Multiple sequence alignment of the C-terminal PDE10A GAF domains to GAF domains of other proteins. Numbers in parentheses at the end of the sequences indicate the amino acid numbers shown for each protein. Numbers in parentheses within sequence alignment indicate the number of amino acids omitted from the alignment for clarity. Arrows mark the motif described as supporting cGMP binding in PDE5. Shading reflects at least 50% conservation. BTPDE2, Bos taurus PDE2 (accession no. M73512); HSPDE5, Homo sapiens PDE5 (AF043731); CFPDE6A, Canis familiaris PDE6 alpha (Y13282); EcfhlA, E. coli FhlA (X52227); CEPDE, C. elegans gene R0807.6 “similar to phosphodiesterase” (Z12017); YEykl0, Saccharomyces cerevisiae ORF YKL069W (Z28069.1); AtphyE, Arabidopsis thaliana phytochrome E (X76610); AFHisK, Archaeoglobus fulgidus gene AF1483 “putative histidine kinase” (AE001000).