lncRNA read-through regulates the BX-C insulator Fub-1
Abstract
hough long non-coding RNAs (lncRNAs) represent a substantial fraction of the Pol II transcripts in multicellular animals, only a few have known functions. Here we report that the blocking activity of the Bithorax complex (BX-C) Fub-1 boundary is segmentally regulated by its own lncRNA. The Fub-1 boundary is located between the Ultrabithorax (Ubx) gene and the bxd/pbx regulatory domain, which is responsible for regulating Ubx expression in parasegment PS6/segment A1. Fub-1 consists of two hypersensitive sites, HS1 and HS2. HS1 is an insulator while HS2 functions primarily as a lncRNA promoter. To activate Ubx expression in PS6/A1 enhancers in the bxd/pbx domain must be able to bypass Fub-1 blocking activity. We show that expression of the Fub-1 lncRNAs in PS6/A1 from the HS2 promoter inactivates Fub-1 insulating activity. Inactivation is due to readthrough as the HS2 promoter must be directed towards HS1 to disrupt blocking.
Data availability
Sequencing data have been deposited in GEO under accession code GSE217005. The data can be accessed using the following secure token sxyxomkyjlgxvmj
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R35 GM126975)
- Paul Schedl
National Institute of General Medical Sciences (R01 GM118147)
- Michael Levine
Russian Science Foundation (20-14-00201)
- Yulii Shidlovskii
Russian Science Foundation (19-14-00103)
- Pavel Georgiev
Ministry of Science and Higher Education of the Russian Federation (075-15-2019-1661)
- Pavel Georgiev
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Howard Y Chang, Stanford University, United States
Version history
- Received: November 5, 2022
- Preprint posted: November 15, 2022 (view preprint)
- Accepted: August 9, 2023
- Accepted Manuscript published: August 10, 2023 (version 1)
- Version of Record published: September 12, 2023 (version 2)
Copyright
© 2023, Ibragimov et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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