Fig. 3. Sequence alignment of a region conserved between the chick, mouse, human and horn shark Hoxa3 5' flanking regions. The kreisler-binding site KrA previously identified in the mouse enhancer (Manzanares et al., 1999a) is boxed, as are the putative bipartite HOX/PBC sites A and B, and the Prep/Meis consensus motif. The unbroken black lines above the sequence indicate the double-stranded oligonucleotides A3-PP2, A3-PH1 and A3-PHP1 used in binding and competition assays (Fig. 6). Dashes represent an identity and dots a missing nucleotide.