Key Laboratory for Animal Genetics, Breeding, Reproduction and Molecular Design of Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Jiangsu, Yangzhou 225009, China.

Key Laboratory for Animal Genetics, Breeding, Reproduction and Molecular Design of Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Jiangsu, Yangzhou 225009, China.

Key Laboratory for Animal Genetics, Breeding, Reproduction and Molecular Design of Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Jiangsu, Yangzhou 225009, China.

Changzhou Fenghua Animal Husbandry Co., LTD, Jiangsu, Changzhou 213000, China.

Changzhou Fenghua Animal Husbandry Co., LTD, Jiangsu, Changzhou 213000, China.

Key Laboratory for Animal Genetics, Breeding, Reproduction and Molecular Design of Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Jiangsu, Yangzhou 225009, China.

Key Laboratory for Animal Genetics, Breeding, Reproduction and Molecular Design of Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Jiangsu, Yangzhou 225009, China.
Pig ,APN ,Promoter ,Methylation ,

For analyzing the correlation between APN (encodingaminopeptidase N) expression and Escherichia coli F18 adhesion and the regulation of APN promoter region methylation in weaning pigs (Susscrofa),we used bisulfite sequencing PCR (BSP) and quantitative real-time PCR (qPCR) to detected the methylation status of a CpG island in the APN promoter region and APN mRNA expression in intestinal tissue of Sutai piglets that resistant or sensitive to E. coli F18. The APN expression in the duodenum and jejunum was significantly lower in the resistant group than in the sensitive group (P < 0.01). In the APN promoter CpGisland there were 16 CpG sites possessing different levels of methylation, and the average methylation levels of the amplified fragment were lower in the resistant group compared with the sensitive group. There was a positive correlation between methylation levels of each CpG site and mRNA expression: the methylation levels of mC-1, mC-4, mC-6, mC-8, mC-9 and mC-15 were significantly and positively correlated with mRNA expression (P < 0.05). Further analysis indicated that mC-1 was in transcription factor binding sites for TEC1 and Sp1; mC-6 in Sp1 and AP-2; mC-8 in CTE-BP1 and CPE bind. We speculated that lower APN expression might be beneficial for developing resistance to E. coli F18. mC-1, mC-6 and mC-8 might be key sites regulating this gene expression. Transcription factors TEC1, Sp1, AP-2, CTEBP1and CPE might play an important role in regulating APN expression.

6 , 10 , 2016