Molecular cloning and characterization of the promoter region of the porcine apolipoprotein E gene.
Apolipoprotein E (APOE), a component of lipoproteins plays an important role in the transport and metabolism of cholesterol, and is associated with hyperlipoproteinemia and Alzheimer's disease. In order to further understand the characterization of APOE gene, the promoter of APOE gene of Landrace pigs was analyzed in the present study. The genomic structure and amino acid sequence in pigs were analyzed and found to share high similarity in those of human but low similarity in promoter region. Real-time PCR revealed the APOE gene expression pattern of pigs in diverse tissues. The highest expression level was observed in liver, relatively low expression in other tissues, especially in stomach and muscle. Furthermore, the promoter expressing in Hepa 1-6 was significantly better at driving luciferase expression compared with C2C12 cell. After analysis of porcine APOE gene promoter regions, potential transcription factor binding sites were predicted and two GC signals, a TATA box were indicated. Results of promoter activity analysis indicated that one of potential regulatory elements was located in the region -669 to -259, which was essential for a high expression of the APOE gene. Promoter mutation and deletion analysis further suggested that the C/EBPA binding site within the APOE promoter was responsible for the regulation of APOE transcription. Electrophoretic mobility shift assays also showed the binding site of the transcription factor C/EBPA. This study advances our knowledge of the promoter of the porcine APOE gene.
Key Laboratory for Farm Animal Genetic Resources and Utilization of Ministry of Agriculture of China, Institute of Animal Science (IAS), Chinese Academy of Agricultural Science (CAAS), Beijing, 100193, People's Republic of China, xiajihan@126.com.
Jihan
J
Xia
Bingjun
B
Hu
Yulian
Y
Mu
Leilei
L
Xin
Shulin
S
Yang
Kui
K
Li
D000818:Animals; D001057:Apolipoproteins E / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D022762:CCAAT-Enhancer-Binding Proteins / Q000378:metabolism; D002460:Cell Line; D003001:Cloning, Molecular; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D059372:Nucleotide Motifs; D009928:Organ Specificity / Q000235:genetics; D056510:Position-Specific Scoring Matrices; D011401:Promoter Regions, Genetic; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013552:Swine; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation
D001057:Apolipoproteins E; D022762:CCAAT-Enhancer-Binding Proteins; D014157:Transcription Factors