Abstract |
Angiotensin II (Ang-II) receptors were solubilized from differentiated N1E-115 neuroblastoma cell membranes with the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1- propanesulfonate ( CHAPS), whereas other detergents, such as digitonin, sodium cholate, and Triton X-100, were much less effective. Binding of 125I-Ang-II or the antagonist 125I-Sar1,Ile8-Ang-II to 1% CHAPS-solubilized membranes was saturable and of high affinity. Moreover, these solubilized receptors retained the pharmacological specificity characteristic of particulate receptors. Covalent cross-linking of 125I-Ang-II to either particulate or solubilized membrane fractions, with the homobifunctional cross-linker disuccinimidyl suberate, followed by size exclusion chromatography or sodium dodecyl sulfate- polyacrylamide gel electrophoresis analysis, resulted in the identification of the same two distinct 125I-Ang-II binding entities, with approximate molecular masses of 111 kDa and 68 kDa. The estimated molecular weights of the Ang-II binding sites in differentiated N1E-115 cells are in good agreement with the molecular weights obtained previously from solubilized rat brain membranes, suggesting that the N1E-115 Ang-II receptors are similar to those present in the brain. Finally, solubilized N1E-115 membranes could be purified by Ang-II affinity chromatography, resulting in only a single protein (66 kDa), which retained its ability to specifically bind 125I-Ang-II.
|
Authors | I R Siemens, H J Adler, K Addya, S J Mah, S J Fluharty |
Journal | Molecular pharmacology
(Mol Pharmacol)
Vol. 40
Issue 5
Pg. 717-26
(Nov 1991)
ISSN: 0026-895X [Print] United States |
PMID | 1944241
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
|
Chemical References |
- Membrane Proteins
- Receptors, Angiotensin
- Angiotensin II
|
Topics |
- Angiotensin II
(metabolism)
- Animals
- Binding Sites
- Binding, Competitive
- Chromatography, Affinity
- Chromatography, Gel
- Electrophoresis, Polyacrylamide Gel
- Membrane Proteins
(isolation & purification)
- Mice
- Neuroblastoma
(chemistry)
- Receptors, Angiotensin
(isolation & purification)
- Solubility
- Tumor Cells, Cultured
|