HrWnt-5: a maternally expressed ascidian Wnt gene with posterior localization in early embryos.
Ascidians show a highly determinate mode of development. In particular, components of the posterior-vegetal cytoplasm of fertilized eggs are responsible for the establishment of the embryonic axis. Recent studies have, however, also revealed significant roles of cell-cell interactions during embryogenesis. Proteins encoded by the Wnt family of genes act as signals and have been shown to play important roles in a wide range of developmental processes. Here we have isolated and characterized an ascidian Wnt gene, HrWnt-5, from Halocynthia roretzi. HrWnt-5 mRNA is present in the vegetal cortex in unfertilized eggs. After fertilization, HrWnt-5 mRNA moves to the equatorial region to form a crescent-like structure, after which the mRNA is concentrated in the posteriormost region of the embryo. This early pattern of HrWnt-5 mRNA localization coincides with another posterior-vegetally localized mRNA, pem, isolated from Ciona savignyi. In the gastrula, the zygotic HrWnt-5 mRNA is found in a variety of blastomeres, suggesting multiple roles of the gene.
Sasakura
Y
Y
Department of Zoology, Graduate School of Science, Kyoto University, Japan.
Ogasawara
M
M
Makabe
K W
KW
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001757:Blastomeres / Q000737:chemistry; D016764:Cell Polarity; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004527:Egg Proteins / Q000235:genetics*; D005775:Gastrula / Q000737:chemistry; D018628:Gene Dosage; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D005796:Genes / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000032:analysis; D014561:Urochordata / Q000196:embryology* / Q000235:genetics*; D051153:Wnt Proteins
D018076:DNA, Complementary; D004527:Egg Proteins; D012333:RNA, Messenger; D051153:Wnt Proteins; C114699:Wnt-5 protein, Halocynthia roretzi