Authors: Jienan Cheng Jun Li Wenxin Zhang Yafei Cai Genlin Wang
Publish Date: 2012/06/26
Volume: 39, Issue: 10, Pages: 9601-9612
Abstract
Mastitis is an unsolved human challenge all dairy farms facing with which leads to immeasurable economic loss to the farmers LBP gene plays a vital role in the innate immune recognition of Gramnegative bacterium that is a major cause of bovine clinical mastitis but little is known about LBP mutations and their effects on cows’ susceptibility to clinical mastitis In this study PCRSSCP method was adopted to analyze SNPs of LBP gene in Chinese Holstein for the first time 17 SNPs were found in the promoter core region exon1 exon2 exon3 exon4 and exon8 The mutation g−81C → T in promoter leads to an AP2 binding site lost Two mutations g11T → C 4 Leu → Ser and g68G → C 23Gly → Ala in signal peptide brought about molecular secondary structural change meanwhile g11T → C made a Big1 domain lost and there was an Nmyristoylation site at the g68G/C locus The three mutations above were in complete linkage disequilibrium in allele A In mature LBP protein five mutations were found g3034G → A36Asp → Asn g3040A → G38Asn → Asp g3056T → C43Ile → Thr in allele D g4619G → A67Ala → Thr in allele F 19975G → A 282Val → Met in allele J And SNPs in allele D and F were in complete linkage disequilibrium also in which 38Asn → Asp and 67Ala → Thr influenced the protein secondary structure Prediction of the 3D structure shows mutations 36Asp → Asn 38Asn → Asp and 43 Ile → Thr were on the concave surface of LBP protein at barrelN 67Ala → Thr was in the apolar pocket at barrelN Motif analysis shows 36Asp → Asn causes loss of a CK2 phosphorylation site 67 Ala → Thr forms a new PKC phosphorylation site And 43Ile → Thr 67Ala → Thr made hydrophobic amino acids to be hydrophilic amino acids Interestingly the morbidity of AB mixed type g−81C/T g11T/C g68G/C CD mixed type g3034G/A g3040A/G g3056T/C and EF mixed type g4619G/A genotype cows are significant higher than others in this study P 001 and it can be deduced that the SNPs in these 3 genotypes might affect the secretion of LBP protein and regulate the binding ability of LBP protein to LPS Taken together it is revealed that these SNPs may hold the secret of susceptibility to clinical mastitis in Chinese HolsteinThis study was supported by “the Twelfth FiveYear Plan” National Science and Technology Research Program of China 2011BAD28B02 2012BAD12B10 Jiangsu Agricultural Science Program SX2011189 Anhui and Wuhu Natural Science and Technology Program 1208085MC41 10020303043 2010
Keywords: