Invertebrate glycine receptor (GlyR) (GlyR)

Invertebrate glycine receptors (GlyRs) are members of the Cys-loop superfamily of ligand-gated ion channels that mediate fast inhibitory neurotransmission in various non-vertebrate species, including nematodes, insects, and mollusks (Jones & Sattelle, 2008). These receptors function as chloride-selective channels that, upon binding glycine, induce membrane hyperpolarization, thereby reducing neuronal excitability and muscle contraction (McCracken et al., 2010). While they share structural homology with vertebrate GlyRs, invertebrate versions often exhibit distinct pharmacological sensitivities; for instance, some are less sensitive to the classical antagonist strychnine but are highly sensitive to macrocyclic lactones like ivermectin (Lynagh & Lynch, 2012). In organisms like Caenorhabditis elegans, these receptors are encoded by genes such as glc-1, glc-2, and glc-3, and they play vital roles in regulating locomotion and pharyngeal pumping. Because of their essential role in parasite physiology and their divergence from human receptor subtypes, they serve as critical targets for anthelmintic and insecticidal drugs used in human medicine, veterinary care, and agriculture.

Other names

Invertebrate glycine-gated chloride channelGlycine-activated chloride channelGLC-1GLC-2GLC-3GLC-4Cys-loop ligand-gated ion channel

Agonism or positive allosteric modulation of the chloride channel, leading to an influx of chloride ions, hyperpolarization of the postsynaptic membrane, and subsequent inhibition of neuromuscular activity.