Cellular lipid membranes mediating Ca²⁺ transport

Cellular lipid membranes mediating Ca²⁺ transport refer to the phospholipid bilayers of the plasma membrane and intracellular organelles, such as the endoplasmic reticulum (ER) and mitochondria, which serve as the primary barriers and regulatory interfaces for calcium signaling [1]. These membranes maintain a significant concentration gradient between the cytosol (~100 nM) and the extracellular space or ER lumen (~1 mM), a gradient essential for rapid signal transduction in processes like muscle contraction and neurotransmission [2]. While the lipid bilayer is inherently impermeable to ions, it facilitates Ca²⁺ transport through embedded proteins like voltage-gated calcium channels, the Sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA), and the sodium-calcium exchanger (NCX) [3]. Pharmacological agents that target this system directly include ionophores, such as ionomycin and calcimycin (A23187), which act by forming lipid-soluble complexes with Ca²⁺ to shuttle them across the membrane, bypassing protein-mediated regulation [4]. Because this term describes a complex biological structure and a set of physiological processes rather than a single molecular entity, it is generally considered a biological system or site of action rather than a discrete therapeutic target in drug discovery [5, 6].

Other names

Cellular lipid bilayerBiological membranesCalcium-transporting membranesPlasma membrane calcium transport system

Ionophore-mediated transport of divalent cations across lipid bilayers