РОЛЬ СПЛАЙС-ВАРИАНТОВ КАТАЛИТИЧЕСКОЙ СУБЪЕДИНИЦЫ ТЕЛОМЕРАЗЫ ЧЕЛОВЕКА HTERT В ФИЗИОЛОГИЧЕСКИХ И ПАТОЛОГИЧЕСКИХ КЛЕТОЧНЫХ ПРОЦЕССАХ

DOI: https://doi.org/None

Д.Д. Жданов (1), кандидат биологических наук, А.В. Лохонина (2), Н.Н. Соколов (1), доктор биологических наук, профессор 1-Научно-исследовательский институт биомедицинской химии им. В.Н. Ореховича, Российская Федерация, 119121, Москва, ул. Погодинская, д. 10, стр. 8; 2-Российский национальный исследовательский медицинский университет им. Н.И. Пирогова Минздрава России, Российская Федерация, 117997, Москва, ул. Островитянова, д. 1 E-mail: [email protected]

Каталитическая субъединица теломеразы hTERT регулируется на транскрипционном и посттранскрипционном уровнях. Одним из механизмов регуляции является альтернативный сплайсинг ее мРНК. Каталитической активностью и способностью удлинять теломеры обладает только полноразмерная форма. Сплайс-варианты hTERT обнаружены во множестве тканей и в тканевых культурах; они составляют большую часть тотальной hTERT-клетки и участвуют в регуляции теломеразной активности при физиологических и патологических процессах. Изменение соотношения количества различных сплайс-вариантов имеет тканевую специфичность, наблюдается при клеточной дифференциации, эмбриональном развитии, злокачественной трансформации клеток, а также при различных внешних воздействиях. Появляется все больше доказательств наличия нетрадиционных, экстрателомерных функций у молекулы hTERT, а именно – ее участия в процессе репарации ДНК, антиапоптотической активности, активации клеточных систем пролиферации, а также роли при оксидативном повреждении митохондриальной ДНК. Видимо, эти функции hTERT важны при злокачественной трансформации клеток и могут объяснить независимый от удлинения теломер эффект опухолевого развития. В обзоре описаны варианты альтернативного cплайсинга hTERT, их связь с теломеразной активностью и длиной теломер, роль в различных клеточных процессах, а также экстрателомерные функции hTERT.
Ключевые слова: 
теломеры, теломераза, hTERT, альтернативный сплайсинг, сплайс- вариант, апоптоз
Для цитирования: 
Жданов Д.Д., Лохонина А.В., Соколов Н.Н. РОЛЬ СПЛАЙС-ВАРИАНТОВ КАТАЛИТИЧЕСКОЙ СУБЪЕДИНИЦЫ ТЕЛОМЕРАЗЫ ЧЕЛОВЕКА HTERT В ФИЗИОЛОГИЧЕСКИХ И ПАТОЛОГИЧЕСКИХ КЛЕТОЧНЫХ ПРОЦЕССАХ. Молекулярная медицина, 2017; (1): -
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