Xenopus frizzled 4 is a maternal mRNA and its zygotic expression is localized to the neuroectoderm and trunk lateral plate mesoderm

We describe the identification and expression pattern of Xenopus frizzled 4 (Xfz4) gene during early development. Xfz4 protein presents characteristic features of a frizzled family member. The mature protein sequence of Xfz4 is 93% identical to murine Mfz4. Xfz4 is a maternal mRNA, its expression le vel remains constant during early development. The mRNA is first localized during gastrulation to the dorsal presumptive neuroectoderm. At the end of gastrulation, Xfz4 mRNA is detected in the dorso-anterior neuroectoderm. Du ring neurulation, Xfz4 mRNA is expressed as a band on both side of the fore brain, and in the trunk lateral plate mesoderm. As development proceeds, ex pression of Xfz4 mRNA in the trunk lateral plate mesoderm decreases but per sists in the forebrain. It is also expressed in the posterior unsegmented s emitic mesoderm from late tail-bud stage onward. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.