Identification of a cAMP-response Element in the Regulator of G-protein Signaling-2 (RGS2) Promoter as a Key Cis-regulatory Element for RGS2 Transcriptional Regulation by Angiotensin II in Cultured Vascular Smooth Muscles

Abstract

Background: Angiotensin II-induced regulator of G-protein signaling-2 (RGS2) expression is an important negative feedback loop in blood pressure homeostasis. Results: A conserved cAMP-response element-binding protein (CREB) binding site is found in the RGS2 promoter and is associated with three SNPs identified in hypertensive patients. Conclusion: CREB links the angiotensin II/PKC/iPLA 2 ␤/PKA signaling and RGS2 transcription. Significance: This study delineates a negative feedback loop with potential importance in the pathogenesis of human hypertension.

Smooth-muscle BMAL1 participates in blood pressure circadian rhythm regulation

“…BMAL1 adenoviral expression in VSMC was verified by Western blot (Z. Guo and M. Gong, data not shown). Rock2 promoter activity was assayed by a modified dual luciferase enzyme assay as described (55). correlation of ROCK2 function (pMYPT1 853 phosphorylation) with vasoconstriction ( Figure 6, B and C, vs. Figure 2) and MLC 20 phosphorylation ( Figure 6, B and C, vs. Figure 4) was observed in WT mice, but lost in SM-Bmal1-KO mice.…”

“…Bmal1-deficient and WT VSMCs were isolated from SM-Bmal1-KO and WT littermate aortas as described (49,54,55). Cells were cotransfected with pGl3-Rock2 luciferase vector and a Renilla luciferase using Lipofectamine-Plus Reagent (Life Technologies).…”

Smooth Muscle-specific Expression of Calcium-independent Phospholipase A2β (iPLA2β) Participates in the Initiation and Early Progression of Vascular Inflammation and Neointima Formation

“…Real Time PCR-Primer sequences used for quantification of mRNA levels from mouse carotid arteries by real time PCR are listed in supplemental Table 1 except for 18 S rRNA that has been described previously (16,20,24,29,33). The procedures of real time PCR were described previously (16,20,24,29,33).…”

“…When they achieved 70 -80% confluence, cells were co-transfected with an iPLA 2 ␤-Luc reporter and pRL-TK vector (Promega) using Lipofectamine-Plus reagent. iPLA 2 ␤ promoter activity was analyzed as described previously (24).…”

“…Moreover, smooth muscle iPLA 2 ␤ has been functionally implicated in Ca 2ϩ influx (18), proliferation (17,23), transcriptional regulation (16,24), Ca 2ϩ sensitization of smooth muscle contraction (19), and diabetes-associated vascular hypercontractility (20).…”