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A cell-based bioluminescence assay reveals dose-dependent and contextual repression of AP-1-driven gene expression by BACH2.

ABSTRACT: Whereas effector CD4+ and CD8+ T cells promote immune activation and can drive clearance of infections and cancer, CD4+ regulatory T (Treg) cells suppress their function, contributing to both immune homeostasis and cancer immunosuppression. The transcription factor BACH2 functions as a pervasive regulator of T cell differentiation, promoting development of CD4+ Treg cells and suppressing the effector functions of multiple effector T cell (Teff) lineages. Here, we report the development of a stable cell-based bioluminescence assay of the transcription factor activity of BACH2. Tetracycline-inducible BACH2 expression resulted in suppression of phorbol 12-myristate 13-acetate (PMA)/ionomycin-driven activation of a luciferase reporter containing BACH2/AP-1 target sequences from the mouse Ifng?+?18k enhancer. BACH2 expression repressed the luciferase signal in a dose-dependent manner but this activity was abolished at high levels of AP-1 signalling, suggesting contextual regulation of AP-1 driven gene expression by BACH2. Finally, using the reporter assay developed, we find that the histone deacetylase 3 (HDAC3)-selective inhibitor, RGFP966, inhibits BACH2-mediated repression of signal-driven luciferase expression. In addition to enabling mechanistic studies, this cell-based reporter may enable identification of small molecule agonists or antagonists of BACH2 function for drug development.

SUBMITTER: Vardaka P

PROVIDER: S-EPMC7641119 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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A cell-based bioluminescence assay reveals dose-dependent and contextual repression of AP-1-driven gene expression by BACH2.

Vardaka Panagiota P Lozano Teresa T Bot Christopher C Ellery Jonathan J Whiteside Sarah K SK Imianowski Charlotte J CJ Farrow Stuart S Walker Simon S Okkenhaug Hanneke H Yang Jie J Okkenhaug Klaus K Kuo Paula P Roychoudhuri Rahul R

Scientific reports 20201103 1

Whereas effector CD4+ and CD8+ T cells promote immune activation and can drive clearance of infections and cancer, CD4+ regulatory T (Treg) cells suppress their function, contributing to both immune homeostasis and cancer immunosuppression. The transcription factor BACH2 functions as a pervasive regulator of T cell differentiation, promoting development of CD4+ Treg cells and suppressing the effector functions of multiple effector ...[more]

PMID: 33144667

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Dataset Information

A cell-based bioluminescence assay reveals dose-dependent and contextual repression of AP-1-driven gene expression by BACH2.

Publications

A cell-based bioluminescence assay reveals dose-dependent and contextual repression of AP-1-driven gene expression by BACH2.

Similar Datasets

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