Isolation of turkey adrenocortical cell angiotensin II (AII) receptor partial cDNA: evidence for a single-copy gene expressed predominantly in the adrenal gland.

A turkey adrenocortical cell AII receptor cDNA fragment (714 bp) was isolated by RT-PCR using oligonucleotide primers based on rat aortic smooth muscle (RASM) and bovine adrenal type-1 (AT1) receptor cDNA coding sequences as primers. Sequence analysis indicated 73% nucleotide identity and 78% amino acid identity to the RASM AT1 receptor. Notable differences were 1) two additional Cys at positions 92 and 99 (first extracellular loop), 2) deletion of amino acid 168, formation of a triplet Asn sequence (Asn 186, 187, 188) and substitution of Arg192 with Pro (second extracellular loop) and 3) two additional potential protein kinase C phosphorylation sites, Thr221 and Thr233 (third intracellular loop). Southern blot analysis indicated that the receptor is a product of a single-copy gene. Northern blot analysis indicated at least three mRNA transcripts (7.5, 3.5 and 2.0 kb) expressed predominantly in the adrenal gland.