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Updated: Aug 7, 2026
10:46
Dissection of Enhancer Function Using Multiplex CRISPR-based Enhancer Interference in Cell Lines
Published on: June 2, 2018
Dissecting a locus control region: facilitation of enhancer function by extended enhancer-flanking sequences
B J Aronow1, C A Ebert, M T Valerius
1Department of Pediatrics, Children's Hospital Medical Center, University of Cincinnati College of Medicine, Ohio 45229.
Molecular and Cellular Biology
|February 1, 1995
Summary
Novel gene regulatory elements called facilitators are essential for T-cell specific enhancer function in the adenosine deaminase (ADA) gene. These elements are crucial for reporter expression and proper chromatin structure formation.
Area of Science:
- Molecular Biology
- Genetics
- Immunology
Background:
- The adenosine deaminase (ADA) gene plays a critical role in immune system function.
- Understanding gene regulation in T-cells is crucial for developing targeted therapies.
Purpose of the Study:
- To identify and characterize novel gene regulatory elements controlling T-cell specific enhancer activity.
- To elucidate the mechanism by which these elements influence enhancer function and chromatin structure.
Main Methods:
- Utilized transgenic mice models to study gene regulation.
- Employed reporter gene assays to assess enhancer activity.
- Investigated chromatin structure using DNase I hypersensitivity assays.
- Analyzed protein-DNA interactions using restriction endonuclease accessibility assays.
Main Results:
- Identified novel regulatory elements, termed "facilitators," flanking the ADA gene enhancer.
- Facilitators are essential for enhancer activity in thymocytes, but not in transfected T cells.
- Facilitator function is required for DNase I-hypersensitive site formation and proper chromatin structure.
- Facilitators act after initial cell-type-specific accessibility to the enhancer is established.
Conclusions:
- Facilitators are distinct regulatory elements that are positionally constrained to the enhancer.
- They are critical for establishing the active chromatin state necessary for enhancer function.
- Facilitators play a key role in the multi-step process of T-cell specific gene activation.
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