The propagation of hamster-adapted scrapie PrPSc can be enhanced by reduced pyridine nucleotide in vitro.
Transmissible spongiform encephalopathies (TSEs), or prion diseases, are fatal neurodegenerative disorders caused by an infectious agent termed a prion, which can convert normal cellular prion protein (PrP(C)) into a pathologically misfolded isoform (PrP(Sc)). Taking advantage of protein misfolding cyclic amplification (PMCA), a series of experiments was conducted to investigate the possible influences of pyridine nucleotides on the propagation activities of hamster-adapted scrapie agents 263K and 139A in vitro using normal hamster brain homogenates and recombinant hamster PrP as the substrates. The results showed that PrP(Sc) from both scrapie agent 263K- and 139A-infected brains propagated more efficiently in PMCA with the addition of reduced NADPH, showing an obvious dose-dependent enhancement. Reduced NADH also prompted PrP(Sc) propagation, whereas NADP, NAD and vitamin C failed. Moreover, following incubation with NADPH, recombinant hamster PrP could be efficiently converted into the proteinase K-resistant form when exposed to the trace of PrP(Sc) from infected hamsters. Our data provide evidence that the reduced pyridine nucleotide plays an important role in the propagation of prion and this process seems to target PrP(C) molecules.
Shi
Song
S
State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Viral Disease Control and Prevention, Beijing, China.
Dong
Chen-Fang
CF
Tian
Chan
C
Zhou
Rui-Min
RM
Xu
Kun
K
Zhang
Bao-Yun
BY
Gao
Chen
C
Han
Jun
J
Dong
Xiao-Ping
XP
D000818:Animals; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D009249:NADP / Q000378:metabolism; D009711:Nucleotides / Q000494:pharmacology*; D010084:Oxidation-Reduction; D018620:PrPSc Proteins / Q000096:biosynthesis*; D011725:Pyridines / Q000494:pharmacology*
D009711:Nucleotides; D018620:PrPSc Proteins; D011725:Pyridines; D009249:NADP