Structure of the 5′ end of the human ankyrin-1 erythroid cDNA.

(A) A diagram of the 5′ end of the human ankyrin-1 cDNA is shown. The composite ankyrin cDNA is denoted by the line and the location of the initiation codon is shown (top). The genomic organization of the 5′end of the ankyrin-1 gene is shown, with the exons denoted by the boxes. Sequences obtained by 5′ RACE are denoted by the hatched box. Oligonucleotide primers used in 5′ RACE experiments are denoted by the arrows. The location of the probe used in genomic library screening, ANK58, is shown (bottom). (B) The 5′ end of the human ankyrin-1 chromosomal gene. A genomic DNA clone, λAN 261, spanning approximately 16-kb of DNA, was isolated from a human genomic DNA library. An EcoRI restriction map of clone λAN 261 is shown (top). This clone contained exon 1 of the ankrin-1 erythroid gene in a 2-kb EcoRI fragment (middle). The core ankyrin-1 promoter had very high G+C content and contained restriction enzyme sites found in HTF islands (bottom). See text for details.