Dorsoventral Patterning in the Zebrafish: Bone Morphogenetic Proteins and Beyond

Abstract

Lineage tracing studies carried out in amphibian, fish, mouse and chicken embryos have shown that the fate of cells in the older animal can be traced to the positions of their precursors at pre- or early-gastrula stages of development, which allowed the design of fate maps of vertebrate embryos (Dale and Slack 1987; Kimmel et al. 1990; Hatada and Stern 1994; Lawson 1999). The fate map of the zebrafish gastrula is shown in Fig. 3A. Despite the different architectures of the embryos, the fate maps of the different vertebrate species show high similarities, pointing to conserved mechanisms of early embryonic patterning, which defines positional values within the early embryo. One of the primary systems providing positional information is the genetic network controlling early dorsoventral (DV) patterning, most intensely studied in frog and fish.