Novel single nucleotide polymorphisms in the specific protein 1 binding site of the bovine PRNP promoter in Japanese Black cattle: impairment of its promoter activity.
Susceptibility to transmissible spongiform encephalopathy and different alleles of the prion protein gene (PRNP) of humans and sheep are associated. A tentative association between PRNP promoter polymorphisms and bovine spongiform encephalopathy (BSE) susceptibility has been reported in German cattle, whereas none of the known polymorphisms within the bovine PRNP-coding sequence affect BSE susceptibility. In the present study, novel single nucleotide polymorphisms located in the 5'-flanking region of bovine PRNP affecting its expression were demonstrated in Japanese Black cattle. We sequenced exon 1, and the approximately 200-bp 5'-flanking region of the PRNP translation initiation site containing the proximal promoter of PRNP was harvested. We identified 7 single nucleotide polymorphisms: -184A-->G, -141T-->C, -85T-->G, -47C-->A, -6C-->T, +17C-->T and +43C-->T. Six segregated haplotypes in the population were cloned into luciferase-expressing plasmids, transfected into N2a cells, and their reporter activities were measured 48 h after transfection. Six haplotypes showed a decreased expression level including -6C-->T in specific protein 1 binding site (p < 0.05) or -141T-->C (p < 0.01) at 48 h compared with the wild-type haplotype. These results advocate that certain polymorphisms such as specific protein 1 binding site polymorphisms in the bovine PRNP promoter region in Japanese Black cattle could influence promoter activity, suggesting that breeding cattle with such substitutions may be a useful approach in reducing BSE risk.
Nakamura
Izuru
I
Department of Molecular Immunology, School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan.
Xue
Guangai
G
Sakudo
Akikazu
A
Saeki
Keiichi
K
Matsumoto
Yoshitsugu
Y
Ikuta
Kazuyoshi
K
Onodera
Takashi
T
D024506:5' Flanking Region / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002417:Cattle; D003001:Cloning, Molecular; D016643:Encephalopathy, Bovine Spongiform / Q000235:genetics*; D015870:Gene Expression; D017930:Genes, Reporter; D020022:Genetic Predisposition to Disease; D006239:Haplotypes; D008156:Luciferases / Q000096:biosynthesis; D008969:Molecular Sequence Data; D020641:Polymorphism, Single Nucleotide; D011328:Prions / Q000235:genetics*; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA
D011328:Prions; D008156:Luciferases