Figure 6
From: Knockout of ERK5 causes multiple defects in placental and embryonic development
Morphology of wild type and ERK5 -/- mutant yolk sacs. Embryos were isolated from timed matings of ERK5+/- mice and photographed. Embryos were then genotyped by PCR analysis of the isolated yolk sac. At E9.75 (A) wild type and ERK5-/- mutant yolk contain blood islands (arrow). By E10.25 (B), the blood vessels found in wild type yolk sacs formed distinct large vessels which branched down into smaller vessels (arrow). In contrast, the surfaces of the ERK5-/- yolk sacs became pale, and did not show the branched blood vessels. At E11.5 (C), ERK5-/- yolk sacs appeared intermittent with diffuse patches of red blood cells (arrow). The ERK5-/- embryos showed were pale and apparently devoid of blood circulation without a beating heart.