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Updated: Jun 26, 2026

Tissue Determination Using the Animal Cap Transplant (ACT) Assay in Xenopus laevis
Published on: May 17, 2010
Xenopus chordin: a novel dorsalizing factor activated by organizer-specific homeobox genes
Y Sasai1, B Lu, H Steinbeisser
1Molecular Biology Institute, University of California, Los Angeles 90024-1737.
Abstract:
A Xenopus gene whose expression can be activated by the organizer-specific homeobox genes goosecoid and Xnot2 was isolated by differential screening. The chordin gene encodes a novel protein of 941 amino acids that has a signal sequence and four Cys-rich domains. The expression of chordin starts in Spemann's organizer subsequent to that of goosecoid, and its induction by activin requires de novo protein synthesis. Microinjection of chordin mRNA induces twinned axes and can completely rescue axial development in ventralized embryos. This molecule is a potent dorsalizing factor that is expressed at the right time and in the right place to regulate cell-cell interactions in the organizing centers of head, trunk, and tail development.
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