Dopamine 5 receptor mediates Ang II type 1 receptor degradation via a ubiquitin-proteasome pathway in mice and human cells
J. Clin. Invest. 118:6 doi:10.1172/JCI33637 [Go to this article.]

Figure 4
Characterization of AT₁R degradation by [³⁵S] metabolic labeling.

AT₁R/D₅R HEK293 cells were treated with vehicle, Ang II (100 nM for 30 min), or Fen (1 μM for 2 h), pulsed with [³⁵S] Met/Cys, and then chased with cold amino acids for the indicated times. The cell lysates were immunoprecipitated with anti-GFP antibody, and the immunocomplexes were subjected to SDS-PAGE. Dried gels were exposed to X-ray films. (A) Autoradiographs of AT₁R degradation with vehicle, Ang II, and Fen treatment. (B) Quantification of AT₁R degradation. Values are mean ± SEM of arbitrary density units normalized to the time-0 value (n = 3). The decrease in AT₁R protein in the presence of vehicle followed a first-order exponential curve, with a half-life of 127.6 min. The decrease in AT₁R protein with Ang II or Fen treatment also followed a first-order exponential curve; treatment with Ang II decreased the half-life of AT₁R protein to 16.8 min, while treatment with Fen resulted in a half-life of 37.7 min. P < 0.05, Fen versus vehicle and versus Ang II, repeated-measures ANOVA. No error bar is visible when the SEM is smaller than the symbol.