Transcriptional regulation of Xvent homeobox genes

Mech Dev. 1999 Mar;81(1-2):139-49. doi: 10.1016/s0925-4773(98)00239-1.


The Xvent homeobox multigene family is essential for the patterning of the ventral mesoderm in Xenopus embryos. We have identified two novel members of this family, Xvent-1B and Xvent-2B, and have characterized their genomic structures. These two genes show a clustered organization and have probably arisen by gene duplication with subsequent inversion. Cis-regulatory elements within the promoters of both genes have been identified which contribute to their spatial activation. Xvent-2B is activated by BMP-2/4 in the absence of de novo protein synthesis, suggesting that this gene is a direct target of BMP-signalling. In contrast, Xvent-1B does not directly respond to BMP-2/4, but is activated by Xvent-2B. This activation is documented by Xvent-1B promoter/reporter studies, Xvent-2B overexpression and loss-of-function analysis using a dominant-negative Xvent-2 mutant. However, cycloheximide experiments reveal that Xvent-2B by itself is not sufficient to activate transcription of the Xvent-1B gene, but that there is a requirement for additional factor(s) being synthesized after midblastula transition.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bone Morphogenetic Protein 2
  • Bone Morphogenetic Protein 4
  • Bone Morphogenetic Proteins / metabolism
  • Cycloheximide / pharmacology
  • Epistasis, Genetic
  • Genes, Dominant
  • Genes, Regulator / physiology*
  • Genomic Library
  • Homeodomain Proteins / genetics*
  • In Situ Hybridization
  • Luciferases / metabolism
  • Molecular Sequence Data
  • Mutagenesis
  • Phenotype
  • Promoter Regions, Genetic
  • Protein Synthesis Inhibitors / pharmacology
  • Recombinant Fusion Proteins
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Homology, Amino Acid
  • Sequence Homology, Nucleic Acid
  • Tissue Distribution
  • Transcription Factors*
  • Transforming Growth Factor beta*
  • Xenopus Proteins*


  • Bone Morphogenetic Protein 2
  • Bone Morphogenetic Protein 4
  • Bone Morphogenetic Proteins
  • Homeodomain Proteins
  • Protein Synthesis Inhibitors
  • Recombinant Fusion Proteins
  • Transcription Factors
  • Transforming Growth Factor beta
  • Xenopus Proteins
  • bmp4 protein, Xenopus
  • ventx1.2 protein, Xenopus
  • ventx2.1 protein, Xenopus
  • Cycloheximide
  • Luciferases

Associated data

  • GENBANK/AJ131094
  • GENBANK/AJ131095