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Title: Применение спектральных методов для исследования родопсина ---рецептора, сопряженного с G-белком. III. Эффект осмотического давления
Обобщены результаты исследований рецепторов, сопряженных с G-белком. Несмотря на установленное присутствие небольшого количества структурной воды в этих рецепторах влияние объемного растворителя (воды) на их функционирование остается малоизученным. Исследования с применением осмотического давления позволили получить уникальные данные о роли воды в активации родопсина. Обнаружено, что осмолиты в зависимости от их молекулярного веса сдвигают равновесие в сторону либо активного (низкомолекулярные осмолиты), либо неактивного состояния (высокомолекулярные). Экспериментально показано, что примерно 80 молекул воды попадают в родопсин при его активации. Это является необходимым условием активации и в случае блокирования входа воды в белок, например, высокомолекулярными осмолитами или дегидратацией рецептор не переходит в активное состояние. Полученные результаты позволяют предложить новую модель активации рецепторов, сопряженных с G-белком, в которой протеин набухает и частично разворачивается при переходе в активное состояние. Таким образом, вода действует как мощный модулятор функционирования родопсино-подобных белков. Ключевые слова: мембраны, родопсин, рецепторы, сопряженные с G-белком, сигнальная трансдукция, оптическая спектроскопия.  more » « less
Award ID(s):
1904125 1817862
NSF-PAR ID:
10435920
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Оптика и спектроскопия
Volume:
131
Issue:
1
ISSN:
0030-4034
Page Range / eLocation ID:
123
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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