Enables lipopolysaccharide binding activity and phosphatidylinositol 3-kinase binding activity. Involved in several processes, including detection of stimulus involved in sensory perception of pain; immune response-regulating signaling pathway; and response to steroid hormone. Located in cell surface and cytoplasm. Colocalizes with membrane raft. Used to study several diseases, including carotid stenosis; ileitis; neuropathy (multiple); obesity; and renal fibrosis. Biomarker of several diseases, including kidney failure (multiple); pancreatitis (multiple); perinatal necrotizing enterocolitis; pulpitis; and sciatic neuropathy. Human ortholog(s) of this gene implicated in several diseases, including allergic contact dermatitis (multiple); artery disease (multiple); autoimmune disease (multiple); eye disease (multiple); and lung disease (multiple). Orthologous to human TLR4 (toll like receptor 4). [provided by Alliance of Genome Resources, Apr 2022]