Nuclear localization of beta-catenin in vegetal pole cells during early embryogenesis of the starfish Asterina pectinifera.
Recently, beta-catenin has been reported to control the expression of morphogenetic genes through the Wnt signaling pathway in invertebrate embryogenesis. In this study, the distribution pattern of beta-catenin during starfish embryogenesis was investigated using immunohistochemistry. In 16-cell stage embryos, beta-catenin began to accumulate in some nuclei at the vegetal pole. During the early cleavage stage, the cells expressing nuclear beta-catenin increased in number in the vegetal pole region of the embryos, and the beta-catenin signal increased in intensity in each nucleus. At the blastula stage, signal for beta-catenin was also found in the cytoplasm of the cells with nuclear beta-catenin. At the vegetal plate stage, almost all vegetal plate cells expressed beta-catenin in both the nucleus and cytoplasm. When the embryos developed to early gastrulae, cells with nuclear beta-catenin were restricted to the archenteron tip, and the signal gradually faded in later stages. The localization and temporal change of beta-catenin expression suggests that beta-catenin has a pivotal role in archenteron formation in starfish embryos.
Miyawaki
Kyojy
K
Ushimado Marine Laboratory, Okayama University, Ushimado, Okayama 701-4303, Japan. gastrula@mx3.tiki.ne.jp
Yamamoto
Masamichi
M
Saito
Kyoko
K
Saito
Shouichiro
S
Kobayashi
Naoto
N
Matsuda
Seiji
S
D000818:Animals; D002467:Cell Nucleus / Q000648:ultrastructure*; D003598:Cytoskeletal Proteins / Q000032:analysis*; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000502:physiology*; D005306:Fertilization; D007150:Immunohistochemistry; D009024:Morphogenesis; D013215:Starfish / Q000196:embryology*; D015534:Trans-Activators / Q000032:analysis*; D051176:beta Catenin
D003598:Cytoskeletal Proteins; D015534:Trans-Activators; D051176:beta Catenin