Expression of hematopoietic genes in gata1 mutant embryos by whole-mount RNA in situ hybridization and qRT-PCR. Lateral views of embryos with the tails to the left and dorsal to the top. (A) In situ hybridization showing the differential expression pattern of the erythroid markers band3, α-globin embryonic forms 1 (αe1) and 2 (αe2), draculin, and gata1 in 15-18 somites gata1^T301K/vlt (band3, n = 16/16; globins, n = 6/6; draculin, n = 5/5; gata1, n = 9/9), gata1^vlt/vlt (band3, n = 8/8; globins, n = 6/6; draculin, n = 5/5; gata1, n = 8/8) and wild-type (band3, n = 6/6; globins, n = 10/10; draculin, n = 13/13; gata1, n = 10/10) embryos. Original magnification ×80. Individual embryos were imaged and genotyped by PCR followed by Taq1 digestion (vlt) or sequencing (T301K). (B) qRT-PCR of Gata1 target genes band3 and βe2 in 40 hpf wild-type, gata1^+/T301K, gata1^T301K/T301K, and gata1^vlt/vlt embryos. Data represents fold change in expression relative to gata1^vlt/vlt. Twenty embryos from each genotype were pooled for RNA extraction and qRT-PCR.