Table 1. Etv2 Function Is Required at Earlier Stages for Arterial grl Expression and at Later Stages for Venous mrc1 Expression.

grl Expression, 24 hpf	Normal Dorsal Aorta	Reduced/Fragmented Dorsal Aorta	Absent Dorsal Aorta	Number of Embryos
Control uninjected	100%	0	0	40
Etv2 MO uncaged at 30% epiboly	0	4% ± 4%	96% ± 4%	30
7-somite	65% ± 15%	35% ± 15%	0	23
13- to 14-somite	92% ± 2%	8% ± 2%	0	24
16- to 17-somite	100%	0	0	23
Never uncaged	100%	0	0	25

mrc1 Expression, 24 hpf	Normal Cardinal Vein	Reduced Cardinal Vein	Absent Cardinal Vein	Number of Embryos
Control uninjected	100%	0	0	40
Etv2 MO uncaged at 30% epiboly	0	0	100%	30
7-somite	0	100%	0	30
13- to 14-somite	33% ± 4%	67% ± 4%	0	25
16- to 17-somite	33% ± 8%	67% ± 8%	0	19
Never uncaged	88% ± 9%	12% ± 9%	0	40

Data represent an average from two independent experiments. grl and mrc1 expression analyzed at 24 hpf ± refers to the SE.