Quantitative dissection of transcription in development yields evidence for transcription-factor-driven chromatin accessibility

Abstract

Thermodynamic models of gene regulation can predict transcriptional regulation in bacteria, but in eukaryotes, chromatin accessibility and energy expenditure may call for a different framework. Here, we systematically tested the predictive power of models of DNA accessibility based on the Monod-Wyman-Changeux (MWC) model of allostery, which posits that chromatin fluctuates between accessible and inaccessible states. We dissected the regulatory dynamics ofhunchbackby the activator Bicoid and the pioneer-like transcription factor Zelda in livingDrosophilaembryos and showed that no thermodynamic or non-equilibrium MWC model can recapitulatehunchbacktranscription. Therefore, we explored a model where DNA accessibility is not the result of thermal fluctuations but is catalyzed by Bicoid and Zelda, possibly through histone acetylation, and found that this model can predicthunchbackdynamics. Thus, our theory-experiment dialogue uncovered potential molecular mechanisms of transcriptional regulatory dynamics, a key step toward reaching a predictive understanding of developmental decision-making.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 19, 2020
Source ID
10.7554/elife.56429

Entities

People

  • Elizabeth Eck
  • Hernan G. Garcia
  • Jonathan Liu
  • Maryam Kazemzadeh-atoufi
  • Shelby A. Blythe
  • Sydney Ghoreishi

Organizations

  • Burroughs Wellcome Fund
  • Hellman Foundation
  • Human Frontier Science Program
  • National Institutes of Health
  • National Science Foundation
  • Northwestern University
  • Shurl and Kay Curci Foundation
  • United States Department of Defense
  • University of California, Berkeley

Tags

Fields of Study

  • Biology

Readers

  • Molecular Biology and Genetics
  • Molecular Genetics
  • Theoretical Analysis.