The plasma membrane, also known as the cell membrane, is a crucial defining component of all living cells. It serves as a selectively permeable barrier that separates the cell's internal environment from the external environment. The plasma membrane is composed of a lipid bilayer, primarily consisting of phospholipids, cholesterol, and membrane proteins. The phospholipids arrange themselves in a bilayer structure, with the hydrophilic heads facing outward towards the aqueous environments and the hydrophobic tails facing inward, creating a hydrophobic core. This lipid bilayer provides the membrane with its characteristic fluidity and flexibility, allowing it to accommodate numerous cellular processes. Integral membrane proteins are embedded within the lipid bilayer and play vital roles in cell signalling. Receptor proteins are crucial for receiving signals from the extracellular environment and initiating cellular responses. These receptor proteins can be classified into various types, including G protein-coupled receptors (GPCRs), receptor tyrosine kinases (RTKs), and ligand-gated ion channels. GPCRs are a large family of receptors that are involved in numerous signalling pathways. When a ligand binds to a GPCR, it induces a conformational change in the receptor, leading to the activation of intracellular signalling cascades. GPCRs regulate a wide range of physiological processes, such as neurotransmission, hormone signalling, and immune responses. RTKs, on the other hand, are receptors with intrinsic enzymatic activity. Ligand binding to RTKs leads in many cases to receptor dimerization and autophosphorylation, triggering downstream signalling pathways. RTKs are involved in cell growth, differentiation, and survival and dysregulation of RTK signalling is associated with various diseases, including cancer. Ligand-gated ion channels are another type of membrane protein involved in cell signalling. These channels, upon ligand binding, undergo conformational changes that allow the flow of specific ions across the membrane. This ion flux generates electrical signals, which are critical for neuronal communication and muscle contraction. The plasma membrane also contains within it structures termed lipid rafts, specialized microdomains rich in cholesterol and sphingolipids. Lipid rafts are involved in the organization and compartmentalization of membrane proteins, allowing for the formation of signalling complexes. These membrane microdomains play a crucial role in signal transduction by facilitating the assembly of signalling molecules, such as receptors, kinases, and adaptors, into functional complexes. In addition to its role in signal reception, the plasma membrane is also involved in signal transduction. Once a signal is received by a receptor protein, it initiates a series of intracellular events that transmit the signal to the target molecules within the cell. This can involve the activation of cytosolic secondary messengers, such as cyclic adenosine monophosphate (cAMP) and inositol trisphosphate (IP3), which propagate the signal to downstream effectors and modulate cellular responses in the cytoplasm, or to membrane-associated second messengers such as PIP3 and diacylglycerol. Finally, the plasma membrane plays a crucial role in cell adhesion and communication. Cell adhesion molecules, such as integrins, cadherins, and selectins, are integral membrane proteins that mediate both cell-cell and cell-extracellular matrix interactions. These molecules are involved in various cellular processes, including tissue development, immune response, and wound healing. We offer a comprehensive product catalogue of research reagents for studying the plasma membrane, including Glucose Transporter GLUT1 antibodies, STK39 antibodies, CD98 antibodies, Glucose Transporter GLUT1 ELISA Kits, and Aquaporin 4 ELISA Kits. Explore our full plasma membrane product range below and discover more, for less. Alternatively, you can explore our Channels and ATPases product ranges.