AP-1 subunits converge promiscuously at enhancers to potentiate transcription
Abstract
The AP-1 transcription factor dimer contributes to many biological processes and environmental responses. The many ways that AP-1 subunits can dimerize has posed a challenge to understanding its regulatory function. To determine patterns of AP-1 dimerization genome-wide, we definitively establish the genome-wide binding patterns and the enhancer function of five AP-1 subunits. We find limited evidence for strong dimerization preferences between specific subunits. In particular, our analysis suggests that canonical AP-1 motifs have the potential to recruit all AP-1 subunits to genomic sites that also have hallmarks of strong enhancer activity. We term those sites AP-1 hotspots. AP-1 hotspots function as a ‘hub' for AP-1 subunit binding that elicits changes in cell type–specific AP-1-mediated gene expression. AP-1 hotspots are more predictive of genomic responses to glucocorticoid signaling than super enhancers, and are particularly enriched in disease-associated genetic variants. Together, these results support a model that promiscuous convergence of many subunits to common genomic locations potentiates AP-1-mediated transcription in a cell type–specific fashion.
- Received June 25, 2020.
- Accepted February 17, 2021.
- Published by Cold Spring Harbor Laboratory Press
This manuscript is Open Access.
This article, published in Genome Research, is available under a Creative Commons License (Attribution-NonCommercial 4.0 International license), as described at http://creativecommons.org/licenses/by-nc/4.0/.
