Polymorphism, Expression of Natural Resistance-associated Macrophage Protein 1 Encoding Gene (<i>NRAMP1</i>) and Its Association with Immune Traits in Pigs

Abstract

Natural resistance-associated macrophage protein 1 encoding gene (NRAMP1) plays an important role in immune response against intracellular pathogens. To evaluate the effects of NRAMP1 gene on immune capacity in pigs, tissue expression of NRAMP1 mRNA was observed by real time quantitative polymerase chain reaction (PCR), and the results revealed NRAMP1 expressed widely in nine tissues. One single nucleotide polymorphism (SNP) (ENSSSCG00000025058: g.130 C>T) in exon1 and one SNP (ENSSSCG00000025058: g.657 A>G) in intron1 region of porcine NRAMP1 gene were demonstrated by DNA sequencing and PCR-RFLP analysis. A further analysis of SNP genotypes associated with immune traits including contain of white blood cell (WBC), granulocyte, lymphocyte, monocyte (MO), rate of cytotoxin in monocyte (MC) and CD4/CD8 T lymphocyte subpopulations in blood was carried out in four pig populations including Large White and three Chinese indigenous breeds (Wannan Black, Huai pig and Wei pig). The results showed that the SNP (ENSSSCG00000025058: g.130 C>T) was significantly associated with level of WBC % (p = 0.031), MO% (p = 0.024), MC% (p = 0.013) and CD4−CD8+ T lymphocyte (p = 0.023). The other SNP (ENSSSCG00000025058: g.657 A>G) was significantly associated with the level of MO% (p = 0.012), MC% (p = 0.019) and CD4−CD8+ T lymphocyte (p = 0.037). These results indicate that the NRAMP1 gene can be regarded as a molecular marker for genetic selection of disease susceptibility in pig breeding.

Nramp1 gene expression in different tissues of Meishan piglets from newborn to weaning

“…Results indicated that Nramp1 was expressed in all tissues tested regardless of individual tissue specificity, although expression at different developmental stages did vary significantly. This finding was consistent with Nramp1 tissue expression among hybrid boar and indigenous Tibetan and Huai breeds, but differed from that in foreign pig breeds (Zhang et al, 2000;Ying and Zhang, 2007;Chen and Liu, 2009;Ding et al, 2014). Nramp1 was expressed at relatively high levels in the spleen, which is the largest immune response-related organ in the body that develops and produces macrophages and lymphocytes, and is key to both humoral and cellular immunity in Chinese pig breeds.…”

“…Many studies have shown that polymorphism of pig Nramp1 is correlated with both immune function (Wu et al, 2008) and diarrhea in piglets (Gu, 2006;Liu et al, 2010;Zhao et al, 2013). Among indigenous Chinese pig breeds (specifically Tibetan and Huai pigs) and in hybrid boar, Nramp1 gene expression exists in all tissues (Ying and Zhang, 2007;Chen and Liu, 2009;Ding et al, 2014), whereas some tissue specificity was reported in foreign pigs, in which Nramp1 was not expressed in ileum, colon, or brain tissues (Zhang et al, 2000). Despite a correlation between polymorphism of Nramp1 and diarrhea in piglets, and some profile variation in tissue expression data, it has not been determined whether expression of Nramp1 is related to general disease resistance in piglets (nonspecific immunity).…”

Genomic analysis reveals selection signatures of the Wannan Black pig during domestication and breeding

“…Our previous research on MicroRNA-21 and microRNA-214 revealed that they play an important role in the regulation of estrous during porcine reproduction [20]. Analysis of the natural resistance-associated macrophage protein 1 encoding gene in Wannan black pig and Yorkshire identified a single nucleotide polymorphism, which was significantly associated with level of white blood cell % (p = 0.04), monocyte % (p = 0.024), rate of cyotoxin in monocyte % (p = 0.013) and CD4 -CD8 + T lymphocyte (p = 0.023) elucidating the disease-resistance of Wannan black pig compared to Yorkshire [19]. Our previous and whole-genome resequencing results suggest that the genes detailed above played crucial roles in Wannan Black pig domestication by altering the functional regulation of the immune system, environmental adaption, fertility, and the digestive system.…”

“…Our previous study about retinol-binding protein 4 (RBP4) gene and cholesteryl estertransfer protein (CETP) gene in Wannan black pig revealed that RBP4 was significantly associated with average back-fat thickness and meat color b* value, and identified a mutation in CETP, which had significant effects on the expression in liver and correlated positively with serum lipid and meat fat phenotypes [17,18]. Moreover, other genes and microRNAs related with immune traits and fertility have been identified [19,20]. However, these studies were performed only on a few genes and microRNAs.…”

Polymorphism of the retinol-binding protein 4 gene (RBP4) and its association with carcass and meat quality traits in swine

“…This may be due to the sample size being smaller and the locus being conservative in the Huoshouhei breed (17). The genotypic frequency of AA exceeded 50% in the Anqingliubai, Wannanhei, and Wei populations, and the PIC values of different sites in the RBP4 gene ranged between 0.25 and 0.5, indicating moderate polymorphism and a high probability of genetic variation.…”