FoxJ1 from T. adhaerens and S. purpuratus are nuclear localized and can regulate the expression of ciliary genes.

Anti-myc antibodies were used to detect Placozoa (A) and sea urchin (B) FoxJ1 (red, white arrow). Nuclei were stained with DAPI (blue). (C) Expression of dynein intermediate chain in the spinal cord (long arrow) and pronephric (kidney) duct (short arrow) of a wild-type zebrafish embryo. The wdr78 and efhc1 genes are expressed in a similar pattern in wild-type embryos (see Figure 2A and data not shown). Ectopic expression of dynein intermediate chain in embryos ectopically expressing placozoan (D) and sea urchin (E) FoxJ1, respectively. Ectopic expression of wdr78 in embryos ectopically expressing placozoan (F) and sea urchin (G) FoxJ1, respectively. Ectopic expression of efhc1 in embryos ectopically expressing placozoan (H) and sea urchin (I) FoxJ1, respectively. Mis-expression of the different ciliary genes in D–I is indicated by the arrows. Embryos depicted are at 20 hpf, oriented anterior to the left, dorsal to the top.

Zebrafish FoxJ2 and FoxJ3 are unable to induce the expression of ciliary genes.

(A) Expression of efhc1 in the spinal cord (long arrow) and pronephric (kidney) duct (short arrow) of a wild-type zebrafish embryo, and in embryos ectopically expressing zebrafish FoxJ2 (B) and FoxJ3 (C), respectively. (D) Expression of spag6 in the spinal cord (long arrow) and pronephric (kidney) duct (short arrow) of a wild-type zebrafish embryo, and in embryos ectopically expressing zebrafish FoxJ2 (E) and FoxJ3 (F), respectively. Embryos depicted are at 20 hpf, oriented anterior to the left, dorsal to the top.

Expression levels of invertebrate FoxJ1 proteins in zebrafish embryos. Western blot showing roughly equivalent levels of the zebrafish and sea urchin FoxJ1 proteins, but lower levels of expression of placozoan FoxJ1. Tubulin levels were measured as loading control.