Leucine-rich repeat transmembrane neuronal protein 4 (LRRTM4)

Leucine-rich repeat transmembrane neuronal protein 4 (LRRTM4) is a synaptic adhesion protein mainly localized at the postsynaptic membrane of excitatory synapses, especially in the central nervous system and retina[1][2][4][5]. It is a member of the LRRTM family, which features a leucine-rich repeat-containing extracellular N-terminal domain, a single transmembrane helix, and a cytoplasmic domain. LRRTM4 is specifically enriched at rod bipolar cell dendritic tips in the retina, where it regulates synaptic assembly, structure, and signaling—primarily through interactions with heparan sulfate proteoglycans such as pikachurin and glypicans, and possibly with presynaptic neurexins[1][2][5][7]. LRRTM4 plays a crucial role in excitatory synapse development, and its dysfunction has been linked to neurological and visual disorders, including autism spectrum disorder, epilepsy, and macular degeneration[1][4][5]. It acts to organize complex transsynaptic protein networks that are vital for synaptic specificity and signaling fidelity, especially at specialized ribbon synapses in the retina[1][2][5]. No direct drug interactions or mechanisms of action for therapeutic agents are currently known for LRRTM4.

Other names

Leucine-rich repeat transmembrane neuronal 4UNQ3075/PRO9907FLJ12568LRRTM4