Sequence and structural features of the 5′-flanking region of the PECAM-1 gene. The 1,588-bp sequence shown contains 1,252 bases of the 5′-flanking region of the PECAM-1 gene, as well as the 5′ untranslated region, exon 1 and the beginning of intron 1. All numbering is relative to the Transcription Initiation Site (arrow at +1). The translated protein sequence corresponding to exon 1 is shown as single letter amino acids. Putative regulatory elements are boxed and labeled, and selected restriction enzymes sites used in subcloning this fragment, either in part or in its entirety, are also shown. GATA elements potentially involved in transcriptional regulation of the PECAM-1 promoter are shown in white against a blue background. An Alu sequence spanning nucleotides −859 to −557 is backshadowed in yellow, and contains one of three putative SSREs (shown in red). The ATG translation start site at +205 is shown in bold.