In zebrafish, germ cells are responsible for transmitting the genetic information from one generation to the next. During the first cleavages of zebrafish embryonic development, a specialized part of the cytoplasm known as germ plasm, is responsible of committing four blastomeres to become the progenitors of all germ cells in the forming embryo. Much is known about how the germ plasm is spatially distributed in early stages of primordial germ cell development, a process described to be dependant on microtubules ...

By the end of the first day of embryonic development, zebrafish primordial germ cells (PGCs) arrive at the site where the gonad develops. In our study we investigated the mechanisms controlling the precision of primordial germ cell arrival at their target. We found that in contrast with our expectations which were based on findings in Drosophila and mouse, the endoderm does not constitute a preferred migration substrate for the PGCs. Rather, endoderm derivatives are important for later stages of organogenesis ...