Sodium-dependent serotonin transporter (SLC6A4) (SERT)

The Sodium-dependent serotonin transporter (SLC6A4), commonly known as SERT, is a transmembrane protein that plays a critical role in the central and peripheral nervous systems by regulating the concentration of serotonin (5-HT) in the synaptic cleft (Source: UniProt: P31645). It functions by transporting serotonin from the extracellular space back into the presynaptic neuron, a process driven by the co-transport of sodium and chloride ions. The central binding site, or S1 site, is the primary orthosteric pocket where serotonin binds and where most clinical antidepressants, such as Selective Serotonin Reuptake Inhibitors (SSRIs), exert their effects by competitively inhibiting reuptake (Source: PubMed: 27049939). This site is located within the core of the transporter and is distinct from the allosteric site (S2), which can also modulate transporter activity. Dysregulation of this transporter is a hallmark of various psychiatric conditions, including major depressive disorder, anxiety, and obsessive-compulsive disorder (Source: NCBI Gene: 6532). Beyond the brain, SERT is also expressed in blood platelets and the gastrointestinal tract, where it regulates local serotonin levels and influences gut motility and hemostasis. Pharmacological modulation of the SERT central binding site remains a cornerstone of modern psychopharmacology, though it is associated with side effects like sexual dysfunction and serotonin syndrome (Source: StatPearls: NBK554406).

Other names

5-HTT5-HT transporterSerotonin transporterHTTOCD1SERT1hSERT

Competitive inhibition of serotonin reuptake by binding to the central orthosteric site (S1), thereby increasing extracellular serotonin levels and prolonging its action on post-synaptic receptors (Source: PubMed: 27049939, StatPearls: NBK554406).