Chinese
Little-fat-tail Sheep Prion Protein Gene Belongs to PrPARHGenotype
LI Yun-Min, TIAN Bo*
( Institute of Microbiology,
the Chinese Academy of Sciences, Beijing 100080, China )
Abstract
The genomic DNA was extracted from
lymphocytes of peripheral blood of Chinese little-fat-tail sheep. The prion
protein gene(PrPc) was amplified by polymerase chain
reaction. The PCR products were cloned into pUC19 plasmid and was sequenced.
The results indicated that 771 bp amplified fragment contains the entire sheep PrPc
coding sequence. There were 7 base pairs different with the reported sheep PrPc
sequence, leading to three amino
acids changes in the protein. It is show that its genotype is PrP, and these three polymorphisms may be
linked to susceptibility or resistance to scrapie infection. Mature sheep prion
protein gene was inserted into pET30a and expressed in E.coli, and 23 kD
PrP25～231 protein was obtained. Recombinant PrP25～231 protein was purified by
inclusion body washing,
ion-exchange chromatography, reverse phase chromatography. Results of
SDS-PAGE and Western blot showed that the purified PrP25～231 was obtained.
Key words sheep PrP gene; sequence analysis;
polymorphism; expression;
purification
*Corresponding author: Te,
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