Surface receptor

The term "Surface receptor" refers to a broad and diverse class of proteins embedded in the plasma membrane of cells that facilitate communication between the cell and its external environment. These receptors are categorized into several major families, including G protein-coupled receptors (GPCRs), receptor tyrosine kinases (RTKs), and ligand-gated ion channels. Their primary biological function involves binding to specific extracellular signaling molecules, known as ligands, to trigger a physiological response within the cell, such as changes in gene expression or metabolic activity. Surface receptors are of paramount importance in pharmacology, as their extracellular location makes them highly accessible to therapeutic agents; they are the targets for more than 50% of currently marketed drugs. Dysregulation, mutation, or over-expression of these receptors is a hallmark of many diseases, including various cancers, where growth factor receptors may be constitutively active, and neurological disorders, where neurotransmitter receptors may be imbalanced. Because this term represents a functional category of thousands of distinct proteins rather than a single molecular entity, it is considered too generic for specific therapeutic target identification.

Other names

Cell surface receptorTransmembrane receptorMembrane-bound receptorPlasma membrane receptor

Surface receptors function by binding extracellular ligands (such as hormones, neurotransmitters, or cytokines), which induces a conformational change or clustering that activates intracellular signaling pathways or allows the passage of ions.