Optogenetic control of the Bicoid morphogen reveals fast and slow modes of gap gene regulation.

Publication Year
2022

Type

Journal Article
Abstract

Developmental patterning networks are regulated by multiple inputs and feedback connections that rapidly reshape gene expression, limiting the information that can be gained solely from slow genetic perturbations. Here we show that fast optogenetic stimuli, real-time transcriptional reporters, and a simplified genetic background can be combined to reveal the kinetics of gene expression downstream of a developmental transcription factor in vivo. We engineer light-controlled versions of the Bicoid transcription factor and study their effects on downstream gap genes in embryos. Our results recapitulate known relationships, including rapid Bicoid-dependent transcription of giant and hunchback and delayed repression of Krüppel. In addition, we find that the posterior pattern of knirps exhibits a quick but inverted response to Bicoid perturbation, suggesting a noncanonical role for Bicoid in directly suppressing knirps transcription. Acute modulation of transcription factor concentration while recording output gene activity represents a powerful approach for studying developmental gene networks in vivo.

Journal
Cell Rep
Volume
38
Issue
12
Pages
110543
Date Published
2022 Mar 22
ISSN Number
2211-1247
Alternate Journal
Cell Rep
PMCID
PMC9019726
PMID
35320726