Required for lymphangioblast budding and angiogenic sprouting from venous endothelium during embryogenesis. Necessary for lymphangiogenesis, but is probably not part of either the vegfc-vegfr3 signaling or sox18-prox1 transcriptional pathways. Not expressed in blood or lymphatic endothelial cells, correlating spatially and temporally with the migration routes of endothelial cells that bud from the PCV, migrate in association with somite boundaries and seed the horizontal myoseptum region from where lymphatic precursors later migrate. Restricted expression during development with expression in the pronephros and ventral mesenchyme at 24 hours post fertilization (hpf). By 36 hpf, expression is detected in discrete zones along each somitic boundary, between the PCV and the horizontal myoseptum, as well as along the horizontal myoseptum itself. At 48 hpf, expression is restricted along the horizontal myoseptum. Belongs to the CCBE1 family.