Sea anemone neurotoxin is the name given to neurotoxins produced by sea anemones with related structure and function. Sea anemone neurotoxins can be divided in two functional groups that either specifically target the sodium channel or the potassium channel. A number of proteins belong to the sodium channel toxin family, including ''

calitoxin Calitoxin, also known as CLX, is a sea anemone neurotoxin produced by the sea anemone ''Calliactis parasitica''. It targets crabs and octopuses, among other invertebrates. Two isoforms (CLX-1 and CLX-2) have been identified, both of which ...

'' and '' anthopleurin''. The neurotoxins bind specifically to the

sodium channel 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 chann ...

, thereby delaying its inactivation during signal transduction, resulting in strong stimulation of mammalian cardiac muscle contraction. Calitoxin 1 has been found in neuromuscular preparations of

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...

s, where it increases transmitter release, causing firing of the

axon An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action p ...

s. Three disulfide bonds are present in this protein. This family also includes the

antihypertensive Antihypertensives are a class of drugs that are used to treat hypertension (high blood pressure). Antihypertensive therapy seeks to prevent the complications of high blood pressure, such as stroke and myocardial infarction. Evidence suggests tha ...

and

antiviral protein Antiviral proteins are proteins that are induced by human or animal cells to interfere with viral replication. These proteins are isolated to inhibit the virus from replicating in a host's cells and stop it from spreading to other cells. The Pok ...

s BDS-I () and BDS-II () expressed by '' Anemonia viridis'' (previously '' Anemonia sulcata)''. BDS-I is organised into a triple-stranded antiparallel beta-sheet, with an additional small antiparallel beta-sheet at the N-terminus. Both peptides are known to specifically block the Kv3.4 potassium channel, and thus bring about a decrease in blood pressure. Moreover, they inhibit the cytopathic effects of mouse hepatitis virus strain MHV-A59 on mouse liver cells, by an unknown mechanism. The potassium channel toxin family include

kaliseptine Kaliseptine (AsKS) is a neurotoxin which can be found in the snakelocks anemone ''Anemonia viridis''. It belongs to a class of sea anemone neurotoxins that inhibits voltage-gated potassium channels. Etymology “Kali” is derived from the Latin ...

and kalicludines, and was also isolated from '' Anemonia viridis''.

References

Protein domains * Peripheral membrane proteins Neurotoxins {{membrane-protein-stub

See also

References