Endothelial regulation of calmodulin expression and eNOS-calmodulin interaction in vascular smooth muscle.

Calmodulin (CaM) is a Ca sensor protein that is required for numerous vascular smooth muscle cell (VSMC) functions. Since CaM is not expressed enough for its many target proteins, factors that modulate its expression and interactions with targets in VSMCs can have extensive effects on vascular functions. VSMCs receive many regulatory inputs from endothelial cells (ECs).

Novel regulations of the angiotensin II receptor type 1 by calmodulin.

The angiotensin II receptor type 1 (ATR) mediates many Ca-dependent actions of angiotensin II (AngII). Calmodulin (CaM) is a key transducer of Ca signals in cells. Two locations on the receptor's submembrane domains (SMD) 3 and 4 are known to interact with CaM.

Suppression of store-operated Ca entry by activation of GPER: contribution to a clamping effect on endothelial Ca signaling.

The G protein-coupled estrogen receptor 1 (GPER, formerly also known as GPR30) modulates many Ca-dependent activities in endothelial cells. However, the underlying mechanisms are poorly understood. We recently reported that GPER acts to prolong cytoplasmic Ca signals by interacting with and promoting inhibitory phosphorylation of the plasma membrane Ca-ATPase.

Estrogen Enhances Linkage in the Vascular Endothelial Calmodulin Network via a Feedforward Mechanism at the G Protein-coupled Estrogen Receptor 1.

Estrogen exerts many effects on the vascular endothelium. Calmodulin (CaM) is the transducer of Ca(2+) signals and is a limiting factor in cardiovascular tissues. It is unknown whether and how estrogen modifies endothelial functions via the network of CaM-dependent proteins.

Hetero-oligomeric Complex between the G Protein-coupled Estrogen Receptor 1 and the Plasma Membrane Ca2+-ATPase 4b.

The new G protein-coupled estrogen receptor 1 (GPER/GPR30) plays important roles in many organ systems. The plasma membrane Ca(2+)-ATPase (PMCA) is essential for removal of cytoplasmic Ca(2+) and for shaping the time courses of Ca(2+)-dependent activities. Here, we show that PMCA and GPER/GPR30 physically interact and functionally influence each other.

Biosensor-based approach identifies four distinct calmodulin-binding domains in the G protein-coupled estrogen receptor 1.

The G protein-coupled estrogen receptor 1 (GPER) has been demonstrated to participate in many cellular functions, but its regulatory inputs are not clearly understood. Here we describe a new approach that identifies GPER as a calmodulin-binding protein, locates interaction sites, and characterizes their binding properties. GPER coimmunoprecipitates with calmodulin in primary vascular smooth muscle cells under resting conditions, which is enhanced upon acute treatment with either specific ligands or a Ca(2+)-elevating agent.