PT  - JOURNAL ARTICLE
AU  - Jian-Hua Zhang
AU  - Jeffery W. Stobb
AU  - Jodie M. Hanesworth
AU  - Michael F. Sardinia
AU  - Joseph W. Harding
TI  - Characterization and Purification of the Bovine Adrenal Angiotensin IV Receptor (AT<sub>4</sub>) Using [<sup>125</sup>I]Benzoylphenylalanine-Angiotensin IV as a Specific Photolabel
DP  - 1998 Oct 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 416--424
VI  - 287
IP  - 1
4099  - http://jpet.aspetjournals.org/content/287/1/416.short
4100  - http://jpet.aspetjournals.org/content/287/1/416.full
SO  - J Pharmacol Exp Ther1998 Oct 01; 287
AB  - The Ang IV receptor, AT4, has been shown to play important roles in various mammalian tissues. In this study, structural properties of the AT4 receptor from bovine adrenals are described using a novel photoactive analog of Ang IV, [125I]Benzoylphenylalanine-Ang IV (BP-Ang IV), recently developed in our laboratory. [125I]BP-Ang IV is identical to Ang IV with regards to binding specificity and affinity and is easily cross-linked to the AT4 receptor under UV light, thus greatly facilitating the structural analysis of the AT4 receptor by SDS-PAGE. Comparisons between the native, reduced and nonreduced forms of the AT4 receptors by SDS-PAGE revealed that this receptor consists of multiple subunits. The subunit containing the Ang IV binding site (designated as thealpha subunit) has a molecular weight of ∼165 kDa and contained ∼20% N-linked carbohydrates. A subunit similar to the adrenal alpha subunit of the AT4 receptor was identified in all of the bovine tissues examined. Hippocampus and aorta contained additional [125I]BP-Ang IV bound protein bands with molecular weights of 150 and 125 kDa, respectively. Further, the alpha subunit was purified to homogeneity using a method that integrates electrofractionation with conventional protein purification techniques. The American Society for Pharmacology and Experimental Therapeutics