Plasma Membrane Markers

The plasma membrane forms a selectively permeable barrier separating intracellular contents from the extracellular environment. The basic structure, fluidity and permeability of the membrane is provided by a phospholipid bilayer. Additional lipid components including cholesterol and sphingolipids further modulate fluidity and membrane domain organisation. Membrane-associated proteins are required for cell signalling, adhesion, motility, cytoskeletal scaffolding, membrane organisation, and cellular homeostasis. Acting as receptors, ion channels, ion pumps, transporters, enzymes, adhesion proteins or signalling molecules, these integral and peripheral proteins constitute useful plasma membrane markers. A critical function of the plasma membrane is to maintain cellular homeostasis. Through its selective permeability, the membrane regulates the movement of ions, nutrients, and waste products into and out of the cell, achieving osmotic equilibrium and a constant electrochemical gradient (membrane potential). While smaller, hydrophobic molecules diffuse freely across the lipid bilayer, the selective movement of ions and osmolytes requires active transport using molecular pumps or passage through protein channels in a facilitated diffusion. Ion pumps such as the sodium-potassium ATPase and PMCA are established plasma membrane markers. The sodium-potassium ATPase maintains the electrochemical gradient pumping sodium ions out of the cell and potassium ions into the cell. PMCA is responsible for pumping calcium ions out of the cell and regulating intracellular calcium levels. Further, the ATPase PMA1 acts as a proton pump removing H⁺ ions from the cell to regulate membrane potential and cytoplasmic pH levels. GLUT1 is a glucose transporter responsible for glucose uptake into cells and energy production. The plasma membrane also plays a crucial role in cell signalling and communication. For example, transmembrane receptor proteins CD98 and CXCR4 recognise and transduce extracellular signals from neighbouring cells, hormones and growth factors. The cholesterol-binding integral protein CAV1 acts as a marker for specialised membrane invaginations called caveolae. These small pits compartmentalise signalling complexes and enable caveolae-mediated endocytosis. The interaction between CAV1 and cholesterol is also important for lipid metabolism and the stabilisation of lipid raft microdomains. Cell-cell adhesion is necessary for the formation and maintenance of tissues. E Cadherin, N Cadherin, and Pan Cadherin mediate calcium-dependent cell adhesion, promoting strong intercellular connections. E Cadherin, in particular, is important for epithelial cell adhesion and tissue integrity, while N Cadherin is involved in neuronal development and synapse formation. Together these transmembrane anchors are essential for embryonic development, tissue morphogenesis, wound healing, and maintenance of tissue architecture. The plasma membrane is essential for maintaining cellular homeostasis, enabling cell-cell signalling, facilitating cell-cell adhesion, and organising the membrane. We offer a range of plasma membrane marker antibodies, including Calreticulin antibodies, CD27 antibodies, CD40 antibodies, CD98 antibodies, and Sodium Potassium ATPase antibodies, to study these processes. Our plasma membrane marker antibodies have been validated across multiple applications, including western blotting (WB), flow cytometry, immunocytochemistry (ICC), and immunohistochemistry (IHC), and cover various host species, clonalities, isotypes and conjugates.