Key component of innate and adaptive immunity. TLRs (Toll- like receptors) control host immune response against pathogens through recognition of molecular patterns specific to microorganisms. TLR3 is a nucleotide-sensing TLR which is activated by double-stranded RNA, a sign of viral infection. Acts via the adapter TRIF/TICAM1, leading to NF-kappa-B activation, IRF3 nuclear translocation, cytokine secretion and the inflammatory response. {ECO:0000269|PubMed:12471095, ECO:0000269|PubMed:12539043, ECO:0000269|PubMed:16043704, ECO:0000269|PubMed:16144834, ECO:0000269|PubMed:16720699, ECO:0000269|PubMed:16858407, ECO:0000269|PubMed:17178723, ECO:0000269|PubMed:18172197, ECO:0000269|PubMed:22611194}. This is the function of ENSG00000164342 (TLR3, toll like receptor 3).