PUBLICATION

Hedgehog signaling is necessary and sufficient to mediate craniofacial plasticity in teleosts

Authors
Navon, D., Male, I., Tetrault, E.R., Aaronson, B., Karlstrom, R.O., Albertson, R.C.
ID
ZDB-PUB-200729-4
Date
2020
Source
Proceedings of the National Academy of Sciences of the United States of America   117(32): 19321-19327 (Journal)
Registered Authors
Albertson, R. Craig, Karlstrom, Rolf
Keywords
craniofacial, ecodevo, flexible stem, hedgehog signaling, phenotypic plasticity
MeSH Terms
  • Adaptation, Physiological
  • Animals
  • Cichlids/genetics
  • Cichlids/growth & development
  • Cichlids/metabolism*
  • Fish Proteins/genetics
  • Fish Proteins/metabolism*
  • Hedgehog Proteins/genetics
  • Hedgehog Proteins/metabolism*
  • Signal Transduction
  • Skull/growth & development*
  • Skull/metabolism
PubMed
32719137 Full text @ Proc. Natl. Acad. Sci. USA
Abstract
Phenotypic plasticity, the ability of a single genotype to produce multiple phenotypes under different environmental conditions, is critical for the origins and maintenance of biodiversity; however, the genetic mechanisms underlying plasticity as well as how variation in those mechanisms can drive evolutionary change remain poorly understood. Here, we examine the cichlid feeding apparatus, an icon of both prodigious evolutionary divergence and adaptive phenotypic plasticity. We first provide a tissue-level mechanism for plasticity in craniofacial shape by measuring rates of bone deposition within functionally salient elements of the feeding apparatus in fishes forced to employ alternate foraging modes. We show that levels and patterns of phenotypic plasticity are distinct among closely related cichlid species, underscoring the evolutionary potential of this trait. Next, we demonstrate that hedgehog (Hh) signaling, which has been implicated in the evolutionary divergence of cichlid feeding architecture, is associated with environmentally induced rates of bone deposition. Finally, to demonstrate that Hh levels are the cause of the plastic response and not simply the consequence of producing more bone, we use transgenic zebrafish in which Hh levels could be experimentally manipulated under different foraging conditions. Notably, we find that the ability to modulate bone deposition rates in different environments is dampened when Hh levels are reduced, whereas the sensitivity of bone deposition to different mechanical demands increases with elevated Hh levels. These data advance a mechanistic understanding of phenotypic plasticity in the teleost feeding apparatus and in doing so contribute key insights into the origins of adaptive morphological radiations.
Genes / Markers
Figures
Expression
Phenotype
Mutation and Transgenics
Human Disease / Model Data
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping
Errata and Notes