Zebrafish were injected with morpholinos as indicated, and scored at 14 som for etsrp⁺ angioblast positioning. Numbers in parentheses indicate the total number scored, and the incidence of each possible phenotype is given as a percentage of all scored embryos. Criteria: Embryos were scored as normal if there was evidence of a nascent midline vascular cord; mildly affected if midline angioblasts were sparse or absent; severely affected if individual angioblasts appeared lateral to the main row (ie, wrong direction); and toxic if the entire embryo appeared to be adversely affected.

ECSCR indicates endothelial-cell specific chemotaxis receptor.

Significant differences of observed distributions are indicated as follows: *P < .001 versus cMO injected;

P < .001 versus MO2 10 ng injected, using χ² test excluding embryos scored as toxic.