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BotIT6
BotIT6 is a toxin that binds to insect voltage gated sodium channels. It decreases the amplitude of the action potential, leading to paralysis. Etymology and Source BotIT6 is a neurotoxin produced by the common European scorpion, which is also known as the Buthus occitanus tunetanus. It is therefore appropriately named buthus occitanus tunetanus insect toxin 6 (BotIT6). Chemistry Structure BotIT6 consists of 62 amino-acids and has an experimentally determined molecular mass of 7260.84 Da. Family BotIT6 belongs to the Buthidae neurotoxin family. The toxins can be divided into groups based on their target animal. BotIT6 is targeted at insects. Toxins directed against insects, the main target being the sodium channels, can be divided into four groups, namely excitatory toxins, depressant toxins, α-type toxins and a group affecting both mammals and insects. Each group causes paralysis, albeit via different mechanisms. The BotIT6 has characteristics of depressant, excitatory and � ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BotIT2
BotIT2 is a neurotoxin from the scorpion ''Buthus occitanus tunetanus'', which modifies activation and slows down the deactivation of voltage gated sodium channels. Source and etymology BotIT2 is found in the venom of the scorpion ''Buthus occitanus tunetanus'' (Bot) and hence named Buthus occitanus tunetanus insect toxin 2 (BotIT2). Chemistry Structure The BotIT2 peptide is composed of 60 amino-acids (Fig. 1) and its C-terminal residue contains a free carboxyl group. The molecular mass of BotIT2 is 6919 Da. Family BotIT2 belongs to the Buthidae neurotoxin family. Three main groups are distinguishable in this family: the α-, the β- and the depressant toxins. The BotIT2 has characteristics of all these subgroups. However, BotIT2 is classified as a β-depressant toxin. Homology BotIT2 differs from other scorpion toxins not only in its amino acid sequence, but in its effects on activation kinetics of insect sodium channels as well. Similarities are found between Bot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buthus Occitanus
''Buthus occitanus'', the common yellow scorpion, is a species of scorpion in the family Buthidae. It occurs in the Middle East, North Africa and Europe. ''B. occitanus'' is 60–80 mm in length, has a yellow or yellow-brown color and is venomous producing BotIT6 toxin, but its toxicity varies markedly across its range. This scorpion is often found in dry and hot areas with sparse vegetation, where it hides under stones etc. during daytime. It has also been reported from Mediterranean forests in Spain at altitudes above 1000 meters (with snowfall Snow comprises individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes. It consists of frozen crystalline water throughout ... in the winter). The sting in Europe is painful but with only mild toxic effects, however, in Africa it can be fatal. References Buthidae Animals described in 1789 Scorpions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voltage Gated Sodium Channels
Sodium channels are integral membrane proteins that form ion channels, conducting sodium ions (Na+) through a cell's membrane. They belong to the superfamily of cation channels and can be classified according to the trigger that opens the channel for such ions, i.e. either a voltage-change ("voltage-gated", "voltage-sensitive", or "voltage-dependent" sodium channel; also called "VGSCs" or "Nav channel") or a binding of a substance (a ligand) to the channel ( ligand-gated sodium channels). In excitable cells such as neurons, myocytes, and certain types of glia, sodium channels are responsible for the rising phase of action potentials. These channels go through three different states called resting, active and inactive states. Even though the resting and inactive states would not allow the ions to flow through the channels the difference exists with respect to their structural conformation. Selectivity Sodium channels are highly selective for the transport of ions across cell memb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotoxin
Neurotoxins are toxins that are destructive to nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insultsSpencer 2000 that can adversely affect function in both developing and mature nervous tissue.Olney 2002 The term can also be used to classify endogenous compounds, which, when abnormally contacted, can prove neurologically toxic. Though neurotoxins are often neurologically destructive, their ability to specifically target neural components is important in the study of nervous systems. Common examples of neurotoxins include lead, ethanol (drinking alcohol), glutamate,Choi 1987 nitric oxide, botulinum toxin (e.g. Botox), tetanus toxin,Simpson 1986 and tetrodotoxin. Some substances such as nitric oxide and glutamate are in fact essential for proper function of the body and only exert neurotoxic effects at excessive concentrations. Neurotoxins inhibit neuron control over ion concentrations across the cell memb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buthidae
The Buthidae are the largest family of scorpions, containing about 100 genera and 1339 species as of 2022. A few very large genera ('' Ananteris'', '' Centruroides'', ''Compsobuthus'', or '' Tityus'') are known, but a high number of species-poor or monotypic ones also exist. New taxa are being described at a rate of several new species per year. They have a osmopolitandistribution throughout tropical and subtropical environments worldwide. Together with four other families, the Buthidae make up the superfamily Buthoidea. The family was established by Carl Ludwig Koch in 1837. Around 20 species of medically important (meaning potentially lethal to humans) scorpions are known, and all but one of these (''Hemiscorpius lepturus'') are members of the Buthidae. In dead specimens, the spine beneath the stinger, characteristic for this family, can be observed. List of genera and number of species The following genera are recognised in the family Buthidae: * '' Aegaeobuthus'' Kovar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Action Potential
An action potential occurs when the membrane potential of a specific cell location rapidly rises and falls. This depolarization then causes adjacent locations to similarly depolarize. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and in some plant cells. Certain endocrine cells such as pancreatic beta cells, and certain cells of the anterior pituitary gland are also excitable cells. In neurons, action potentials play a central role in cell-cell communication by providing for—or with regard to saltatory conduction, assisting—the propagation of signals along the neuron's axon toward synaptic boutons situated at the ends of an axon; these signals can then connect with other neurons at synapses, or to motor cells or glands. In other types of cells, their main function is to activate intracellular processes. In muscle cells, for example, an action potential is the first step in the chain of event ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LD50
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a toxin, radiation, or pathogen. The value of LD50 for a substance is the Dose (pharmacology), dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD50 is indicative of increased toxicity. The test was created by J.W. Trevan in 1927. The term semilethal dose is occasionally used in the same sense, in particular with translations of foreign language text, but can also refer to a sublethal dose. LD50 is usually determined by tests on animals such as Laboratory mouse, laboratory mice. In 2011, the U.S. Food and Drug Administration approved alternative methods to LD50 for testing the cosmetic drug Botox without animal tests. Conventions The LD50 is usually expressed as the m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scorpion Toxins
Scorpions are predatory arachnids of the order Scorpiones. They have eight legs, and are easily recognized by a pair of grasping pincers and a narrow, segmented tail, often carried in a characteristic forward curve over the back and always ending with a stinger. The evolutionary history of scorpions goes back 435 million years. They mainly live in deserts but have adapted to a wide range of environmental conditions, and can be found on all continents except Antarctica. There are over 2,500 described species, with 22 extant (living) families recognized to date. Their taxonomy is being revised to account for 21st-century genomic studies. Scorpions primarily prey on insects and other invertebrates, but some species hunt vertebrates. They use their pincers to restrain and kill prey, or to prevent their own predation. The venomous sting is used for offense and defense. During courtship, the male and female grasp each other's pincers and dance while he tries to move her onto his sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
