Innate pathway activation is fundamental for early anti-viral defense in fish, but currently there is insufficient understanding of how salmonid fish identify viral molecules and activate these pathways. The Toll-like receptor (TLR) is believed to play a crucial role in host defense of pathogenic microbes in the innate immune system. In the present study, the full-length cDNA of Salmo salar TLR3 (ssTLR3) was cloned. The ssTLR3 cDNA sequence was 6071 bp long, containing an open reading frame of 2754 bp and encoding 971 amino acids.
Toll-like receptor 3 (TLR3) variants in mainland northern Chinese patients with polypoidal choroidal vasculopathy (PCV) and neovascular age-related macular degeneration (nAMD) were investigated. The complete genes of TLR3, including all exons and the promoter region, were assessed using direct sequencing technology of 284 unrelated mainland northern Chinese individuals: 96 nAMD patients, 92 PCV patients, and 96 controls. Six single nucleotide polymorphisms were identified: rs5743303, rs5743305, rs5743312, rs3775291, rs3775290, and rs6830345.
Toll-like receptor 3 (TLR3) recognizes double-stranded RNA, which is a molecular signature of viruses, and plays a pivotal role in host defense against viral invasion. Polymorphisms in the human TLR3 gene have been shown to affect the receptor function and to be associated with a variety of diseases, suggesting correlations between TLR3 polymorphisms and the disease resistance/susceptibility in pigs.