... expression of GSC, chordin , and HNF-3 β, which is quickly followed by the appearance of the primitive streak in the epiblast ( Izpisúa-Belmonte et al., 1993 ; Kispert et al., 1995 ; Streit et al., 1998 ). To analyze the duration of LiCl sensitivity we treated embryos up to the stage of head...

... the gastrula stage, at which time expression is confined to ventral and lateral cells of the marginal zone of the zebrafish embryo. Later, eve1 transcripts are located in the most posterior part of the extending tail tip. We show that LiCl, known to dorsalize Xenopus embryos, has the same effect in zebrafish...

... when cells are becoming committed to defined fates. Exposure of early embryos to LiCl, which shifts posterior cells to more anterior fates, reduces the abundance of this posterior-specific transcript. In contrast, embryos ventralized by u.v. treatment express normal levels of the transcript, implying...