a cell surface receptor involved in lymphocyte activation and neural function. LAG3 expressed on neurons is a receptor that binds extracellular Alpha-synuclein fibrils (PFF) with high affinity, leading to its endocytosis. LAG3 facilitates the neuron-to-neuron spread of PFF and its associated neural toxicity. Binds to HLA class-II antigens. Two isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Cellular Component: external side of plasma membrane; integral component of membrane; plasma membrane
Molecular Function: antigen binding; MHC class II protein binding; transmembrane receptor activity
Biological Process: antigen processing and presentation of exogenous peptide antigen via MHC class II; cell surface receptor signaling pathway; negative regulation of interleukin-2 biosynthetic process; negative regulation of T cell activation; positive regulation of natural killer cell mediated cytotoxicity