Expression of rigf, a member of avian VEGF family, correlates with vascular patterning in the developing chick limb bud.
In a differential display screening for genes regulated by retinoic acid in the developing chick limb bud, we have isolated a novel gene, termed rigf, retinoic-acid induced growth factor, that encodes a protein belonging to the vascular endothelial growth factor (VEGF) family. Rigf transcripts were found in the posterior region of the limb bud in a region-specific manner as well as in other embryonic tissues and regions, including the notochord, head and trunk mesenchyme, retinal pigment epithelium, and branchial arches. Several manipulations revealed that retinoic acid and sonic hedgehog signaling pathways regulate rigf expression in the limb bud. VEGF family members, which promote the migration, differentiation and proliferation of endothelial cells in both blood and lymphatic vessels, are important factors for the formation of blood and lymphatic vasculatures during development. We demonstrated that the anterior border of the rigf expression domain in the limb bud corresponds with the position of the primary central artery (the subclavian artery in the forelimb), which is a main artery for supplying blood to the limb. These observations taken together with results from some experimental manipulations suggest that the limb tissue attracts blood vessels into the limb bud and that rigf is involved in the pattern formation of blood vessels in the limb.
Tamura
Koji
K
Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai 980-8578, Japan. tam@biology.tohoku.ac.jp
Amano
Takanori
T
Satoh
Taeko
T
Saito
Daisuke
D
Yonei-Tamura
Sayuri
S
Yajima
Hiroshi
H
D000595:Amino Acid Sequence; D000818:Animals; D001158:Arteries / Q000196:embryology; D001808:Blood Vessels / Q000196:embryology*; D019521:Body Patterning / Q000235:genetics*; D002642:Chick Embryo; D003001:Cloning, Molecular; D004625:Embryo, Nonmammalian; D016228:Endothelial Growth Factors / Q000235:genetics* / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics; D018878:Limb Buds / Q000098:blood supply* / Q000196:embryology; D008222:Lymphokines / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D011784:Quail / Q000196:embryology; D017386:Sequence Homology, Amino Acid; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014212:Tretinoin / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; D036341:Intercellular Signaling Peptides and Proteins; D008222:Lymphokines; D015534:Trans-Activators; D014157:Transcription Factors; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D014212:Tretinoin