(A) Wild type embryos exhibiting expression of glcci1, kiaa0650, krcp in blood cells in the posterior mesoderm at 5 somites (dorsal view, left panels), in the ICM blood cells at 24 hpf (lateral view, middle panels), and in circulating blood cells in the vessels and over the yolk (arrowheads, lateral view, right panels). (B) Flat mount images of embryos are oriented with anterior on the left and posterior on the right. Expression of gata1 (100%, n=9), glcci1 (100%, n=7), kiaa0650 (100%, n=3), and krcp (100%, n=6) was lost in sptb104 mutant embryos compared with wild-type and heterozygous siblings at 12 somites. Expression of scl (100%, n=5) and gata2 (100%, n=7) was present but disorganized in putative angioblasts of sptb104 mutant embryos compared with wild-type and heterozygous siblings. (C) At 18 somites, normal expression of glcci1 (5/27), kiaa0650 (7/37), and krcp (6/27) in ICM blood cell precursors of wild-type and heterozygous siblings was virtually absent in montg234 mutant embryos. Numbers in parentheses represent the number of embryos lacking blood expression out of total number of embryos in an incross clutch.