Роль системы РНК-интерференции в регуляции длины теломер Drosophila

Выводы:

1. Транскрипты теломерных ретротранспозонов НеТ-А и TART накапливаются в яичниках мух, мутантных по генам РНКи spn-E и aub. В отличие от транскриптов НеТ-А, локализующихся в ооците, транскрипты TART накапливаются на поздних стадиях оогенеза в питающих клетках.

2. Продемонстрировано участие механизма РНКи в контроле длины теломер дрозофилы. Частота транспозиций теломерных ретротранспозонов к концу терминально-делетированной хромосомы увеличивается на фоне мутаций РНКи генов spn-E и aub. Мутантный аллель в гетерозиготном состоянии вызывает преимущественные транспозиции ретроэлемента TART, а в гомозиготном — НеТ-А элемента.

3. Недавно обнаруженный ретротранспозон TAHRE способен перемещаться на конец хромосомы, и, следовательно, этот элемент является полноправным участником поддержания теломер у дрозофилы.

4. Промотор ретротранспозона TAHRE, так же как у НеТ-А, находится в конце 3' нетранслируемой области данного элемента.

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