Retrograde BMP signaling activates neuronal gene expression through widespread deployment of a conserved BMP-responsive cis-regulatory activation element

Nucleic Acids Res. 2019 Jan 25;47(2):679-699. doi: 10.1093/nar/gky1135.

Abstract

Retrograde Bone Morphogenetic Protein (BMP) signaling in neurons is essential for the differentiation and synaptic function of many neuronal subtypes. BMP signaling regulates these processes via Smad transcription factor activity, yet the scope and nature of Smad-dependent gene regulation in neurons are mostly unknown. Here, we applied a computational approach to predict Smad-binding cis-regulatory BMP-Activating Elements (BMP-AEs) in Drosophila, followed by transgenic in vivo reporter analysis to test their neuronal subtype enhancer activity in the larval central nervous system (CNS). We identified 34 BMP-AE-containing genomic fragments that are responsive to BMP signaling in neurons, and showed that the embedded BMP-AEs are required for this activity. RNA-seq analysis identified BMP-responsive genes in the CNS and revealed that BMP-AEs selectively enrich near BMP-activated genes. These data suggest that functional BMP-AEs control nearby BMP-activated genes, which we validated experimentally. Finally, we demonstrated that the BMP-AE motif mediates a conserved Smad-responsive function in the Drosophila and vertebrate CNS. Our results provide evidence that BMP signaling controls neuronal function by directly coordinating the expression of a battery of genes through widespread deployment of a conserved Smad-responsive cis-regulatory motif.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Ly / genetics
  • Antigens, Ly / metabolism
  • Bone Morphogenetic Proteins / physiology*
  • Chick Embryo
  • DNA-Binding Proteins / metabolism
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Drosophila Proteins / physiology*
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / metabolism
  • Evolution, Molecular
  • GPI-Linked Proteins / genetics
  • GPI-Linked Proteins / metabolism
  • Neurons / metabolism*
  • Response Elements*
  • Signal Transduction*
  • Smad Proteins / metabolism
  • Smad4 Protein / metabolism
  • Transcription Factors / metabolism
  • Transcriptional Activation*

Substances

  • Antigens, Ly
  • Bone Morphogenetic Proteins
  • DNA-Binding Proteins
  • Drosophila Proteins
  • GPI-Linked Proteins
  • MAD protein, Drosophila
  • Med protein, Drosophila
  • Smad Proteins
  • Smad4 Protein
  • Transcription Factors
  • twit protein, Drosophila

Grants and funding