Genetic interaction of the tbx16, plcγ1, and notch signaling pathways for the induction of HSCs. Whole-mount in situ hybridization of embryos between 36 and 40 hpf. Embryo manipulation, genotype, and probes used are described for each panel. Red arrowheads denote arterial expression of HSC markers. Lateral views, anterior left; low magnification (original magnification ×10) and higher magnification (original magnification ×40) of the trunk region. After heat shock (“Methods”), NICD expands c-myb and runx1 expression in wild-type embryos (A,B). NICD rescues c-myb and runx1 expression in tbx16 morphants (C-F) and plcγ1 morphants (G-J).