Human Leucine-Rich Repeat-Containing Protein 4B (LRRC4B) Protein

Background

LRRC4B, also known as netrin-G ligand 3 (NGL-3), is a transmembrane protein containing leucine-rich repeats that mediate synaptic adhesion, neuronal development, and signaling processes. It interacts with netrin-G proteins to form trans-synaptic connections that promote synapse formation, stabilization, and excitatory synaptic transmission in the central nervous system. LRRC4B is highly expressed in the brain, particularly in regions regulating learning, memory, and synaptic plasticity, where it supports the organization of neural circuits and dendritic spine maturation. Dysregulation of LRRC4B is associated with neurodevelopmental disorders, including autism spectrum disorders (ASD) and intellectual disabilities, due to impaired synaptic connectivity and function. Functional studies in knockout models demonstrate synaptic defects, abnormal neuronal morphology, and reduced synaptic transmission, emphasizing its essential role in maintaining excitatory synapse structure and function during brain development.