<p>The tumour necrosis factor (TNF) receptor (TNFR) superfamily comprises more than 20 type-I transmembrane proteins. Family members are defined based on similarity in their extracellular domain - a region that contains many cysteine residues arranged in a specific repetitive pattern [<cite idref="PUB00046030"/>]. The cysteines allow formation of an extended rod-like structure, responsible for ligand binding [<cite idref="PUB00000892"/>]. </p> <p>Upon receptor activation, different intracellular signalling complexes are assembled for different members of the TNFR superfamily, depending on their intracellular domains and sequences [<cite idref="PUB00046031"/>]. Activation of TNFRs can therefore induce a range of disparate effects, including cell proliferation, differentiation, survival, or apoptotic cell death, depending upon the receptor involved [<cite idref="PUB00046032"/>, <cite idref="PUB00046033"/>]. </p> <p>TNFRs are widely distributed and play important roles in many crucial biological processes, such as lymphoid and neuronal development, innate and adaptive immunity, and maintenance of cellular homeostasis [<cite idref="PUB00046031"/>]. Drugs that manipulate their signalling have potential roles in the prevention and treatment of many diseases, such as viral infections, coronary heart disease, transplant rejection, and immune disease [<cite idref="PUB00046034"/>]. </p> <p>This entry represents tumour necrosis factor receptor superfamily member 3 (TNF receptor 3; also known as lymphotoxin-beta receptor). TNF receptor 3 acts as a receptor for the heterotrimer of lymphotoxin-alpha and beta, and also for the TNF ligand LIGHT. Activation of the receptor promotes apoptosis via recruitment of TNFR-associated factor 3 (TRAF3) [<cite idref="PUB00046065"/>]. </p><p/> Tumour necrosis factor receptor 3