Identification of the prion-related protein gene (PRNT) sequences in various species of the Cervidae family

Chronic wasting disease (CWD) is caused by abnormal deleterious prion protein (PrP^Sc), and transmissible spongiform encephalopathy occurs in the Cervidae family. In recent studies, the susceptibility of prion disease has been affected by polymorphisms of the prion gene family. However, the study of the prion-related protein gene (PRNT) is rare, and the DNA sequence of this gene was not fully reported in all Cervidae families. In the present study, we amplified and first identified PRNT DNA sequences in the Cervidae family, including red deer, elk, sika deer and Korean water deer, using polymerase chain reaction (PCR). We aligned nucleotide sequences of the PRNT gene and the amino acid sequences of prion-related protein (Prt) protein among several species. In addition, we performed phylogenetic analysis to measure the evolutionary relationships of the PRNT gene in the Cervidae family. Furthermore, we performed homology modeling of the Prt protein using SWISS-MODEL and compared the structure of Prt protein between sheep and the Cervidae family using the Swiss-PdbViewer program. We obtained much longer PRNT sequences of red deer compared to the PRNT gene sequence registered in GenBank. Korean water deer denoted more close evolutionary distances with goats and cattle than the Cervidae family. We found 6 Cervidae family-specific amino acids by the alignment of Prt amino acid sequences. There are significantly different distributions of hydrogen bonds and the atomic distance of the N-terminal tail and C-terminal tail between sheep and the Cervidae family. We also detected the mRNA expression of PRNT gene in 3 tissues investigated. To our knowledge, this report is the first genetic study of the PRNT gene in the Cervidae family.