Patterning of the mesoderm involves several threshold responses to BMP-4 and Xwnt-8

Mech Dev. 1999 Sep;87(1-2):33-44. doi: 10.1016/s0925-4773(99)00137-9.

Abstract

Two secreted signaling molecules, Xwnt-8 and BMP-4, play an essential role in the dorso-ventral patterning of the mesoderm in Xenopus. Here we investigate how the Wnt-8 and the BMP-4 pathways are connected and how they regulate target genes in the lateral and ventral marginal zone. BMP-4 regulates the transcription of Xwnt-8 in a threshold dependent manner. High levels of BMP-4 induce the expression of the Wnt antagonist sizzled in the ventral marginal zone, independent of Xwnt-8 signaling. Xwnt-8 induces the early muscle marker myf-5 in the lateral marginal zone in a BMP independent manner. The expression of the homeobox gene Xvent-1 can be modulated through both the BMP-4 and the Xwnt-8 pathways. The spatial distribution and the level of BMP-4 activity in the lateral and ventral marginal zone is reflected in the dynamic expression pattern of Xwnt-8. The data support the view that Xwnt-8 is involved in the specification of lateral (somitogenic) mesoderm and BMP-4 in the specification of ventral mesoderm.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Patterning
  • Bone Morphogenetic Protein 4
  • Bone Morphogenetic Proteins / metabolism*
  • DNA-Binding Proteins*
  • Gastrula / metabolism
  • Gene Expression Regulation, Developmental* / drug effects
  • In Situ Hybridization
  • Lithium Chloride / pharmacology
  • Mesoderm / drug effects
  • Mesoderm / physiology*
  • Muscle Proteins / metabolism
  • Myogenic Regulatory Factor 5
  • Proteins / metabolism
  • Proto-Oncogene Proteins / metabolism*
  • RNA / metabolism
  • Signal Transduction
  • Time Factors
  • Trans-Activators*
  • Transcription, Genetic
  • Wnt Proteins
  • Xenopus
  • Xenopus Proteins*
  • Zebrafish Proteins*

Substances

  • Bone Morphogenetic Protein 4
  • Bone Morphogenetic Proteins
  • DNA-Binding Proteins
  • Muscle Proteins
  • Myf5 protein, Xenopus
  • Myogenic Regulatory Factor 5
  • Proteins
  • Proto-Oncogene Proteins
  • Trans-Activators
  • Wnt Proteins
  • Xenopus Proteins
  • Zebrafish Proteins
  • bmp4 protein, Xenopus
  • bmp4 protein, zebrafish
  • szl protein, Xenopus
  • wnt8a protein, Xenopus
  • RNA
  • Lithium Chloride