Differences in distribution of single nucleotide polymorphisms among intracellular pattern recognition receptors in pigs

Abstract

Pathogens localized extracellularly or incorporated into endosomes are recognized mainly by Toll-like receptors, whereas pathogens and pathogen-derived molecules that invade into the cytoplasm of host cells typically are recognized by intracellular pattern recognition receptors (PRRs), such as retinoic acid-inducible gene (RIG)-like helicases (RLHs) and nucleotide-binding oligmerization domain (NOD)-like receptors (NLRs). RIG-I and melanoma differentiation-associated gene 5 (MDA5), which belong to the RLH family, recognize viral genomic RNA, whereas NOD2, a member of the NLR family, responds to microbial peptidoglycans. These receptors may play an important role in pig opportunistic infectious diseases, such as pneumonia and diarrhea, which markedly impair livestock productivity, such that polymorphisms of these receptor genes are potential targets of pig breeding to increase disease resistance. Here, we report single nucleotide polymorphisms (SNPs) in porcine DDX58, IFIH1, and NOD2, which encode RIG-I, MDA5, and NOD2, respectively. Interestingly, compared with DDX58 and IFIH1, NOD2 abounded in nonsynonymous SNPs both throughout the coding sequence and in sequences encoding domains important for ligand recognition, such as helicase domains for RIG-I and MDA5 and leucine-rich repeats in NOD2. These differences in the distribution of SNPs in intracellular PRRs may parallel the diversity of their ligands, which include nucleic acids and peptidoglycans.

The impact of breed and tissue compartment on the response of pig macrophages to lipopolysaccharide

“…These differences might be associated with polymorphic variation in miRNA recognition sites reported elsewhere [31]. Significant levels of protein-coding polymorphism have already been reported amongst pig pattern intracellular and extracellular recognition receptors [19,32]. It is striking that such genes are DR between the macrophage populations, and highly variable between individuals.…”

RETRACTED ARTICLE: Analysis of protein-protein interaction network and functional modules on primary osteoporosis

“…DDX58 and IFIH1 are reported respectively to have four and two SNPs that lead to structural or polar differences in the mutated amino acid compared with the native residue [26]. ISG15, as the ubiquitin-like modifier, probably acts as one potential downstream mediator of Fzd9 (frizzled homolog 9) in the control of bone formation [27].…”

The Immunopathology of Sepsis: Pathogen Recognition, Systemic Inflammation, the Compensatory Anti‐Inflammatory Response, and Regulatory T Cells

“…Thus, TLRs 1–10 have been cloned and sequenced; surface and endosomal TLRs have been detected—both by PCR and immunohistochemistry—in a variety of porcine tissues and enhanced expression demonstrated in response to a number of infectious agents and PAMPs . Members of the NLR family have also been identified and current research suggests that porcine PRR signaling pathways are similar to those of other mammalian species …”

“…Ongoing research is attempting to identify whether or not certain single nucleotide polymorphisms (SNPs) of PRRs can be related to the propensity for particular canine breeds to develop IBD and other immune‐mediated diseases . The analysis of SNPs in PRR‐encoding genetic sequences is also an exciting field of research in large animals, laying the foundation for the breeding of livestock with enhanced disease resistance and the design of vaccines better able to target dendritic cells . Finally, recent work has documented the expression of an ortholog of human “triggering receptor expressed on myeloid cells‐1” (TREM‐1) by canine neutrophils .…”