Đặng Quốc Bảo
Senior Member
GENE CLONING PRION (PrP) FROM KOREAN BOVINE
Đặng Quốc Bảo
A prion — short for proteinaceous infectious particle — is a unique type of infectious agent, as it is made only of protein. Prion diseases, also called Transmissible Spongiform Encephalopathies(TSE), are neurodengenerative diseases that affect ether animal or human.Some of diseases is decribled in Table 1. (Prusiner,1998).
In mammals, a normal prion protein (PrPc) is a normal cellular protein that is expressed in the neurons and glia of the brain and spinal cord, as well as in several peripheral tissues and leukocyte. PrPc also has some charecteristic still unknown.( Kang et al 2004). PrP play a central role in the transmission and pathogenesis of prion disease, but the abnormal isoform is an essential component of the prion particle (Prusiner, 1991). Although PrPc and PrPsc have the same amino acid sequence, they are different in structural conformation. PrPc can be changed into the disease-causing isoform(PrPsc) so the key to understanding the pathogenesis of this disease is the conformatinal conversion from PrPc( cell surface glycoprotein) to pathogenesis isoform PrPsc. PrPc is rich in α- helical (about 40%) content and has little β-sheet structure, whereas PrPsc has less α- helical (about 30%) content and high β-sheet(about 45%) structure(Pan et al. 1993; Pergami, P., Jaffe, H. & Safar, J. 1996). This difference in secondary structure makes the sensitivity to proteinase K (PK), and solubility are different( Corsaro et al,2002)
Bovine spongiform encephalopathy (BSE) is one of the most notable prion diseases. After infecting into bovine, the average time for BSE incubating is about 5 years. Therefore the disaster was not recognized until BSE infected more than 160,000 cattle, primarily dairy cows over 1980s (Anderson et al. 1996). Some study showed that BSE is a massive common-source epidemic caused by meat and bone meal(MBM) fed primarily to dairy cows(Nathanson et al. 1997; Wilesmith et al. 1991). The MBM was prepared from the offal of sheep, cattle, pigs, and chickens as a high-protein nutritional supplement.
BSE is not only potential risk on bovine but also on human. Believed related to BSE, variant Creutzfeldt-Jakob disease (vCJD) was first reported in March 1996 in the UK. In contrast to the classical forms of CJD, vCJD has affected younger patients (average age 29 years, as opposed to 65 years), has a relatively longer duration of illness (median of 14 months as opposed to 4.5 months) and is strongly linked to exposure, probably through food, to BSE. Similarities observed between the strain of the agent responsible for vCJD and those of BSE and closely related agents transmitted naturally and experimentally to different animal species, are consistent with the hypothesis discussed during two 1996 WHO consultations: that the cluster of vCJD cases is due to the same agent that caused BSE in cattle. (WHO, 2002)
After the first outbreak in England in 1986, BSE spread throughout only Europe up to 2000. However, since 2001, it is spreading to counntries such as Japan (2001), Israel (2002), Canada (2003), and the United States (case found in Canadian cattle in 2003. OIE classifies the US as a BSE- free country). There were a total of 189,000 outbreaks in 23 countries (excluding the US) up to February 2005. Until now Korea is free from BSE (Tae-Yung Kim et. al,2005), but the BSE is high risk damage society. The study on BSE is absolutelly essential.
In this study under the instruction of professor Kwon Moosik and associate professor Nguyen Ngoc Tuan, we are working on full gene of prion . As the first step of prion research, we are cloned full gene of prion encoding bovine prion protein from Korean bovine.
PrP gene is cloned from cDNA of Korean bovine genome by PCR following 2 primers forward and reverses primer (Figure 2). Cloned gene is transmitted in to pGEMT easy vector. Recombination vector is transformed into E.coli. Recombinant vector is sequenced.
After successful cloning, we change FR to expression vector. Protein that collected will be studied.
Đặng Quốc Bảo
A prion — short for proteinaceous infectious particle — is a unique type of infectious agent, as it is made only of protein. Prion diseases, also called Transmissible Spongiform Encephalopathies(TSE), are neurodengenerative diseases that affect ether animal or human.Some of diseases is decribled in Table 1. (Prusiner,1998).
In mammals, a normal prion protein (PrPc) is a normal cellular protein that is expressed in the neurons and glia of the brain and spinal cord, as well as in several peripheral tissues and leukocyte. PrPc also has some charecteristic still unknown.( Kang et al 2004). PrP play a central role in the transmission and pathogenesis of prion disease, but the abnormal isoform is an essential component of the prion particle (Prusiner, 1991). Although PrPc and PrPsc have the same amino acid sequence, they are different in structural conformation. PrPc can be changed into the disease-causing isoform(PrPsc) so the key to understanding the pathogenesis of this disease is the conformatinal conversion from PrPc( cell surface glycoprotein) to pathogenesis isoform PrPsc. PrPc is rich in α- helical (about 40%) content and has little β-sheet structure, whereas PrPsc has less α- helical (about 30%) content and high β-sheet(about 45%) structure(Pan et al. 1993; Pergami, P., Jaffe, H. & Safar, J. 1996). This difference in secondary structure makes the sensitivity to proteinase K (PK), and solubility are different( Corsaro et al,2002)
Bovine spongiform encephalopathy (BSE) is one of the most notable prion diseases. After infecting into bovine, the average time for BSE incubating is about 5 years. Therefore the disaster was not recognized until BSE infected more than 160,000 cattle, primarily dairy cows over 1980s (Anderson et al. 1996). Some study showed that BSE is a massive common-source epidemic caused by meat and bone meal(MBM) fed primarily to dairy cows(Nathanson et al. 1997; Wilesmith et al. 1991). The MBM was prepared from the offal of sheep, cattle, pigs, and chickens as a high-protein nutritional supplement.
BSE is not only potential risk on bovine but also on human. Believed related to BSE, variant Creutzfeldt-Jakob disease (vCJD) was first reported in March 1996 in the UK. In contrast to the classical forms of CJD, vCJD has affected younger patients (average age 29 years, as opposed to 65 years), has a relatively longer duration of illness (median of 14 months as opposed to 4.5 months) and is strongly linked to exposure, probably through food, to BSE. Similarities observed between the strain of the agent responsible for vCJD and those of BSE and closely related agents transmitted naturally and experimentally to different animal species, are consistent with the hypothesis discussed during two 1996 WHO consultations: that the cluster of vCJD cases is due to the same agent that caused BSE in cattle. (WHO, 2002)
After the first outbreak in England in 1986, BSE spread throughout only Europe up to 2000. However, since 2001, it is spreading to counntries such as Japan (2001), Israel (2002), Canada (2003), and the United States (case found in Canadian cattle in 2003. OIE classifies the US as a BSE- free country). There were a total of 189,000 outbreaks in 23 countries (excluding the US) up to February 2005. Until now Korea is free from BSE (Tae-Yung Kim et. al,2005), but the BSE is high risk damage society. The study on BSE is absolutelly essential.
In this study under the instruction of professor Kwon Moosik and associate professor Nguyen Ngoc Tuan, we are working on full gene of prion . As the first step of prion research, we are cloned full gene of prion encoding bovine prion protein from Korean bovine.
PrP gene is cloned from cDNA of Korean bovine genome by PCR following 2 primers forward and reverses primer (Figure 2). Cloned gene is transmitted in to pGEMT easy vector. Recombination vector is transformed into E.coli. Recombinant vector is sequenced.
After successful cloning, we change FR to expression vector. Protein that collected will be studied.
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