One of conserved noncoding elements (CNEs) near the ET insertion site in pTME12 exhibited an enhancer activity.

<p><b>(A)</b> Distribution of CNEs in the region between <i>rhcga</i> and <i>kif7</i> in zebrafish genome. Genomic sequences between <i>rhcga</i> and <i>kif7</i> from zebrafish, fugu and medaka were subjected to VISTA browser and four CNEs were predicted in zebrafish genome as indicated (gray and red frame). The location of insertion site is marked with black arrow. <b>(B)</b> Schematic representation of pTMEt vector used for testing enhancer activity. Elements used in this vector are the same as pTME except for a substitution of the mutation cassette with one of CNEs. <b>(C, C’, D, D’, E and E’)</b> Zebrafish embryos injected with pTMEt-CNE2 exhibited transient and specific EGFP expression in the central nervous system at 48 hpf. EGFP expression in embryos from the ET line pTME12 was viewed in lateral (C) and in dorsal (C’) at 48 hpf. Transient EGFP expression in WT embryos injected with pTMEt-CNE2 and embryos were viewed from lateral (D) and dorsal (D’). Embryos injected with pTMEt-CNE2 were prepared for WISH with <i>egfp</i> RNA probes and lateral (E) and dorsal (E’) views of a representative embryo indicate the specific GFP expression in the brain and spinal cord.