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Ergtoxin
Ergtoxin (CnErg1, CnErgTx1, ErgTx, ErgTx1, ɣ-KTx1.1) is a toxin from the venom of the Mexican scorpion ''Centruroides noxius''. This toxin targets hERG (human Ether- à -go-go-Related Gene) potassium channels. Sources The toxin is derived from the venomous gland of the Mexican scorpion ''Centruroides noxius'', Chemistry Based on primary sequence alignment, there are 27 different ɣ-KTx's, all of which belong to the larger group of scorpion short chain toxins that affect K+ channels (KTx). The first member of this ɣ-KTx family, Ergtoxin (ɣ-KTx1.1), is a polypeptide composed of 42 amino acid residues. It has the following one-letter amino acid code: DRDSCVDKSRCAKYGYYQECQDCCKNAGHNGGTCMFFKCKCA. The Ergtoxin sequence contains four disulfide bridges between Cys5-Cys23, Cys11-Cys34, Cys20-Cys39 and Cys24-Cys41 and has a molecular mass of 4730.8 ± 0.4 Da. Ergtoxin displays two clusters of amino acids, one hydrophobic and one hydrophilic. Its structure is stabilized by five ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centruroides Noxius
''Centruroides noxius'' is a species of scorpion native to Mexico. Description and behavior This species grows from 3.5 to 5 cm in length, its body is dark in color, usually black or brown, and its legs and pedipalps are generally light, this species does not have a specific color pattern since it can be found with other colors. Since most scorpions are nocturnal, they usually hide in litter and debris, or in loose barks of trees and bushes, it is mostly terrestrial, but it has also been reported to rise on rough surfaces. Distribution and habitat This species is native to Mexico, in the states of Nayarit, but also in Jalisco and Sinaloa. it is also found in other Latin American countries, such as Chile, but it is not known how it got there. It is mainly found in dry arid places, areas of limited vegetation, in sandy and rocky soil and sometimes in human dwellings, it has been reported close to sea level, with 500 m elevation. Reproduction Mating lasts about 10 minu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centruroides Gracilis
''Centruroides gracilis'' is a species of scorpion in the family Buthidae, the bark scorpions. Its common names include Florida bark scorpion, brown bark scorpion, and slender brown scorpion.Rein, J. O''Centruroides gracilis''.The Scorpion Files. Norwegian University of Science and Technology, Trondheim. 2012.Muma, M. H. (1967)Scorpions, whip scorpions and wind scorpions of Florida.In: ''Arthropods of Florida and Neighboring Areas, Volume 4.'' Division of Plant Industry. Florida Department of Agriculture. In Cuba it is known as ''alacran prieto'' ("dusky scorpion") and ''alacran azul'' ("blue scorpion"). Contrary to one of its common names, it is not actually native to Florida in the United States. It is native to northern parts of the middle Americas, including Mexico, Guatemala, Belize, and Honduras. It is present in other parts as an introduced species, including Cuba, Panama, Colombia, Ecuador, Jamaica,Teruel, R. (2008)Confirmation of the occurrence of ''Centruroides gracilis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotoxins
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 membrane, or c ... [...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] |
SK-OV-3
SK-OV-3 (also known as SKOV-3; SK.OV.3; SKOV3; Skov3 and SKO3) is an ovarian cancer cell line derived from the ascites of a 64-year-old Caucasian female with an ovarian serous cystadenocarcinoma. The SK-OV-3 cell line is also hypodiploid, with a modal number of chromosomes of 43 (range 42-45), occurring in 63.3% of cells. SK-OV-3 are positive for many of the antigens used to identify cancers of epithelial origin in clinical practice, including vimentin (VIM), high molecular weight cytokeratin (HMWK), low molecular weight cytokeratin (LMWK), epithelial membrane antigen (EMA) and leucocyte common antigen (LCA). Use in Research Early work by Fogh, J. in 1986 showed that SK-OV-3 cells do not express the MUC16 (CA125) mucin antigen (that later became the most frequently used biomarker for ovarian cancer detection) and also showed using dose-response curves that SK-OV-3 were platinum sensitive. It was subsequently shown that ectopic expression of the MUC16 C-terminal domain in SK-OV-3 cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Proliferation
Cell proliferation is the process by which ''a cell grows and divides to produce two daughter cells''. Cell proliferation leads to an exponential increase in cell number and is therefore a rapid mechanism of tissue growth. Cell proliferation requires both cell growth and cell division to occur at the same time, such that the average size of cells remains constant in the population. Cell division can occur without cell growth, producing many progressively smaller cells (as in cleavage of the zygote), while cell growth can occur without cell division to produce a single larger cell (as in growth of neurons). Thus, cell proliferation is not synonymous with either cell growth or cell division, despite the fact that these terms are sometimes used interchangeably. Stem cells undergo cell proliferation to produce proliferating "transit amplifying" daughter cells that later differentiate to construct tissues during normal development and tissue growth, during tissue regeneration aft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
K+ Channels
K, or k, is the eleventh letter in the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''kay'' (pronounced ), plural ''kays''. The letter K usually represents the voiceless velar plosive. History The letter K comes from the Greek letter Κ (kappa), which was taken from the Semitic kaph, the symbol for an open hand. This, in turn, was likely adapted by Semitic tribes who had lived in Egypt from the hieroglyph for "hand" representing /ḏ/ in the Egyptian word for hand, ⟨ ḏ-r-t⟩ (likely pronounced in Old Egyptian). The Semites evidently assigned it the sound value instead, because their word for hand started with that sound. K was brought into the Latin alphabet with the name ''ka'' /kaː/ to differentiate it from C, named ''ce'' (pronounced /keː/) and Q, named ''qu'' and pronounced /kuː/. In the earliest Latin inscriptions, the letters C, K and Q were all used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disulfide Bridges
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] |
Centruroides Exilicauda
''Centruroides exilicauda'', the Baja California bark scorpion, is a species of bark scorpion found in Baja California. It is closely related to the Arizona bark scorpion (''Centruroides sculpturatus''), but is not considered dangerous. Previously only distinguished by geographic range, the two variants were classified in 1980 as the same species. Subsequently, differences in venom toxicity were recorded, and in 2004, DNA analysis showed them to be separate species. The Baja California bark scorpion is a slender, long-tailed scorpion, and although it is typically sand-colored it appears in darker colors. Background The Baja California Bark Scorpion is a scorpion that belongs to the '' Centruroides'' genus and ''exilicauda'' species and is one of the 529 species of scorpions around today and one of the 41 bark species of scorpions. They are native to the Western parts of North America, including Baja California, California, Arizona, and New Mexico. They have also been ... [...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] |
Centruroides Sculpturatus
:''The striped bark scorpion and the closely related Baja California bark scorpion are also called bark scorpions.'' The Arizona bark scorpion (''Centruroides sculpturatus'', once included in '' Centruroides exilicauda'') is a small light brown scorpion common to the Sonoran Desert in the southwestern United States and northwestern Mexico. An adult male can reach 8 cm in length (3.14 inches), while a female is slightly smaller, with a maximum length of 7 cm (2.75 inches). Predators Arizona bark scorpions are eaten by a wide variety of animals such as pallid bats, birds (especially owls), reptiles, and other vertebrates. Some examples include spiders, snakes, peccaries, rodents, and other scorpions. Development, pesticides and collecting scorpions for research or the pet trade also reduces the bark scorpion population. The painful and potentially deadly venom of Arizona bark scorpions has little effect on grasshopper mice. Scientists have found the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centruroides Elegans
''Centruroides elegans'' is a scorpion species in the genus '' Centruroides'' found in Mexico. References External links ''Centruroides elegans'' photo on www.flickr.com''Centruroides elegans'' at insectoid.info elegans Scorpions described in 1876 Endemic scorpions of Mexico {{Scorpion-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
