Expression of cell adhesion molecule E-cadherin in Xenopus embryos begins at gastrulation and predominates in the ectoderm.

Abstract

Abstract. The expression of the Ca2÷-dependent epithelial cell adhesion molecule E-cadherin (also known as uvomorulin and L-CAM) in the early stages of embryonic development of Xenopus laevis was examined. E-Cadherin was identified in the Xenopus A6 epithelial cell line by antibody cross-reactivity and several biochemical characteristics. Four independent mAbs were generated against purified Xenopus E-cadherin. All four mAbs recognized the same polypeptides in A6 cells, adult epithelial tissues, and embryos. These mAbs inhibited the formation of cell contacts between A6 cells and stained the basolateral plasma membranes of A6 ceils, hepatocytes, and alveolar epithelial cells. Xenopus blastomeres. Detectable accumulation of E-cadherin started just before gastrulation at stage 91/2 and increased rapidly up to the end of gastrulation at stage 15. In stage 15 embryos, specific immunofluorescence staining of E-cadherin was discernible only in ectoderm, but not in mesoderm and endoderm. The ectoderm at this stage consists of two cell layers. The outer cell layer of ectoderm was stained intensely, and staining was localized to the basolateral plasma membrane of these cells. Lower levels of staining were observed in the inner cell layer of ectoderm. The coincidence of E-cadherin expression with the process of gastrulation and its restriction to the ectoderm indicate that it may play a role in the morphogenetic movements of gastrulation and resulting segregation of embryonic germ layers.

Zebrafish E‐cadherin: Expression during early embryogenesis and regulation during brain development

“…E-cadherin is essential for early embryogenesis in mouse (Larue et al, 1994;Riethmacher et al, 1995). Detailed analysis of E-cadherin expression in embryogenesis was described for mouse, chick, and Xenopus (Broders et al, 1993;Choi and Gumbiner, 1989;Hirai et al, 1989a,b;Levi et al, 1991;Shimamura and Takeichi, 1992;Shimamura et al, 1994;Takeichi, 1988;Thiery et al, 1984). E-cadherin expression in the ectoderm is downregulated during neurulation (Takeichi, 1988).…”

“…E-cadherin expression in the ectoderm is downregulated during neurulation (Takeichi, 1988). However, discrete regions of E-cadherin expression are activated in the developing and adult brain (Choi and Gumbiner, 1989;Shimamura and Takeichi, 1992;Shimamura et al, 1994;Thiery et al, 1984). The functional significance of neural E-cadherin expression is unclear.…”

“…In the mouse and chick but not in Xenopus, E-cadherin is expressed in the MHB (Choi and Gumbiner, 1989;Shimamura and Takeichi, 1992;Shimamura et al, 1994;Thiery et al, 1984). In zebrafish, mutations in the Pax2.1 gene (no isthmus or noi) and in the Fgf8 gene (acerebellar or ace) disrupt MHB development (Brand et al, 1996).…”

Mechanisms driving neural crest induction and migration in the zebrafish andXenopus laevis

“…22,160 The predominant cadherin in the early Xenopus embryo is C-cadherin; 162 beginning in the late blastula an E-cadherin-like molecule is expressed in the developing epidermis and is absent from the developing neural plate. 163,164 Beginning at gastrulation, cadherin-11 is expressed in a Wnt-dependent manner; 165 later it is expressed in migrating neural crest cells, 166 together with the protocadherin PCNS 167 and N-cadherin. 168 Functional studies of cadherin-11 indicate that its overexpression, or the overexpression of a mutant polypeptide missing its cytoplasmic b-catenin binding domain, blocks cranial neural crest migration and leads to their neural differentiation.…”

Control of somitic expression of tenascin in Xenopus embryos by myogenic factors and Brachyury

“…Specificity of the monoclonal antibody 12/101 for muscle has been described by Kintner and Brockes (1984). Anti-E-cadherin antibodies are a mixture of monoclonal antibodies 8C2, 5D3, and 19A2 (Choi and Gumbiner, 1989). Goat anti-rabbit IgGs conjugated to fluorescein isothiocyanate (FITC) and goat anti-mouse IgGs conjugated to tetramethylrhodamine isothiocyanate (TRITC), were purchased from Biosys (Compiegne, France) and Sigma, respectively.…”