The integrin-cortex complex under control of GPCRs

This editorial refers to ‘Coordination of fibronectin adhesion with contraction and relaxation in microvascular smooth muscle’ by Z. Hong et al ., doi:10.1093/cvr/cvs239. Few topics in cardiovascular physiology have attracted as much attention as the mechanisms for autoregulatory contraction of arterioles and their control over the blood flow. Whether mechanotransduction via myogenic, flow-dependent shear stress, neurogenic, or metabolic controls, the discussion has been focused on the contractile machinery within vascular smooth muscle cells.In recent years, however, evidence has come to light suggesting that within a smooth muscle cell non-contractile cytoplasmic regions underneath the plasma membrane may also be part of the control over mechanotransduction. These cortical regions are accessible with nanoscale tools, such as the tips of an atomic force microscope (AFM). Analysis with such tools has shown that the myogenic contraction requires an integrated extracellular matrix–adhesion–cytoskeletal signalling complex that depends on integrins for both outside-in and inside-out signalling.1 Mechanical stress applied via integrins serves as an important sensory mechanism for vascular functions, including contractile and relaxation processes, proliferation, migration, attachment, and cell phenotype determination.2 Smooth …