Fig. S2

foxc1b:EGFP mRNA overlaps with acta2 expression in vascular smooth muscle cells. A-C) 2 dpf images and D-L) 4 dpf images. A) foxc1b mRNA expressing-cells are adjacent to kdrl:EGFP positive endothelium (brown, arrowheads). B) foxc1b mRNA (green) is detected adjacent to kdrl:EGFP antibody stain (red) in the aortic arch arteries. C) foxc1b mRNA is expressed in the ceratohyal. D) foxc1b mRNA expressing-cells are adjacent to the endothelium (arrowheads). E) foxc1b mRNA is in mural cells adjacent to kdrl:EGFP antibody stain (red) in the aortic arch arteries (arrowheads). F) foxc1b mRNA is observed in mural cells adjacent to the ventral aorta (arrowheads). G-L) At 4 dpf, foxc1b mRNA and acta2:EGFP (brown) are co-expressed in mural cells in the aortic arch arteries and brain vessels. Enlargements shown in J, K, and L. H) foxc1b mRNA is co-expressed with acta2:EGFP antibody stain (red) in the aortic arch arteries (arrowheads). I) foxc1b mRNA is co-expressed with acta2:EGFP around the ventral aorta (arrowheads). J) Enlargement of the ventral head in G shows overlap of foxc1b mRNA and acta2:EGFP on the aortic arch arteries (arrow). K) In the brain, there is overlap of foxc1b mRNA and acta2:EGFP (arrows). L) Enlargement of panel K, showing the overlap between foxc1b mRNA and acta2:EGFP, but also that foxc1b mRNA is expressed in smaller vessels distal to the termination point of acta2:EGFP (asterisks). Scale bars in A, D, J represent 20 µm. Scale bars in B, C, E, F, H, I represent 50 µm. Scale bar in G represents 100 µm. AAA = aortic arch arteries, CH = ceratohyal, VA = ventral aorta.