Leucine-rich repeat, immunoglobulin-like and transmembrane domains 1 (LRIT1)

LRIT1 (Leucine-rich repeat, immunoglobulin-like and transmembrane domains 1) is a transmembrane synaptic adhesion-like protein specifically enriched at retinal cone photoreceptor synapses. It contains leucine-rich repeat motifs, immunoglobulin-like domains, fibronectin type III domains, and a transmembrane region anchoring it at the synapse. LRIT1 is critical for normal cone synaptic communication, enabling dynamic scaling of photoreceptor response to varying light conditions and maintaining visual acuity. LRIT1 forms a molecular complex with the glutamate receptor mGluR6 on ON-bipolar cells and the photoreceptor scaffold protein Frmpd2, regulating synaptic architecture and functional connectivity. Knockout or deficiency of LRIT1 in mice leads to abnormal synaptic signaling and impaired adaptation in vision, indicating its essential role in retinal function, but it is not a direct therapeutic drug target.

Other names

LRRC21FIGLER9Photoreceptor-associated LRR superfamily proteinRetina-specific protein PALfibronectin type III, immunoglobulin and leucine rich repeat domains 9PALDKFZP434K091

None known (no current drugs or agents act mechanistically through LRIT1)