ZFIN ID: ZDB-PUB-130711-1
edn1 and hand2 Interact in Early Regulation of Pharyngeal Arch Outgrowth during Zebrafish Development
Sasaki, M.M., Nichols, J.T., and Kimmel, C.B.
Date: 2013
Source: PLoS One   8(6): e67522 (Journal)
Registered Authors: Kimmel, Charles B., Nichols, James Tucker, Sasaki, Mark
Keywords: none
MeSH Terms:
  • Animals
  • Basic Helix-Loop-Helix Transcription Factors/genetics
  • Basic Helix-Loop-Helix Transcription Factors/metabolism*
  • Body Patterning/genetics
  • Branchial Region/cytology
  • Branchial Region/embryology*
  • Branchial Region/metabolism*
  • Cartilage/embryology
  • Cartilage/metabolism
  • Cell Proliferation
  • Endothelin-1/genetics
  • Endothelin-1/metabolism*
  • Epistasis, Genetic
  • Gene Expression Regulation, Developmental
  • Gene Regulatory Networks
  • Green Fluorescent Proteins/metabolism
  • Larva/metabolism
  • Phenotype
  • Principal Component Analysis
  • Zebrafish/embryology*
  • Zebrafish/metabolism*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
PubMed: 23826316 Full text @ PLoS One

Endothelin-1 (Edn1) signaling provides a critical input to development of the embryonic pharygneal arches and their skeletal derivatives, particularly the articulating joints and the ventral skeleton including the lower jaw. Previous work in zebrafish has mostly focused on the role of Edn1 in dorsal-ventral (DV) patterning, but Edn1 signaling must also regulate tissue size, for with severe loss of the pathway the ventral skeleton is not only mispatterned, but is also prominently hypoplastic – reduced in size. Here we use mutational analyses to show that in the early pharyngeal arches, ventral-specific edn1-mediated proliferation of neural crest derived cells is required for DV expansion and outgrowth, and that this positive regulation is counterbalanced by a negative one exerted through a pivotal, ventrally expressed Edn1-target gene, hand2. We also describe a new morphogenetic cell movement in the ventral first arch, sweeping cells anterior in the arch to the region where the lower jaw forms. This movement is negatively regulated by hand2 in an apparently edn1-independent fashion. These findings point to complexity of regulation by edn1 and hand2 at the earliest stages of pharyngeal arch development, in which control of growth and morphogenesis can be genetically separated.