iGluR gating, recent work is beginning to reveal unanticipated diversity in the structure, allosteric regulation, and assembly of iGluR subtypes ( Mayer, 2011 ). (tcdb.org)
  • Oxidant- and antioxidant-mediated mechanisms (that is, redox regulation) of ion channels are areas of intense research. (physiology.org)
  • Significant progress has been made in our understanding of redox regulation of ion channels since the last Experimental Biology report in 2003. (physiology.org)
  • 1 ) identification of nonphagocytic NADPH oxidases as sources of regulated reactive species (RS) production in epithelia, 2 ) an understanding that excessive treatment with antioxidants can result in greater oxidative stress, and 3 ) characterization of novel RS signaling pathways that converge upon ion channel regulation. (physiology.org)
  • 20 1.1.6 Structure, function and regulation of sodium and potassium channels and transporter in the ASDN. (spotidoc.com)
  • It is a co-factor in multiple enzymatic reactions, including those involving energy metabolism and DNA and protein synthesis, and it participates in the regulation of ion channels. (asnjournals.org)
  • 3 This last process is where the greatest regulation occurs and consequently is the major focus of this review. (asnjournals.org)
  • In the mammalian pancreas, Zn 2+ is essential for the correct processing, storage, secretion, and action of insulin in beta (β)-cells. (springer.com)
  • However, Yang and Zheng now report that similar ion channels, which open in response to changes in the voltage that exists across a cell's membrane, are also sensitive to changes in temperature. (elifesciences.org)
  • Alternatively four related but not identical protein subunits may associate to form heterotetrameric complexes with pseudo C4 symmetry. (wikipedia.org)
  • Many of these protein complexes are multisubunit with a large subunit serving the primary ATPase and ion translocation functions. (tcdb.org)
  • Deciphering the quaternary structure of such protein complexes is an arduous task and usually requires the combination of multiple approaches. (jneurosci.org)
  • Reconstitution after purification and subunit characterization. (springer.com)
  • 1989) of what is now known to be the CNG channel α subunit facilitated its molecular characterization. (ubc.ca)
  • We report the first comprehensive characterization of the membrane protein machinery of biotechnologically relevant anaerobic gut fungi. (biomedcentral.com)
  • Together with the Port-a-Patch, Nanion´s state-of-the-art automated patch clamp platform, the efficiency of characterization of pore-forming peptides (and other ionophores from natural sources) in artificial bilayers has greatly increased. (nanion.de)
  • The system presented here will be useful to further define CNG α and β subunit interactions and to carry out structure-function studies on the channel using a biochemical efflux assay. (ubc.ca)
  • We also provide improved structures of TRPV1 with and without the toxin bound, and investigate the interactions of DkTx with the channel and membranes. (elifesciences.org)
  • The relationships between the amino acid sequences of various human proteins that feature one or more VSD motifs are represented as a circular phylogenic tree. (frontiersin.org)
  • Protein kinases are enzymes that transfer a phosphate group from a phosphate donor onto an acceptor amino acid in a substrate protein. (ovarian-cancersymptoms.com)
  • The tetrodotoxin resistant NaV1.5, NaV1.8, and NaV1.9 are closely related ( see phylogenetic tree, fig. 2B in Catterall ), and their amino acid sequences are greater than 64% identical to those of the four sodium channels encoded on chromosome 2 (the highly tertodotoxin sensitive NaV1.1, NaV1.2, NaV1.3, and NaV1.7). (epfl.ch)
  • The membrane potential of airway and alveolar epithelial cells has been measured in pneumocytes and range between −24 and −63 mV ( 10 , 12 , 31 , 32 , 34 , 65 , 73 ). (physiology.org)
  • In the lung, amiloride-sensitive epithelial Na + channels (ENaC), composed of α-, β-, and γ-subunits, have been identified as the major contributor of net salt and water reabsorption. (physiology.org)
  • Intercellular communication between cells is realized through gap junction channels formed by connexins (Cx). (biomedcentral.com)
  • In the current review, we will highlight the most recent literature on the role of connexins in cancer, and introduce the more recently discovered pannexin channels and their proposed function in different cancer types. (biomedcentral.com)
  • Cancer was one of the first pathologies found to be associated with gap junction channel impairment, and connexins have long been shown to possess tumor suppressive function [ 35 ]. (biomedcentral.com)
  • Recently, Arispe has published evidence that specific regions of the peptide seem to line the pore (see Arispe, 2004 ). (alzforum.org)
  • Moreover, evidence for such a role of connexin hemichanels is heavily dependent on use of compounds known to block intercellular gap junction channels, which have recently been shown to also block the P2X 7 R-mediated uptake of dye molecules ( 46 ). (physiology.org)
  • Venom toxins are invaluable tools for exploring the structure and mechanisms of ion channels. (elifesciences.org)
  • Thus, these small proteins are invaluable tools for investigating ion-channel structures and operational mechanisms. (elifesciences.org)
  • We explored the pharmacological action of compounds known to block gap junctions on Panx1 channels activated by the P2X 7 R and the mechanisms involved in the interaction between these two proteins. (physiology.org)