Mannose-binding lectin 1 haplotypes influence serum MBL-A concentration, complement activity, and milk production traits in Chinese Holstein cattle

Abstract

Mannose-binding lectin (MBL) is a member of the collectin protein family that binds a broad range of microorganisms and activates the lectin-complement pathway of innate immunity. MBL deficiency is associated with an increased risk for various infections and arises from five polymorphisms in the promoter and first exon of the MBL gene in humans. In this study, three novel single-nucleotide polymorphisms (SNPs) in the promoter region and two previously reported SNPs in exon 2 of the MBL1 gene were detected using PCR single-strand conformation polymorphism, restriction fragment length polymorphism, and DNA sequencing in 537 cattle from three Chinese breeds. Analysis of the genotypes and haplotypes was used to investigate the polymorphisms and their possible implications, especially their association with serum MBL-A levels, complement activity (CH50 and ACH50), and milk production traits was investigated. The g.2651G > A SNP in exon 2 affected the serum MBL-A concentrations and the serum CH50 values, whereas the g.-1330G > A SNP significantly affected CH50 and the somatic cell scores (SCSs). Statistical analysis revealed that cows with the ATGGC/ACAAC combined genotype and those with the AAGGT/ACGGT combined genotype exhibited the lowest and highest SCSs, respectively. Serum antibacterial activities were also conducted to verify the effect of the SNPs on resistance to mastitis pathogens. Results of real-time PCR showed that the liver of cows with clinical mastitis exhibited a higher MBL1 expression compared with healthy ones (P < 0.05). Findings of this study indicate that the MBL1 gene possibly contributes to bacterial infection resistance and can be used as a molecular marker of milk production traits to control mastitis.

Adjuvant effects of mannose-binding lectin ligands on the immune response to infectious bronchitis vaccine in chickens with high or low serum mannose-binding lectin concentrations

“…Beside sugars, MBL has also been found to bind to phospholipids, nucleic acids, and non-glycosylated proteins (Ip et al 2009). The MBL genes in human (Madsen et al 1994(Madsen et al , 1995Steffensen et al 2000;Sumiya et al 1991), porcine (Juul-Madsen et al 2011a;Lillie et al 2007), bovine (Liu et al 2011) and chickens (Kjaerup et al 2013) have been found to have polymorphisms resulting in wide variations in MBL serum levels in the organisms.…”

MBL1 genotypes in wild boar populations from Sweden, Austria, the Czech Republic, and Japan

“…In Chinese Holstein cattle, polymorphism in the MBL1 gene has been found to influence MBL-A serum concentration, complement activity, and milk production traits. Also, results of correlation analysis suggest that the MBL1 gene is significantly correlated with cattle mastitis (Liu et al, 2011). In humans, three variant, coding MBL2 alleles with decreasing effect on MBL concentration in serum are known.…”

Association study of single nucleotide polymorphisms inJAK2andSTAT5Bgenes and their differential mRNA expression with mastitis susceptibility in Chinese Holstein cattle

“…On the other hand, SNPs in the exons and promoter regions of the JAK2 and STAT5B genes can change the RNA stability of their target genes (Liu et al . ). In our initial work, a total three SNPs, including those in intron 4, exon16 and exon 19, were identified in bovine STAT5B .…”