Fig. 1. Sequence and functional conservation between Math1 and Cath enhancers. (A) The percent sequence conservation between the Math1 enhancer (Accession Number, AF218258) and sequences in human (HATH1, Accession Number, AF18259) and chicken (Cath1, Accession Number, AF467292). These sequences are found 3' to the coding sequences, 3 kb for Math1, 3.4 kb for HATH1 and 1.7 kb for Cath1. (B) Sequence from 1192 to 1260 comparing mouse, human and chick sequences across the region containing the essential E-box and the Zic1-binding site in the Math1 enhancer. Details of the mutations in the constructs shown in Fig. 5 are shown. (C) The Math1 enhancer (Math1/lacZ Tg) and (D) the Cath1 enhancer (Cath1/lacZ Tg) have the same activity in E10.5 transgenic embryos as shown with whole-mount X-gal stained embryos. (E) Cross-section of the neural tube of a Math1/lacZ transgenic mouse embryo showing the dorsal pattern of expression for comparison with F, which is the expression of the same transgene after electroporation into one side of a chick neural tube (arrow). Note the DNA enters cells along the DV axis but expression of the transgene is restricted dorsally.