NKX2-5 mutations causative for congenital heart disease retain functionality and are directed to hundreds of targets
- Victor Chang Cardiac Research Institute, Australia
- Université Libre de Bruxelles, Belgium
- Monash University, Australia
- University of Oxford, United Kingdom
Abstract
To model cardiac gene regulatory networks in health and disease we used DamID to establish robust target gene sets for the cardiac homeodomain factor NKX2-5 and two congenital heart disease-associated mutants carrying a crippled homeodomain, which normally functions as DNA- and protein-binding interface. Despite compromised direct DNA-binding, NKX2-5 mutants retained partial functionality and bound hundreds of targets, including NKX2-5 wild type targets and unique sets of 'off-targets'. NKX2-5∆HD, which lacks the entire homeodomain, could still dimerise with wild type NKX2-5 and its cofactors, including newly-discovered cofactors of the ETS family, through the conserved tyrosine-rich domain (YRD). NKX2-5∆HD off-targets showed overrepresentation of many binding motifs, including ETS motifs, the majority co-occupied by ETS proteins as determined by DamID. Off-targets of an NKX2-5 YRD mutant were not enriched in ETS targets. Our study reveals off-target binding and transcriptional activity for NKX2-5 mutations driven in part by cofactor interactions, suggesting a novel type of gain-of-function in congenital heart disease.
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Ethics
Animal experimentation: Animal experimentation was performed with approval of the Garvan Institute/St Vincent's Hospital Animal Ethics Committee (Project numbers 10/19 and 10/01).
Copyright
© 2015, Bouveret 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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NKX2-5 mutations causative for congenital heart disease retain functionality and are directed to hundreds of targets
eLife 4:e06942.
https://doi.org/10.7554/eLife.06942
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