Figure 3

AKAP7 Gene Evolution. AKAP7 ESTs from chordate (Ciona Intestinalis), basal vertebrate (lamprey), teleost (zebrafish), and mammals (Opossum, Dog, Rat, and Human) were aligned to their respective genomes to determine exon positions and orientation. Coding sequence for the AKAP7 RI/RII binding domain is found in the 3’ terminal exon of AKAP7 splice variants and is identified in the AKAP7 genes from lamprey to humans. The AKAP7α 5’ exon first appears in zebrafish and an ortholog of this exon is identified in the genes of multiple mammals. The AKAP7β-specific exon first appears in the dog AKAP7 gene and is conserved in mammalian genes. An AKAP7 long form splice variant is found in each species, though AKAP7γ orthologs are only identified in species following the divergence of dog. The AKAP7γ 5’ exon is lost in rats, and is concomitant with the incorporation of the AKAP7δ 5’ exon (AKAP7δ exon is identified in the cow AKAP7 gene but no ESTs were detected).