ZFIN ID: ZDB-PUB-051121-10
Characterization of two new zebrafish members of the hedgehog family: Atypical expression of a zebrafish indian hedgehog gene in skeletal elements of both endochondral and dermal origins
Avaron, F., Hoffman, L., Guay, D., and Akimenko, M.A.
Date: 2006
Source: Developmental dynamics : an official publication of the American Association of Anatomists   235(2): 478-489 (Journal)
Registered Authors: Akimenko, Marie-Andree, Avaron, Fabien
Keywords: Indian hedgehog, collagen type X, zebrafish, endoskeleton, dermal bone, fin regeneration, cartilage, extracellular matrix
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Collagen Type X/metabolism
  • Gene Expression Regulation, Developmental/genetics*
  • Hedgehog Proteins/chemistry
  • Hedgehog Proteins/classification*
  • Hedgehog Proteins/genetics
  • Hedgehog Proteins/metabolism*
  • Humans
  • Larva/genetics
  • Larva/metabolism
  • Molecular Sequence Data
  • Musculoskeletal System/chemistry
  • Musculoskeletal System/embryology*
  • Musculoskeletal System/metabolism*
  • Phylogeny
  • Sequence Alignment
  • Trans-Activators/chemistry
  • Trans-Activators/classification*
  • Trans-Activators/genetics
  • Trans-Activators/metabolism*
  • Zebrafish/classification
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish/metabolism*
  • Zebrafish Proteins/chemistry
  • Zebrafish Proteins/classification*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
PubMed: 16292774 Full text @ Dev. Dyn.
We have characterized two new members of the Hedgehog (Hh) family in zebrafish, ihha and dhh, encoding for orthologues of the tetrapod Indian Hedgehog (Ihh) and Desert Hedgehog (Dhh) genes, respectively. Comparison of ihha and Type X collagen (col10a1) expression during skeletal development show that ihha transcripts are located in hypertrophic chondrocytes of cartilaginous elements of the craniofacial and fin endoskeleton. Surprisingly, col10a1 expression was also detected in cells forming intramembranous bones of the head and in flat cells surrounding cartilaginous structures. The expression of col10a1 in both endochondral and intramembranous bones reflects an atypical composition of the extracellular matrix of the zebrafish craniofacial skeleton. In addition, during fin ray regeneration, both ihha and col10a1 are detected in scleroblasts, osteoblast-like cells secreting the matrix of the dermal bone fin ray. The presence of cartilage markers suggests that the dermal fin ray possesses an intermediate phenotype between cartilage and bone.