Fig. 5.

An atlas of YP consumption during early frog embryogenesis. (A) The percentage of Seryp^- YPs in each of the tissues and stages depicted, as well as from unfertilized eggs and mid-neurulae (stage 17/18), was quantified. See supplementary material Table S2 for all numbers. For illustrative purposes, tissues (most of which are strictly internal) are approximately located on drawings (Nieuwkoop and Faber, 1994). The average ±1 s.d. of at least three embryos descended from different female frogs is presented. (B)Seryp^- (%) was plotted, using the most relevant tissues present at each stage. For instance, somites at stage 27 were most related to the somitogenic mesoderm at stage 14, to the dorsal lip at stage 12, and to the marginal zone of stage 9 embryos and eggs. (C) Activated YPs that have no detectable Seryp are apparent in multiple tissues in early neurulae (blue arrows). A transverse section of an early neurula (top, scale bar: 100 μm) locates tissues (yellow boxes) immunostained with anti-Vtg and anti-Seryp and imaged by confocal microscopy (bottom, scale bars: 10 μm).