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AmmTX3
AmmTX3, produced by ''Androctonus mauretanicus'', is a scorpion toxin of the α-KTX15 subfamily. The toxin is known for its ability to act as a specific Kv4 channel blocker, and thereby reducing the A-type potassium current through this channel. Etymology and source AmmTX3 (α-KTX15.3) is a peptide that can be isolated from the venom of ''Androctonus mauretanicus''. ''Androctonus mauretanicus'' is a fat-tailed scorpion with its origins in North Africa. Chemistry AmmTX3 has a molecular mass of 3823.5 Da and consists of a single chain of 37 amino acid residues. These residues are cross-linked by three disulfide bridges. The toxin contains the dyad characteristic (K27 and Y36) that is found in pore-blocking potassium channel-specific toxins, and is therefore likely to act as a pore blocker. AmmTX3 is a member of the α-KTX15 subfamily. This subfamily currently exists of six very homologous peptides, originating from scorpion venom: Aa1, AaTX1, AaTX2, AmmTX3, BmTx3 and Discr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scorpion Toxin
Scorpion toxins are proteins found in the venom of scorpions. Their toxic effect may be mammal- or insect-specific and acts by binding with varying degrees of specificity to members of the Voltage-gated ion channel superfamily; specifically, voltage-gated sodium channels, voltage-gated potassium channels, and Transient Receptor Potential (TRP) channels. The result of this action is to activate or inhibit the action of these channels in the nervous and cardiac organ systems. For instance, α-scorpion toxins MeuNaTxα-12 and MeuNaTxα-13 from ''Mesobuthus eupeus'' are neurotoxins that target voltage-gated Na+ channels (Navs), inhibiting fast inactivation. ''In vivo'' assays of MeuNaTxα-12 and MeuNaTxα-13 effects on mammalian and insect Navs show differential potency. These recombinants (MeuNaTxα-12 and MeuNaTxα-13) exhibit their preferential affinity for mammalian and insect Na+ channels at the α-like toxins' active site, site 3, in order to inactivate the cell membrane depolari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androctonus
Fattail scorpion or fat-tailed scorpion is the common name given to scorpions of the genus ''Androctonus'', one of the most dangerous groups of scorpion species in the world.Hendrixson, B. E. 2006. Buthid scorpions of Saudi Arabia, with notes on other families (Scorpiones: Buthidae, Liochelidae, Scorpionidae). In W. Büttiker, F. Krupp, I. Nader & W. Schneider (eds.), Fauna of Arabia (pp. in press, ~100 pages). Basel, Switzerland: Karger Libri. The genus was first described in 1828 by Christian Gottfried Ehrenberg. They are found throughout the semi-arid and arid regions of the Middle East and Africa. They are moderate sized scorpions, attaining lengths of 10 cm (just under 4 in). Their common name is derived from their distinctly fat metasoma, or tail, while the Latin name originates from Greek and means "man killer". Their venom contains powerful neurotoxins and is especially potent. Stings from ''Androctonus'' species are known to cause several human deaths each ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scorpion Toxin
Scorpion toxins are proteins found in the venom of scorpions. Their toxic effect may be mammal- or insect-specific and acts by binding with varying degrees of specificity to members of the Voltage-gated ion channel superfamily; specifically, voltage-gated sodium channels, voltage-gated potassium channels, and Transient Receptor Potential (TRP) channels. The result of this action is to activate or inhibit the action of these channels in the nervous and cardiac organ systems. For instance, α-scorpion toxins MeuNaTxα-12 and MeuNaTxα-13 from ''Mesobuthus eupeus'' are neurotoxins that target voltage-gated Na+ channels (Navs), inhibiting fast inactivation. ''In vivo'' assays of MeuNaTxα-12 and MeuNaTxα-13 effects on mammalian and insect Navs show differential potency. These recombinants (MeuNaTxα-12 and MeuNaTxα-13) exhibit their preferential affinity for mammalian and insect Na+ channels at the α-like toxins' active site, site 3, in order to inactivate the cell membrane depolari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A-type Potassium Channel
Voltage-gated potassium channels (VGKCs) are transmembrane channels specific for potassium and sensitive to voltage changes in the cell's membrane potential. During action potentials, they play a crucial role in returning the depolarized cell to a resting state. Classification Alpha subunits Alpha subunits form the actual conductance pore. Based on sequence homology of the hydrophobic transmembrane cores, the alpha subunits of voltage-gated potassium channels are grouped into 12 classes. These are labeled Kvα1-12. The following is a list of the 40 known human voltage-gated potassium channel alpha subunits grouped first according to function and then subgrouped according to the Kv sequence homology classification scheme: Delayed rectifier slowly inactivating or non-inactivating *Kvα1.x - Shaker-related: Kv1.1 (KCNA1), Kv1.2 (KCNA2), Kv1.3 (KCNA3), Kv1.5 (KCNA5), Kv1.6 (KCNA6), Kv1.7 ( KCNA7), Kv1.8 (KCNA10) *Kvα2.x - Shab-related: Kv2.1 (KCNB1), Kv2.2 (KCNB2) *Kvα3.x - ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fat-tailed Scorpion
Fattail scorpion or fat-tailed scorpion is the common name given to scorpions of the genus ''Androctonus'', one of the most dangerous groups of scorpion species in the world.Hendrixson, B. E. 2006. Buthid scorpions of Saudi Arabia, with notes on other families (Scorpiones: Buthidae, Liochelidae, Scorpionidae). In W. Büttiker, F. Krupp, I. Nader & W. Schneider (eds.), Fauna of Arabia (pp. in press, ~100 pages). Basel, Switzerland: Karger Libri. The genus was first described in 1828 by Christian Gottfried Ehrenberg. They are found throughout the semi-arid and arid regions of the Middle East and Africa. They are moderate sized scorpions, attaining lengths of 10 cm (just under 4 in). Their common name is derived from their distinctly fat metasoma, or tail, while the Latin name originates from Greek and means "man killer". Their venom contains powerful neurotoxins and is especially potent. Stings from ''Androctonus'' species are known to cause several human death ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disulfide
In biochemistry, a disulfide (or disulphide in British English) refers to a functional group with the structure . The linkage is also called an SS-bond or sometimes a disulfide bridge and is usually derived by the coupling of two thiol groups. In biology, disulfide bridges formed between thiol groups in two cysteine residues are an important component of the secondary and tertiary structure of proteins. ''Persulfide'' usually refers to compounds. In inorganic chemistry disulfide usually refers to the corresponding anion (−S−S−). Organic disulfides Symmetrical disulfides are compounds of the formula . Most disulfides encountered in organo sulfur chemistry are symmetrical disulfides. Unsymmetrical disulfides (also called heterodisulfides) are compounds of the formula . They are less common in organic chemistry, but most disulfides in nature are unsymmetrical. Properties The disulfide bonds are strong, with a typical bond dissociation energy of 60 kcal/mol (251&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BmTx3
BmTx3 is a neurotoxin, which is a component of the venom of the scorpion ''Buthus Martensi'' Karsch. It blocks A-type potassium channels in the central nervous system and hERG-channels in the heart. Source/Isolation BmTx3 was originally purified from the venom of the Chinese scorpion, ''Buthus Martensi'' Karsch. BmTx3 is a “short-chain” peptide like other potassium channel blockers in the scorpion venom and added to the phylogenetic tree in the subfamily α-KTx15. Its 3D structure has not yet been elucidated, but based on sequence similarity it likely resembles the 3D structure of BmTx1 or Discrepin. Biochemistry BmTx3 consists of an α-helix and two β-sheet segments cross-linked by three disulfide bridges (Cs-α/β motif). It is a short chain peptide with a molecular mass of 3751.6 Da; it consists of 37 amino acids. Target BmTx3 is the first toxin from the scorpion α-KTx subfamily 15 with two functional faces. As all α-KTx peptides, BmTx3 blocks A-type (IA) potassium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discrepin
Discrepin (α-KTx15.6) is a peptide from the venom of the Venezuelan scorpion ''Tityus discrepans''. It acts as a neurotoxin by irreversibly blocking A-type voltage-dependent K+-channels. Etymology and source Discrepin is named after its source: a Venezuelan scorpion called ''Tityus discrepans''. Its systematic number is α-KTx15.6. Chemistry The subfamily α-KTx15 consists of 6 toxins. The first five toxins of this subfamily are very much alike, but discrepin only shares 50% amino acid homology with other members of this subfamily. Discrepin contains 38 amino acid residues. It has a polyglutamic acid at its N-terminal region. Discrepin has the α and β folds that are characteristic of scorpion toxins. It consists of one α-helix and three β-sheet helix strands. The α-helix is formed from amino acid Ser11 until Arg21. The three antiparallel β-sheets are formed from amino acid Ile2 until Lys7, Ala27 until Cys29 and Arg33 until Cys36. Target Discrepin blocks voltage-gated Sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DPP6
Dipeptidyl aminopeptidase-like protein 6 is a protein that in humans is encoded by the ''DPP6'' gene. This gene encodes a single-pass type II membrane protein that is a member of the S9B family in clan SC of the serine proteases. This protein has no detectable protease activity, most likely due to the absence of the conserved serine residue normally present in the catalytic domain of serine proteases. However, it does bind specific voltage-gated potassium channels and alters their expression and biophysical properties. Alternate transcriptional splice variants, encoding different isoforms A protein isoform, or "protein variant", is a member of a set of highly similar proteins that originate from a single gene or gene family and are the result of genetic differences. While many perform the same or similar biological roles, some isof ..., have been characterized. References Further reading * * * * * * * * * * * * * * * * {{gene-7-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DPP10
Inactive dipeptidyl peptidase 10 is a protein that in humans is encoded by the ''DPP10'' gene. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. Function This gene encodes a single-pass type II membrane protein that is a member of the S9B family in clan SC of the serine proteases. This protein has no detectable protease activity, most likely due to the absence of the conserved serine residue normally present in the catalytic domain of serine proteases. However, it does bind specific voltage-gated potassium channels and alters their expression and biophysical properties. Clinical significance Mutations in this gene have been associated with asthma and autism spectrum disorders The autism spectrum, often referred to as just autism or in the context of a professional diagnosis autism spectrum disorder (ASD) or autism spectrum condition (ASC), is a neurodevelopmental disorder, neurodevelopmental condition (or conditions) .... R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HERG
hERG (the human '' Ether-à-go-go''-Related Gene) is a gene () that codes for a protein known as Kv11.1, the alpha subunit of a potassium ion channel. This ion channel (sometimes simply denoted as 'hERG') is best known for its contribution to the electrical activity of the heart: the hERG channel mediates the repolarizing ''I''Kr current in the cardiac action potential, which helps coordinate the heart's beating. When this channel's ability to conduct electrical current across the cell membrane is inhibited or compromised, either by application of drugs or by rare mutations in some families, it can result in a potentially fatal disorder called long QT syndrome. Conversely, genetic mutations that increase the current through these channels can lead to the related inherited heart rhythm disorder Short QT syndrome. A number of clinically successful drugs in the market have had the tendency to inhibit hERG, lengthening the QT and potentially leading to a fatal irregularity of the h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solitary Nucleus
In the human brainstem, the solitary nucleus, also called nucleus of the solitary tract, nucleus solitarius, and nucleus tractus solitarii, (SN or NTS) is a series of purely sensory nuclei (clusters of nerve cell bodies) forming a vertical column of grey matter embedded in the medulla oblongata. Through the center of the SN runs the solitary tract, a white bundle of nerve fibers, including fibers from the facial, glossopharyngeal and vagus nerves, that innervate the SN. The SN projects to, among other regions, the reticular formation, parasympathetic preganglionic neurons, hypothalamus and thalamus, forming circuits that contribute to autonomic regulation. Cells along the length of the SN are arranged roughly in accordance with function; for instance, cells involved in taste are located in the rostral part, while those receiving information from cardio-respiratory and gastrointestinal processes are found in the caudal part. Inputs * Taste information from the facial nerve via t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
