Local inhibitory action of BMPs and their relationships with activators in feather formation: implications for periodic patterning

Dev Biol. 1998 Apr 1;196(1):11-23. doi: 10.1006/dbio.1998.8850.

Abstract

The formation of periodic patterns is fundamental in biology. Theoretical models describing these phenomena have been proposed for feather patterning; however, no molecular candidates have been identified. Here we show that the feather tract is initiated by a continuous stripe of Shh, Fgf-4, and Ptc expression in the epithelium, which then segregates into discrete feather primordia that are more strongly Shh and Fgf-4 positive. The primordia also become Bmp-2 and Bmp-4 positive. Bead-mediated delivery of BMPs inhibits local feather formation in contrast with the activators, SHH and FGF-4, which induce feather formation. Both FGF-4 and SHH induce local expression of Bmp-4, while BMP-4 suppresses local expression of both. FGF-4 also induces Shh. Based on these findings, we propose a model that involves (1) homogeneously distributed global activators that define the field, (2) a position-dependent activator of competence that propagates across the field, and (3) local activators and inhibitors triggered in sites of individual primordia that act in a reaction-diffusion mechanism. A computer simulation model for feather pattern formation is also presented.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Body Patterning*
  • Bone Morphogenetic Protein 2
  • Bone Morphogenetic Protein 4
  • Bone Morphogenetic Proteins / pharmacology*
  • Chick Embryo
  • Dose-Response Relationship, Drug
  • Factor IX / metabolism
  • Feathers / embryology*
  • Fibroblast Growth Factor 4
  • Fibroblast Growth Factors / metabolism
  • Gene Expression Regulation, Developmental
  • Hedgehog Proteins
  • Models, Biological
  • Periodicity
  • Proteins / metabolism
  • Proto-Oncogene Proteins / metabolism
  • Skin / embryology*
  • Tissue Distribution
  • Trans-Activators*
  • Transforming Growth Factor beta*

Substances

  • Bone Morphogenetic Protein 2
  • Bone Morphogenetic Protein 4
  • Bone Morphogenetic Proteins
  • Fibroblast Growth Factor 4
  • Hedgehog Proteins
  • Proteins
  • Proto-Oncogene Proteins
  • Trans-Activators
  • Transforming Growth Factor beta
  • Fibroblast Growth Factors
  • Factor IX