NOVEL SUBTYPE OF HUMAN ANGIOTENSIN-II TYPE-1 RECEPTOR - CDNA CLONING AND EXPRESSION

Angiotensin II (All) plays a major role in regulation of cardiovascular function and fluid homeostasis through the action of an AII type 1 receptor (AT(1)R). The cDNA encoding a novel subtype of human AT(1)R (AT(1b)R) was cloned from a human placental cDNA library. The full-length cDNA clone (1563 bp) encoded a polypeptide that consists of 359 amino acid (aa) residues with 97.2% aa identity to the human AT(1a)R. All the aa replacements between two human AT(1)Rs reside within the C-terminal half region of AT(1)R molecule. The 2.4-knt AT(1)b(R) mRNA is expressed in the lung, placenta and Liver, and differs from AT(1a)R mRNA in its tissue distribution. The AT(1b)R expressed in COS-7 cells is pharmacologically distinct from the human AT(1a)R. (C) 1994 Academic Press, Inc.