БИОХИМИЯ, 2021, том 86, вып. 8, с. 1160–1175

УДК 577.218

Механизмы работы рибопереключателей: новые трюки для старой собаки

Обзор

© 2021 A. Ariza-Mateos, A. Nuthanakanti, A. Serganov *alexander.serganov@nyulangone.org

Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, New York 10016, USA

Поступила в редакцию 01.05.2021
После доработки 01.05.2021
Принята к публикации 19.05.2021

DOI: 10.31857/S032097252108008X

КЛЮЧЕВЫЕ СЛОВА: рибопереключатель, транскрипция, трансляция, мРНК, метаболит.

Аннотация

Обнаруженные почти двадцать лет назад рибопереключатели оказались одной из самых распространенных регуляторных систем у бактерий, они встречаются как у эукариот, так и у архей. В отличие от многих других регуляторных элементов, рибопереключатели полностью состоят из РНК и способны модулировать экспрессию генов в клетке путём прямого связывания небольших молекул. Первоначально считалось, что бактериальные рибопереключатели через регуляторные цепи обратной связи контролируют синтез только тех ферментов и транспортёров, которые связаны с небольшими органическими молекулами. Однако более поздние открытия выявили рибопереключатели, управляющие экспрессией широкого спектра генов и отвечающие на различные классы молекул, включая ионы, сигнальные молекулы и другие. Подавляющее большинство рибопереключателей находятся в 5′-нетранслируемой области мРНК. Рибопереключатели модулируют транскрипцию или трансляцию нижестоящих генов посредством конформационных перестроек в лиганд-чувствительных доменах и примыкающих к ним платформах, контролирующих экспрессию. С годами набор изученных регуляторных механизмов, используемых рибопереключателями, значительно расширился; самые последние исследования подчеркнули важность альтернативных механизмов, таких как деградация РНК, для генетических цепей, управляемых рибопереключателями. В этом обзоре обсуждается множество бактериальных механизмов рибопереключения и показано, каким образом рибопереключатели используют характерные особенности и способы для получения различных регуляторных ответов.

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* Адресат для корреспонденции.

Финансирование

Работа поддержана грантом Фонда Рамона Аресеса (Ramon Areces Foundation) (A.A.-M.) и грантом Национального института здравоохранения 2R01GM112940 (A.S.).

Конфликт интересов

Авторы заявляют об отсутствии конфликта интересов в финансовой или иной сфере.

Соблюдение этических норм

Эта статья не содержит исследований с участием людей или животных, выполненных кем-либо из авторов.

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