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.
Article and author information
Author details
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.
Metrics
-
- 3,756
- views
-
- 741
- downloads
-
- 58
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
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
Further reading
-
- Developmental Biology
Juvenile hormone (JH) is important to maintain insect larval status; however, its cell membrane receptor has not been identified. Using the lepidopteran insect Helicoverpa armigera (cotton bollworm), a serious agricultural pest, as a model, we determined that receptor tyrosine kinases (RTKs) cadherin 96ca (CAD96CA) and fibroblast growth factor receptor homologue (FGFR1) function as JH cell membrane receptors by their roles in JH-regulated gene expression, larval status maintaining, rapid intracellular calcium increase, phosphorylation of JH intracellular receptor MET1 and cofactor Taiman, and high affinity to JH III. Gene knockout of Cad96ca and Fgfr1 by CRISPR/Cas9 in embryo and knockdown in various insect cells, and overexpression of CAD96CA and FGFR1 in mammalian HEK-293T cells all supported CAD96CA and FGFR1 transmitting JH signal as JH cell membrane receptors.
-
- Developmental Biology
- Neuroscience
In the developing vertebrate central nervous system, neurons and glia typically arise sequentially from common progenitors. Here, we report that the transcription factor Forkhead Box G1 (Foxg1) regulates gliogenesis in the mouse neocortex via distinct cell-autonomous roles in progenitors and postmitotic neurons that regulate different aspects of the gliogenic FGF signalling pathway. We demonstrate that loss of Foxg1 in cortical progenitors at neurogenic stages causes premature astrogliogenesis. We identify a novel FOXG1 target, the pro-gliogenic FGF pathway component Fgfr3, which is suppressed by FOXG1 cell-autonomously to maintain neurogenesis. Furthermore, FOXG1 can also suppress premature astrogliogenesis triggered by the augmentation of FGF signalling. We identify a second novel function of FOXG1 in regulating the expression of gliogenic cues in newborn neocortical upper-layer neurons. Loss of FOXG1 in postmitotic neurons non-autonomously enhances gliogenesis in the progenitors via FGF signalling. These results fit well with the model that newborn neurons secrete cues that trigger progenitors to produce the next wave of cell types, astrocytes. If FGF signalling is attenuated in Foxg1 null progenitors, they progress to oligodendrocyte production. Therefore, loss of FOXG1 transitions the progenitor to a gliogenic state, producing either astrocytes or oligodendrocytes depending on FGF signalling levels. Our results uncover how FOXG1 integrates extrinsic signalling via the FGF pathway to regulate the sequential generation of neurons, astrocytes, and oligodendrocytes in the cerebral cortex.
