Leucine-rich repeat-containing protein 4C (LRRC4C)

**Leucine-rich repeat-containing protein 4C (LRRC4C)**, also known as **Netrin-G ligand-1 (NGL-1, NGL1)**, is a type I transmembrane protein highly expressed in the brain, particularly at the postsynaptic membrane of excitatory synapses[1][2]. It is a cell adhesion molecule that interacts trans-synaptically with presynaptic netrin-G1, promoting the formation, maturation, and plasticity of excitatory synapses, especially in the hippocampus and cortex[2][3][1]. LRRC4C contains distinct leucine-rich repeat domains, an immunoglobulin C2 domain, and a PDZ domain-binding motif, enabling interaction with postsynaptic density proteins such as PSD-95, which links synaptic membrane adhesion to downstream signaling and postsynaptic receptor clustering[2][3][1]. LRRC4C is critical for normal hippocampal excitatory synapse development, synaptic transmission, axon differentiation, and memory function. Its deletion or dysfunction has been linked to neurodevelopmental disorders (notably autism), synaptic structural and functional deficits, and acts as a suppressor in certain brain tumors, notably glioblastoma[1][2]. Altered LRRC4C function may disrupt synaptic signaling, increase susceptibility to neurological disease, or contribute to tumorigenesis[1]. There is currently no evidence of approved therapeutic drugs specifically targeting LRRC4C, and no clinical biomarkers or established mechanisms of drug action identified for this molecule[3][4].

Other names

NGL-1NGL1KIAA1580Netrin-G ligand-1Netrin-G1 ligandUNQ292/PRO331