Fig. 3

Dorsalization of embryos in ism1 deletion mutants. a Schematic representation of upstream regulators of ism1 during various stages of embryonic development. b Schematic representation of the Ism1 protein and the amino acid length of its domains, signal sequence, Isthmin specific domain (ISD), thrombospondin-type 1 repeat (TSR), and an adhesion-associated domain in Muc4 and other proteins (AMOP). c Dorsalized and cyclopic phenotype observed in ism1 (∆N) mRNA-injected embryos at 24 hpf (see Table 1). d–g Dorsalization of the injected embryos at 50% epiboly, or late blastula (see Table 2). d, f Uninjected controls and e, g ism1(∆N)-injected embryos were probed for din and eve1 as dorsal and ventral markers, respectively. h, iboz appears unchanged after injection of ism1 (∆N). j, k, ndin, sqt, and fgf8 can be induced by ism1 (∆N) ectopically (arrowheads); l, m wnt8 (ORF1 + ORF2) is downregulated in the marginal zone. Left is ventral, and right is dorsal in all pictures. d–n Animal pole views. The time of color development is shortened in k to emphasize the ectopic up-regulation of sqt expression. Scale bar: 200 μm