A novel Xenopus homologue of bone morphogenetic protein-7 (BMP-7).
We identified a Xenopus gene closely related to mammalian bone morphogenetic protein (BMP)-7 (also termed osteogenic protein-1 or OP-1). It resembles the mammalian gene in primary structure and expression pattern much more closely than does a previously described Xenopus homologue, originally termed XBMP-7 [Nishimatsu, Suzuki, Shoda, Murakami and Ueno (1992) Biochem. Biophys. Res. Commun. 186, 1487-1495]. The novel gene has therefore been designated XBMP-7 and the gene described earlier has been renamed XBMP-7R (M. Moos and N. Ueno, unpublished work). It has a broad distribution, primarily in the anterior and posterior ventral regions during gastrulation, subsequently becoming prominent at different stages in a wide variety of structures (eyes, neural structures, heart, pronephros, posterior ventral region and other structures), paralleling the distribution of XBMP-4 closely. However, its expression begins later than that of XBMP-4 during gastrulation. Lithium treatment of embryos concentrates the XBMP-7 expression in the expanded eye and heart structures. Ventral overexpression of XBMP-7 produces large protrusions that ultimately develop colouration characteristic of haemoglobin, which is confirmed by markedly expanded expression of alpha-globin. Dorsal overexpression suppresses dorsal anterior structures. Molecular analysis of animal caps overexpressing XBMP-7 reveals induction of markers associated with ventral and haematopoietic tissue, which is consistent with whole-embryo overexpression results. Globin induction by XBMP-7 can be blocked by a truncated BMP receptor previously shown to interrupt BMP-4 signalling, indicating XBMP-7 also interacts with this receptor. Our data support the concept that XBMP-7 may play a variety of roles during embryogenesis, and suggest a possible role in haematogenesis.
Laboratory of Developmental Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Rockville, MD 20852-1448, USA.
S
S
Wang
M
M
Krinks
L
L
Kleinwaks
M
M
Moos
D000595:Amino Acid Sequence; D000818:Animals; D055419:Bone Morphogenetic Protein 7; D052004:Bone Morphogenetic Protein Receptors; D019485:Bone Morphogenetic Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018076:DNA, Complementary; D004625:Embryo, Nonmammalian / Q000378:metabolism*; D047108:Embryonic Development; D004627:Embryonic Induction; D018507:Gene Expression Regulation, Developmental; D005914:Globins / Q000032:analysis; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D017403:In Situ Hybridization; D008648:Mesoderm / Q000166:cytology; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D011956:Receptors, Cell Surface / Q000378:metabolism; D017978:Receptors, Growth Factor; D016212:Transforming Growth Factor beta; D014981:Xenopus / Q000033:anatomy & histology / Q000196:embryology / Q000235:genetics*; D029867:Xenopus Proteins
D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D018076:DNA, Complementary; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D017978:Receptors, Growth Factor; D016212:Transforming Growth Factor beta; D029867:Xenopus Proteins; C525822:bmp7.1 protein, Xenopus; D005914:Globins; D052004:Bone Morphogenetic Protein Receptors