(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.

Fig. 1. ERK is activated transiently in the PMC precursors a few hours after
zygotic expression of ets1. (A-E) In situ hybridization with an
ets1 probe. (B-D) Starting at the early blastula stage up to the
mesenchyme blastula stage, ets1 expression is restricted to the PMCs
(arrow in D). (E) At the end of gastrulation, ets1 transcripts are
also enriched in the SMCs (arrow). (F-N) Whole-mount immunolocalization of
activated ERK using an anti-MAPK-P antibody. (A) Sixty-cell stage, (F) early
blastula, (B,C) prehatching blastula, (G,H) hatching blastula, (I,J) early
mesenchyme blastula, (D,K) mesenchyme blastula, (L,M) early gastrula (arrows
in M indicate staining in the ectoderm adjacent to the PMC clusters) and
(E,N,O) late gastrula. (O) Control embryo stained with the secondary antibody
alone. All the embryos are viewed from the side with the animal pole at the
top except when mentioned: av, animal view; vv, vegetal view.