Neuronal ganglioside

Neuronal gangliosides are sialic acid-containing glycosphingolipids that are highly enriched in the outer leaflet of neuronal membranes, particularly at the presynaptic terminals of cholinergic neurons (Schengrund, 2015). They function as essential components of the dual-receptor mechanism for clostridial neurotoxins, such as Botulinum neurotoxin (BoNT) and Tetanus neurotoxin (TeNT) (Rummel, 2016). In this mechanism, the toxin's heavy chain first binds to gangliosides like GT1b or GD1a, which anchors the toxin to the membrane and facilitates its subsequent binding to high-affinity protein receptors like Synaptotagmin or SV2 (Dong et al., 2003). This interaction is a prerequisite for the endocytosis of the toxin and the subsequent cleavage of SNARE proteins, which inhibits acetylcholine release and leads to flaccid paralysis (Pirazzini et al., 2017). Beyond their role as toxin receptors, gangliosides are involved in modulating ion channels, cell signaling, and maintaining the stability of lipid rafts (Willison & Yuki, 2002). They are also clinically significant as targets for autoantibodies in autoimmune peripheral neuropathies, such as Guillain-Barré and Miller Fisher syndromes (Yuki & Hartung, 2012).

Other names

GangliosideSialic acid-containing glycosphingolipidGT1bGD1aGM1GD1bGQ1b

Neuronal gangliosides serve as the initial binding site for clostridial neurotoxins (dual-receptor model), where they concentrate the toxin on the presynaptic membrane to facilitate binding to high-affinity protein receptors (e.g., SV2 or synaptotagmin) for internalization (Rummel, 2016).