Tissue specific role of calcium sensing receptor

Abstract

IT Centre of Excellence for Advanced Education and Research,P14, Rajiv Gandhi Infotech Park, Phase 1, Hinjewadi, Pune, Maharashtra­411057, India.E­mail: sudhirk@isquareit.ac.in; Contact number: +91­20­22933441 December 2013 Key words: CaSR, G protein­coupled receptor, signalingAbstractThe calcium sensing receptor (CaSR) is a member of the largest family of cell surface receptors, the Gprotein­coupled receptors involved in calcium homeostasis. Studies identified a crucial role for the CaSRin systemic calcium homeostasis through its ability to sense small changes in circulating calciumconcentration and to combine this information to intracellular signaling pathways that influenceparathyroid hormone secretion. The CaSR is the target of small molecule allosteric modifiers, eitheractivators, calcimimetics, or inhibitors, calcilytics. The presence of CaSR protein in tissues is not directlyinvolved in regulating mineral ion homeostasis points to a role for the CaSR in other cellular functionsincluding the control of cellular proliferation, differentiation and apoptosis. This review will provide acomprehensive exploration of the different aspects of tissue expression patterns, and will relate theirimpact on the functionality of the CaSR from a molecular perspective.Calcium sensing receptorThecalcium­sensingreceptor (CaSR) isaG protein­coupled receptor (GPCR) in the plasma membrane.The CaSR gene is located from base pair 121,902,529 to base pair 122,005,349 on long q arm ofchromosome 3. It plays an essential role in calcium ion homeostasis, cellular proliferation, differentiationand apoptosis (Diez­Fraile et al., 2013). The CaSR is composed of three main regions: a largeextracellular domain, where the interaction with the Ca