Cellular and molecular mechanisms of convergence and extension in zebrafish.

Cellular and molecular mechanisms of convergence and extension in zebrafish. Curr Top Dev Biol. 2020;136:377-407 Authors: Williams MLK, Solnica-Krezel L Abstract Gastrulation is the period of development when the three germ layers, mesoderm, endoderm and ectoderm, are not only formed, but also shaped into a rudimentary body plan. An elongated anteroposterior (AP) axis is a key feature of all vertebrate body plans, and it forms during gastrulation through the highly conserved morphogenetic mechanism of convergence & extension (C&E). As the name suggests, this process requires that cells within each germ layer converge toward the dorsal midline to narrow the tissue in the mediolateral (ML) dimension and concomitantly extend it in the AP dimension. In a number of vertebrate species, C&E is driven primarily by mediolateral intercalation behavior (MIB), during which cells elongate, align, and extend protrusions in the ML direction and interdigitate between their neighbors. MIB is only one of many complex cellular mechanisms that contributes to C&E in zebrafish embryos, however, where a combination of individual cell migration, collective migration, random walk, radial intercalation, epiboly movements, and MIB all act together to shape the nascent germ layers. Each of these diverse cell movements is driven by a distinct suite of dynamic cellular properties/activities, such as actin-rich protrusions, myosin contractility, an...
Source: Current Topics in Developmental Biology - Category: Biology Authors: Tags: Curr Top Dev Biol Source Type: research