СибНСХБ

Вид поиска

Область поиска

Найдено в других БД

Формат представления найденных документов:
библиографическое описание	краткий	полный

Поисковый запрос: (<.>S=ТИТИУСТОКСИН K['АЛЬФА']<.>)

Общее количество найденных документов : 1

РЖ ВИНИТИ 34 (BI34) 95.12-04Т4.178

Tityustoxin K'альфа' blocks voltage-gated noninactivating K{+} channels and unblocks inactivating K{+} channels blocked by 'альфа'-dendrotoxin in synaptosomes [Text] / Robert S. Rogowski [et al.] // Proc. Nat. Acad. Sci. USA. - 1994. - Vol. 91, N 4. - P1475-1479 . - ISSN 0027-8424
Перевод заглавия: Титиустоксин K['альфа'] блокирует потенциалзависимые калиевые каналы в синаптосомах и снимает блокаду последних 'альфа'-дендротоксином
Аннотация: Two nonhomologous polypeptide toxins, tityustoxin K'альфа' (TsTX-K'альфа') and tityustoxin K'бета' (TsTX-K'бета'), purified from the venom of the Brazilian scorpion Tityus serrulatus, selectively block voltage-gated noninactivating K{+} channels in synaptosomes (IC[50] values of 8 nM and 30 nM, respectively). In contrast, 'альфа'-dendrotoxin ('альфа'-DTX) and charybdotoxin (ChTX) block voltage-gated inactivating K{+} channels in synaptosomes (IC[50] values of 90 nM and 40 nM, respectively). We studied interactions among these toxins in {125}I-'альфа'-DTX binding and {86}Rb efflux experiments. Both TsTX-K'альфа' and ChTX completely displaced specifically bound {125}I-'альфа'-DTX from synaptic membranes, but TSTX-K'бета' had no effect on bound 'альфа'-DTX. TsTX-K'альфа' and TsTX-K'бета' blocked the same noninactivating component of 100 mM K{+}-stimulated {86}Rb efflux in synaptosomes. Both 'альфа'-DTX and ChTX blocked the same inactivating component of the K{+}-stimulated {86}Rb efflux in synaptosomes. Both the inactivating and the noninactivating components of the 100 mM K{+}-stimulated {86}Rb efflux were completely blocked when 200 nM TsTX-K'бета' and either 600 nM 'альфа'-DTX or 200 nM ChTX were present. The effects of TsTX-K'альфа' and ChTX on {86}Rb efflux were also additive. When TsTX-K'альфа' was added in the presence of 'альфа'-DTX, however, only the noninactivating component of the K{+}-stimulated efflux was blocked. The inactivating component could then be blocked by ChTX, which is structurally homologous to TsTX-K'альфа'. We conclude that TsTX-K'альфа' unblocks the voltage-gated inactivating K{+} channels in synaptosomes when they are blocked by 'альфа'-DTX, but not when they are blocked by ChTX. TsTX-K'альфа' binds to a site on the inactivating K{+} channel that does not occlude the pore; its binding apparently prevents 'альфа'-DTX (7054 Da), but not ChTX (4300 Da), from blocking the pore. The effects of TsTX-K'альфа' on {125}I-'альфа'-DTX binding and {86}Rb efflux are mimicked by noxiustoxin, which is homologous to TsTX-K'альфа' and ChTX. США, Dep. Physiol., Univ. Maryland Sch. Med., Baltimore, MD 21201. Библ. 31

ГРНТИ	34.47.21

ВИНИТИ 341.47.21.29.13.13.23
Рубрики: КАЛИЕВЫЕ КАНАЛЫ
ПОТЕНЦИАЛЗАВИСИМЫЕ
ЯД СКОРПИОНА
ТИТИУСТОКСИН K['АЛЬФА']
ВЛИЯНИЕ 'АЛЬФА'-ДЕНДРОТОКСИНА
СИНАПТОСОМЫ

Доп.точки доступа:
Rogowski, Robert S.; Krueger, Bruce K.; Collins, John H.; Blaustein, Mordecai P.

"Электронные каталоги и базы данных библиотек СО РАН"

© Международная Ассоциация пользователей и разработчиков электронных библиотек и новых информационных технологий
(Ассоциация ЭБНИТ)

rtvarBDview(" результаты поиска","20190607010228","4682442");

Вид поиска