Abstract
Genes encoding 3 distinct subtypes of human α2-adrenergic receptor are known and are found, respectively, on chromosome 10, 4, and 2 (α2-C10, α2-C4, and α2-C2 adrenergic receptors). All 3 receptors inhibit adenylyl cyclase via G(i) proteins. To study and compare their regulatory properties we assessed the ability of each to undergo agonist-promoted desensitization and phosphorylation. When Chinese hamster ovary cells stably expressing each of the three receptor genes were incubated with epinephrine for 20 min, a marked decrease in sensitivity to subsequent agonist-mediated inhibition of adenylyl cyclase was observed for the α2-C10 and α2-C2 receptors but not for the α2-C4 receptors. When similar incubations were performed with 32P(i)-labeled cells and the receptors were immunoprecipitated with specific antibodies, α2-C10 and α2-C2 receptors were found to undergo an ~3-fold increase in receptor phosphorylation after epinephrine exposure. When transfected into COS cells epinephrine also stimulated phosphorylation of α2-C10 and α2-C2 receptors while having only a slight effect on α2- C4 receptors. Cotransfection of the cells with the cDNA encoding the β- adrenergic receptor kinase further increased receptor phosphorylation for α2-C10 and α2-C2 receptors while having little or no effect on α2-C4 receptors. Moreover purified and reconstituted recombinant α2-C10 receptors could be phosphorylated in an agonist-dependent fashion whereas α2-C4 receptors could not. These observations suggest receptor subtype-specific differences in susceptibility to regulatory phosphorylation and desensitization.
| Original language | English |
|---|---|
| Pages (from-to) | 10093-10099 |
| Number of pages | 7 |
| Journal | Journal of Biological Chemistry |
| Volume | 269 |
| Issue number | 13 |
| Publication status | Published - Apr 1 1994 |
| Externally published | Yes |
Fingerprint
All Science Journal Classification (ASJC) codes
- Biochemistry
Cite this
Differential desensitization and phosphorylation of three cloned and transfected α2-adrenergic receptor subtypes. / Kurose, Hitoshi; Lefkowitz, Robert J.
In: Journal of Biological Chemistry, Vol. 269, No. 13, 01.04.1994, p. 10093-10099.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Differential desensitization and phosphorylation of three cloned and transfected α2-adrenergic receptor subtypes
AU - Kurose, Hitoshi
AU - Lefkowitz, Robert J.
PY - 1994/4/1
Y1 - 1994/4/1
N2 - Genes encoding 3 distinct subtypes of human α2-adrenergic receptor are known and are found, respectively, on chromosome 10, 4, and 2 (α2-C10, α2-C4, and α2-C2 adrenergic receptors). All 3 receptors inhibit adenylyl cyclase via G(i) proteins. To study and compare their regulatory properties we assessed the ability of each to undergo agonist-promoted desensitization and phosphorylation. When Chinese hamster ovary cells stably expressing each of the three receptor genes were incubated with epinephrine for 20 min, a marked decrease in sensitivity to subsequent agonist-mediated inhibition of adenylyl cyclase was observed for the α2-C10 and α2-C2 receptors but not for the α2-C4 receptors. When similar incubations were performed with 32P(i)-labeled cells and the receptors were immunoprecipitated with specific antibodies, α2-C10 and α2-C2 receptors were found to undergo an ~3-fold increase in receptor phosphorylation after epinephrine exposure. When transfected into COS cells epinephrine also stimulated phosphorylation of α2-C10 and α2-C2 receptors while having only a slight effect on α2- C4 receptors. Cotransfection of the cells with the cDNA encoding the β- adrenergic receptor kinase further increased receptor phosphorylation for α2-C10 and α2-C2 receptors while having little or no effect on α2-C4 receptors. Moreover purified and reconstituted recombinant α2-C10 receptors could be phosphorylated in an agonist-dependent fashion whereas α2-C4 receptors could not. These observations suggest receptor subtype-specific differences in susceptibility to regulatory phosphorylation and desensitization.
AB - Genes encoding 3 distinct subtypes of human α2-adrenergic receptor are known and are found, respectively, on chromosome 10, 4, and 2 (α2-C10, α2-C4, and α2-C2 adrenergic receptors). All 3 receptors inhibit adenylyl cyclase via G(i) proteins. To study and compare their regulatory properties we assessed the ability of each to undergo agonist-promoted desensitization and phosphorylation. When Chinese hamster ovary cells stably expressing each of the three receptor genes were incubated with epinephrine for 20 min, a marked decrease in sensitivity to subsequent agonist-mediated inhibition of adenylyl cyclase was observed for the α2-C10 and α2-C2 receptors but not for the α2-C4 receptors. When similar incubations were performed with 32P(i)-labeled cells and the receptors were immunoprecipitated with specific antibodies, α2-C10 and α2-C2 receptors were found to undergo an ~3-fold increase in receptor phosphorylation after epinephrine exposure. When transfected into COS cells epinephrine also stimulated phosphorylation of α2-C10 and α2-C2 receptors while having only a slight effect on α2- C4 receptors. Cotransfection of the cells with the cDNA encoding the β- adrenergic receptor kinase further increased receptor phosphorylation for α2-C10 and α2-C2 receptors while having little or no effect on α2-C4 receptors. Moreover purified and reconstituted recombinant α2-C10 receptors could be phosphorylated in an agonist-dependent fashion whereas α2-C4 receptors could not. These observations suggest receptor subtype-specific differences in susceptibility to regulatory phosphorylation and desensitization.
UR - http://www.scopus.com/inward/record.url?scp=0028365270&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028365270&partnerID=8YFLogxK
M3 - Article
C2 - 7908287
AN - SCOPUS:0028365270
VL - 269
SP - 10093
EP - 10099
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 13
ER -