Expression pattern of hematopoietic genes in X tropicalis. Whole-mount in situ hybridization analysis of cebpa, spib, scl, fli1, mpo, csfr1, spi1, lcp, mmp7, and globin at stage 12, 15, 18, 23, and 26. Expression of cebpa was first detected at stage 12 in dorsal anterior mesoderm (and see supplemental Figure 1). From stage 15 until the end of neurulation, cebpa was expressed in the aVBI. Shortly after, cebpa-positive cells showed a punctate pattern throughout the embryo. A indicates anterior view; D, dorsal view; L, lateral view (anterior is to the left and dorsal to the top); and V, ventral view (anterior is to the left).