Suppression of MR transcriptional activity by Vpr in African green monkey kidney (CV-1) cells.

(A) CV-1 cells, lacking MR, were transfected with Vpr- and MR-expressing plasmids. MR-mediated transcription activity, monitored by the MR-responsive MMTV-luciferase reporter, exhibited a sigmoidal dose-response to aldosterone and across the aldosterone concentration range, which was inhibited by Vpr. (B) Vpr markedly suppressed MR transcriptional activity in CV-1 cells transfected with MR and cultured with aldosterone (100 nM). (C) Both sVpr and MR antagonist spironolactone (1 μM) suppressed aldosterone-induced (100 nM) MR transcription activity; the spironolactone-mediated suppression was not further reduced by sVpr. n = 3–6. n.s., not significant; *P P < 0.001, ANOVA, Bonferroni correction.