To use all functions of this page, please activate cookies in your browser.
my.bionity.com
With an accout for my.bionity.com you can always see everything at a glance – and you can configure your own website and individual newsletter.
- My watch list
- My saved searches
- My saved topics
- My newsletter
Omega-grammotoxin SIAOmega-grammotoxin SIA is a protein toxin that inhibits P, Q and N voltage-gated calcium channels (Ca2+ channels) in neurons. Additional recommended knowledge
SourceThe source of omega-grammotoxin SIA is the venom of a tarantula spider (Grammostola rosea). ChemistryAmino Acid Sequence: Asp-Cys-Val-Arg-Phe-Trp-Gly-Lys-Cys-Ser-Gln-Thr-Ser-Asp-Cys-Cys-Pro-His-Leu-Ala-Cys-Lys-Ser-Lys-Trp-Pro-Arg-Asn-Ile-Cys-Val-Trp-Asp-Gly-Ser-Val[1] Molecular Formula: C177H268N52O50S6[1] Omega-grammotoxin SIA can be purified from Grammostola rosea venom by reverse phase high performance liquid chromatography.[2] TargetOmega-Grammotoxin SIA is a 36 amino acid residue protein toxin from spider venom that inhibits P, Q and N-type voltage-gated calcium channels in neurons. It binds to the channels with high affinity (if closed). It also binds to potassium channels but with lower affinity than to the calcium channels.[3] The toxin binding site has high affinity when channels are in closed states and low affinity when channels are activated. (4) Mode of actionIt is believed that omega-grammotoxin SIA inhibits channel function by binding with high affinity to closed, resting states of the channel and that bound toxin makes it more difficult for channels to be opened by depolarization, so much larger depolarizations are required for channel activation.[4] References
|
|
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Omega-grammotoxin_SIA". A list of authors is available in Wikipedia. |