Fig. 5.

A revised origin of Ciona photoreceptor cells. (A, B) Control and ZicL > dnFGFR embryos were co-electroporated with reporters for Six3/6 and Arrestin, and then grown to larval stage. (A) Arrestin reporter labels a cluster of cells surrounding the ocellus, posterior to the Six3/6 expression domain. (B) Inhibition of FGF signaling results in posterior expansion of the Six3/6 reporter, but no significant change in Arrestin reporter expression. Arrestin reporter does not colocalize with ectopic Six3/6 reporter. (C, C′) Embryos were co-electroporated with reporters for Dmrt and Arrestin and grown to larval stage. Clusters of Arrestin+ cells are consistently observed posterior to the Dmrt expression domain. Scale bars = 50 µm.