The zebrafish (Danio rerio) is a powerful model organism for the study of vertebrate biology,
being well suited to both developmental and genetic analysis. Large-scale genetic screens …

Vertebrate gastrulation involves the specification and coordinated movement of large
populations of cells that give rise to the ectodermal, mesodermal and endodermal germ …

The concept of modularity is fundamental to research in both evolutionary and
developmental biology, though workers in each field use the idea in different ways. Although …

All vertebrates display a characteristic asymmetry of internal organs with the cardiac apex,
stomach and spleen towards the left, and the liver and gall bladder on the right 1, 2, 3. Left …

The Human Genome Project is in full swing, and every day we know more of the sequences
that define us (Burris et al. 1998). Some smaller bacterial genomes are already sequenced …

We have identified and characterized a zebrafish recessive maternal effect mutant, ichabod,
that results in severe anterior and dorsal defects during early development. The ichabod …

The pitx2 gene is a member of the bicoid-homeodomain class of transcription factors that
has been implicated in the control of left-right asymmetry during organogenesis. Here we …

We identified a zebrafish homologue of Dickkopf-1 (Dkk1), which was previously identified in
Xenopus as a Wnt inhibitor with potent head-inducing activity. Zebrafish dkk1 is expressed …

mRNA injection into the ventral blastomeres of Xenopus embryos of mRNA encoding Wnt
pathway genes induces a secondary axis with complete head structures. To identify target …

Nodal-related signals comprise a subclass of the transforming growth factor-β (TGF-β)
superfamily and regulate key events in vertebrate embryogenesis, including mesoderm …