Twisted gastrulation is required for forebrain specification and cooperates with Chordin to inhibit BMP signaling during X. tropicalis gastrulation

Dev Biol. 2006 Jan 1;289(1):166-78. doi: 10.1016/j.ydbio.2005.10.022.

Abstract

In the developing vertebrate embryo, proper dorsal-ventral patterning relies on BMP antagonists secreted by the organizer during gastrulation. The BMP antagonist chordin has a complex interaction with BMPs that is governed in part by its interaction with the secreted protein twisted gastrulation (tsg). In different contexts, tsg has activity as either a BMP agonist or as a BMP antagonist. Using morpholino oligonucleotides in Xenopus tropicalis, we show that reducing tsg gene product results in a ventralized embryo, and that tsg morphants specifically lack a forebrain. We provide new evidence that tsg acts as a BMP antagonist during X. tropicalis gastrulation since the tsg depletion phenotype can be rescued in two ways: by chordin overexpression and by BMP depletion. We conclude that tsg acts as a BMP antagonist in the context of the frog gastrula, and that it acts cooperatively with chordin to establish dorsal structures and particularly forebrain tissue during development.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Bone Morphogenetic Proteins / metabolism
  • Down-Regulation
  • Embryo, Nonmammalian / drug effects
  • Embryo, Nonmammalian / embryology
  • Embryo, Nonmammalian / metabolism
  • Gastrula / metabolism
  • Glycoproteins / genetics
  • Glycoproteins / metabolism*
  • Intercellular Signaling Peptides and Proteins / genetics
  • Intercellular Signaling Peptides and Proteins / metabolism*
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Membrane Proteins / antagonists & inhibitors*
  • Molecular Sequence Data
  • Prosencephalon / drug effects
  • Prosencephalon / embryology*
  • Prosencephalon / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / pharmacology
  • Signal Transduction
  • Xenopus / embryology*
  • Xenopus / genetics
  • Xenopus / metabolism
  • Xenopus Proteins / antagonists & inhibitors*
  • Xenopus Proteins / genetics
  • Xenopus Proteins / metabolism*

Substances

  • Bone Morphogenetic Proteins
  • Glycoproteins
  • Intercellular Signaling Peptides and Proteins
  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • RNA, Messenger
  • TWSG1 protein, Xenopus
  • Xenopus Proteins
  • bambi-A protein, Xenopus
  • chordin