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ω-Tbo-IT1–New Inhibitor of Insect Calcium Channels Isolated from Spider Venomстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 11 января 2016 г.
- Авторы: Mikov AN, Fedorova IM, Potapieva NN, Maleeva EE, Andreev YA, Zaitsev AV, Kim KK, Bocharov EV, Bozin TN, Altukhov DA, Lipkin AV, Kozlov SA, Tikhonov DB, Grishin EV
- Журнал: Scientific reports
- Том: 5
- Номер: 17232
- Год издания: 2015
- Издательство: Nature Publishing Group
- Местоположение издательства: United Kingdom
- Первая страница: 1
- Последняя страница: 15
- DOI: 10.1038/srep17232
- Аннотация: Novel disulfide-containing polypeptide toxin was discovered in the venom of the Tibellus oblongus spider. We report on isolation, spatial structure determination and electrophysiological characterization of this 41-residue toxin, called ω-Tbo-IT1. It has an insect-toxic effect with LD50 19 μg/g in experiments on house fly Musca domestica larvae and with LD50 20 μg/g on juvenile Gromphadorhina portentosa cockroaches. Electrophysiological experiments revealed a reversible inhibition of evoked excitatory postsynaptic currents in blow fly Calliphora vicina neuromuscular junctions, while parameters of spontaneous ones were not affected. The inhibition was concentration dependent, with IC50 value 40 ± 10 nM and Hill coefficient 3.4 ± 0.3. The toxin did not affect frog neuromuscular junctions or glutamatergic and GABAergic transmission in rat brains. Ca2+ currents in Calliphora vicina muscle were not inhibited, whereas in Periplaneta americana cockroach neurons at least one type of voltage gated Ca2+ current was inhibited by ω-Tbo-IT1. Thus, the toxin apparently acts as an inhibitor of presynaptic insect Ca2+ channels. Spatial structure analysis of the recombinant ω-Tbo-IT1 by NMR spectroscopy in aqueous solution revealed that the toxin comprises the conventional ICK fold containing an extended β-hairpin loop and short β-hairpin loop which are capable of making “scissors-like mutual motions”.
- Добавил в систему: Липкин Алексей Валерьевич