SNP detection of TLR8 gene, association study with susceptibility/resistance to GCRV and regulation on mRNA expression in grass carp, Ctenopharyngodon idella. Issue 1 (March 2015)

• Record Type: Journal Article
• Authors: Su, Juanjuan; Su, Jianguo; Shang, Xueying; Wan, Quanyuan; Chen, Xiaohui; Rao, Youliang
• Is Part Of: Fish & shellfish immunology. Volume 43:Issue 1(2015:Mar.)
• Page Start: 1
• Page End: 12
• Publication Date: 2015-03
• Subjects: Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2014.12.005
• Languages: English
• ISSNs: 1050-4648

Abstract

<abstract xml:lang="en" abstract-type="author" id="abs0010"> <title id="sectitle0010">Abstract</title> <sec> <p id="abspara0010">Toll-like receptor 8 (TLR8), a prototypical intracellular member of TLR family, is generally linked closely to antiviral innate immune through recognizing viral nucleic acid. In this study, 5′-flanking region of <italic>Ctenopharyngodon idella TLR8</italic> (<italic>CiTLR8</italic>), 671 bp in length, was amplified and eight SNPs containing one SNP in the intron, three SNPs in the coding region (CDS) and four SNPs in the 3′-untranslated region (UTR) were identified and characterized. Of which 4062 A/T was significantly associated with the susceptibility/resistance to GCRV both in genotype and allele (<italic>P</italic> < 0.05), while 4168 C/T was extremely significantly associated with that (<italic>P</italic> < 0.01) according to the case (susceptibility)–control (resistance) analysis. Following the verification experiment, further analyses of mRNA expression, linkage disequilibrium (LD), haplotype and microRNA (miRNA) target site indicated that 4062 A/T and 4168 C/T in 3′-UTR might affect the miRNA regulation, while the exertion of antiviral effects of 4062 A/T might rely on its interaction with other SNPs. Additionally, the high-density of SNPs in 3′-UTR might reflect the specific biological functions of 3′-UTR. And also, the mutation of 747 A/G in intron changing the potential transcriptional factor-binding sites (TFBS) nearby might affect the expression of <italic>CiTLR8</italic> transcriptionally or post-transcriptionally. Moreover, as predicted, the A/G transition of the only non-synonymous SNP (3846 A/G) in CDS causing threonine/alanine variation, could shorten the length of the α-helix and ultimately affect the integrity of the Toll-IL-1 receptor (TIR) domain. The functional mechanism of 3846 A/G might also involve a threonine phosphorylation signaling. This study may broaden the knowledge of <italic>TLR</italic> polymorphisms, lay the foundation for further functional research of <italic>CiTLR8</italic> and provide potential markers as well as theoretical basis for resistance molecular breeding of grass carp against GCRV.</p> </sec> </abstract>