Fig. 5. The regulatory modules of Hr-Otx are capable of directing line-specific transcription in Ciona intestinalis embryos. The reporter constructs containing regulatory modules #2 (A), #3 (B), #4 (C,D), #5 (E,E') and #6 (F) were electroporated into Ciona fertilized eggs, and the resulting embryos were examined for lacZ transcripts at the 64-cell (A-C,E,E',F) or 76-cell (D) stage. Animal (A,E) and vegetal (B-D,E',F) views are shown. Shown below the images are the identity of the lacZ-expressing cell line in the Ciona embryo and a schematic representation of the in situ hybridization specimen. (G,H) Frequency of lacZ-positive cells for a given cell line in 64-cell (G) or 76-cell (H) embryos injected with reporter constructs harboring the regulatory modules indicated on the left side. For color codes, see Fig. 1.