Antimorphic PV.1 causes secondary axis by inducing ectopic organizer

Biochem Biophys Res Commun. 2002 Apr 12;292(4):1081-6. doi: 10.1006/bbrc.2002.6740.

Abstract

Xenopus homeobox gene, PV.1 ventralizes activin-induced dorsal mesoderm and inhibits neuralization of ectoderm in animal cap when overexpressed. Here we generated PV.1/engrailed fusion construct (N-PV1-EnR) to perform loss-of-function study for this transcription factor. N-PV1-EnR showed an extremely antimorphic effect, causing a partial secondary embryonic axis when expressed at ventral marginal zone of blastula. In ventral marginal zone cells, this chimeric protein induced organizer genes and suppressed ventral markers mimicking those effects reported for dominant negative BMP-4 receptor (DNBR). Moreover, N-PV1-EnR rescued the ventralized embryos caused by the ectopic dorsal expression of PV.1 but not by that of Xvent-2. These results suggested that PV.1 functions at downstream of BMP-4 as a ventralizing effector which acts separately from Xvent-2 and the dominant negative effect gained by this specific mutant is applicable for the further studies of BMP-4 downstream pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activin Receptors, Type I / genetics
  • Activin Receptors, Type I / metabolism
  • Animals
  • Body Patterning / drug effects
  • Body Patterning / physiology*
  • Bone Morphogenetic Protein Receptors, Type I
  • Embryo, Nonmammalian / drug effects
  • Embryo, Nonmammalian / embryology
  • Embryo, Nonmammalian / physiology
  • Embryonic Induction / drug effects
  • Genes, Dominant
  • Homeodomain Proteins / antagonists & inhibitors
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / pharmacology*
  • In Vitro Techniques
  • Microinjections
  • Organizers, Embryonic / drug effects
  • Organizers, Embryonic / metabolism*
  • Phenotype
  • Protein Serine-Threonine Kinases*
  • RNA, Messenger / administration & dosage
  • RNA, Messenger / genetics
  • Receptors, Growth Factor*
  • Recombinant Fusion Proteins / biosynthesis
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / pharmacology
  • Signal Transduction / drug effects
  • Signal Transduction / physiology
  • Transcription Factors*
  • Xenopus
  • Xenopus Proteins*

Substances

  • Homeodomain Proteins
  • RNA, Messenger
  • Receptors, Growth Factor
  • Recombinant Fusion Proteins
  • Transcription Factors
  • Xenopus Proteins
  • engrailed homeobox proteins
  • ventx1.1 protein, Xenopus
  • Protein Serine-Threonine Kinases
  • Activin Receptors, Type I
  • Bone Morphogenetic Protein Receptors, Type I