Doklady Biological SciencesDoklady Biological SciencesДоклады Российской академии наук. Науки о жизни2686-73893034-5057The Russian Academy of Sciences68405110.31857/S2686738925020125ArticlesСтатьиResearch ArticleThe bxd pre from bithorax complex of Drosophila melanogaster has weak insulator activitybxd PRE комплекса bithorax Drosophila melanogaster обладает слабой инсуляторной активностьюIbragimovА. N.ИбрагимовА. Н.
Russian Federation
airat.ibra@gmail.comKyrchanovaO. V.КырчановаО. В.
Russian Federation
airat.ibra@gmail.comVorontsovaY. Е.ВоронцоваЮ. Е.
Russian Federation
airat.ibra@gmail.comKozlovE. N.КозловЕ. Н.
Russian Federation
airat.ibra@gmail.comDubrovskayaV. O.ДубровскаяВ. О.
Russian Federation
airat.ibra@gmail.comGeorgievP. G.ГеоргиевП. Г.
Russian Federation

Academician of the RAS

академик РАН

airat.ibra@gmail.comInstitute of gene biology, Russian academy of scienceИнститут биологии гена, Российская академия наук1504202552112352391206202512062025Copyright ©; 2025, Russian Academy of SciencesCopyright ©; 2025, Российская академия наук2025Russian Academy of SciencesРоссийская академия наукhttps://journals.eco-vector.com/2686-7389/article/view/684051

The autonomous functioning of regulatory domains in the Bithorax complex (BX-C) of Drosophila melanogaster is maintained by boundaries (insulators) that prevent inappropriate enhancer–promoter interactions. Polycomb response elements (PREs) maintain epigenetic memory within regulatory domains and are often located near insulators, enhancing their blocking activity. The bxd PRE is a well-characterized silencer that regulates the bxd/pbx domain of the Ubx gene in the first abdominal segment. We used a boundary replacement strategy to assess the insulator activity of the bxd PRE. Substituting the bxd PRE for the Fab-7 boundary, which separates the Abd-B regulatory domains in the BX-C, revealed that the bxd PRE has weak insulator activity.

Автономное функционирование регуляторных доменов в комплексе Bithorax (BX-C) Drosophila melanogaster обеспечивается границами (инсуляторами), которые предотвращают взаимодействия между энхансерами и промоторами. Сайленсеры (Polycomb response elements) поддерживают эпигенетическую память в пределах регуляторных доменов и часто расположены рядом с инсуляторами, усиливая их инсуляторную активность. bxd PRE — это хорошо известный сайленсер, который регулирует активность домена bxd/pbx гена Ubx (один из генов BX-C) в первом абдоминальном сегменте. Для исследования инсуляторной активности bxd PRE мы применили стратегию замены границы. В результате было показано, что при интеграции на место границы Fab-7, разделяющей регуляторные домены гена Abd-B в локусе BX-C, bxd PRE обладает слабой инсуляторной активностью.

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