title: Truncated type II receptor for BMP-4 induces secondary axial structures in Xenopus embryos.
abstract: BRK-3 is a vertebrate type II receptor for BMP-4 distantly related to invertebrate type II receptors for BMP-2/BMP-4/dpp, such as daf-4 and punt. BRK-3 has a long carboxy-terminal sequence following intracellular kinase domain and is capable of forming a high-affinity complex with a type I receptor, BRK-2. To examine the role of BRK-2 + BRK-3 receptor complex in BMP signaling during early embryogenesis, the dominant-negative form of BRK-3 was ectopically expressed in the Xenopus embryos. A secondary body axis expressing the Sonic hedgehog and N-CAM genes is induced by injecting mRNA encoding truncated form of BRK-3 into ventral marginal region, implicating the BMP signaling in axial mesoderm induction. Formation of the secondary axis depends on whether the deletion extends into the kinase domain, not into the carboxy-terminal tail, suggesting that the kinase domain, but not the tail region, is essential for BMP signaling.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D052006:Bone Morphogenetic Protein Receptors, Type II; D019485:Bone Morphogenetic Proteins; D018076:DNA, Complementary; D004625:Embryo, Nonmammalian / Q000502:physiology*; D005347:Fibroblasts / Q000378:metabolism; D015723:Gene Library; D006133:Growth Substances / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D010802:Phylogeny; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis / Q000737:chemistry / Q000502:physiology*; D011506:Proteins / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000502:physiology; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D012867:Skin / Q000378:metabolism*; D014982:Xenopus laevis
chemical_list: D019485:Bone Morphogenetic Proteins; D018076:DNA, Complementary; D006133:Growth Substances; D011506:Proteins; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins; D017346:Protein Serine-Threonine Kinases; C498218:BMPR2 protein, human; D052006:Bone Morphogenetic Protein Receptors, Type II