Biopolym. Cell. 2002; 18(6):500-517.
Структура та функції біополімерів
Допоміжні елементи полі (А)-сигналів пре-мРНК ссавців
1Зарудна М. І., 1Потягайло А. Л., 1Коломієць І. М., 1Говорун Д. М.
  1. Інститут молекулярної біології і генетики НАН України
    Вул. Академіка Заболотного, 150, Київ, Україна, 03680

Abstract

Поліаденілування – один з клітинних процесів, на рівні яких відбувається регуляція експресії генів. Допоміжні елементи полі(А)-сигналів про-мРНК ссавців стимулюють або при­гнічують реакцію поліаденілування, що спрямовується кор-елементами сигналів. У цій роботі ми обговорюємо структуpy і функції відомих в літературі допоміжних елементів та проводимо їхній пошук у створеній нами базі даних полі(А)-сигналів про-мРНК людини, яка містить 244 послідовності про-мРНК в області місця розщеплення. Аналіз літератури і створеної бази даних свідчить про широку поширеність у клітинних про-мРНК допоміжних елементів, зокрема послі­довностей, що зв'язують VI мяРНП-специфічний VIA білок. Окрім того, в створеній базі даних здійснено пошук послідо­вностей про-мРНК, які можуть утворювати чотирьохланцюгові структури (G-квадруплекси або і-мотиви). Ми припусти­ли, що такі структури здатні виконувати деякі функції допоміжних елементів. У роботі наведено моделі квадруплексів для фрагментів деяких про-мРНК людини, які грунту­ються на аналізі літератури, присвяченій чотирьохспіральним структурам, а також моделі G-квадруплексів для допоміж­ного G-багатого елемента полі(А)-сигналу про-мРНК SV40 L.

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