Prion protein gene polymorphisms in Turkish native goat breeds
JOURNAL OF GENETICS
Authors: Meydan, Hasan; Pehlivan, Erkan; Ozkan, Mustafa Muhip; Yildiz, Mehmet Ali; Goldmann, Wilfred
Abstract
Susceptibility to 'scrapie' disease in goats is influenced by polymorphisms of the prion protein (PRNP) gene. The aim of this study was to identify PRNP gene polymorphisms in a total of 356 scrapie disease-free goats from 10 Turkish native breeds. Eighteen single-nucleotide polymorphisms were detected in the caprine PRNP open-reading frame. Ten previously described amino acid substitutions (I142M, H143R, N146S, N146D, R151H, R154H, P168Q, R211Q, Q222K and P240S) and two novel dimorphisms (G134E and Q163P) were identified. The strongest association between caprine PRNP and relative resistance to scrapie disease has been reported previously for polymorphisms at codons 146 (S /D) and 222 (K). In the present study, these three PrP variants were relatively rare with 6.3%. This is the first report on PRNP gene variation in Turkish native goat breeds and our knowledge of these polymorphisms will assist goat breeding programmes to reduce the risk of scrapie.
Impairment of cerebellar long-term depression and GABAergic transmission in prion protein deficient mice ectopically expressing PrPLP/Dpl
SCIENTIFIC REPORTS
Authors: Kishimoto, Yasushi; Hirono, Moritoshi; Atarashi, Ryuichiro; Sakaguchi, Suehiro; Yoshioka, Tohru; Katamine, Shigeru; Kirino, Yutaka
Abstract
Prion protein (PrPC) knockout mice, named as the "Ngsk" strain (Ngsk Prnp(0/0) mice), show late-onset cerebellar Purkinje cell (PC) degeneration because of ectopic overexpression of PrPC-like protein (PrPLP/Dpl). Our previous study indicated that the mutant mice also exhibited alterations in cerebellum-dependent delay eyeblink conditioning, even at a young age (16 weeks of age) when neurological changes had not occurred. Thus, this electrophysiological study was designed to examine the synaptic function of the cerebellar cortex in juvenile Ngsk Prnp(0/0) mice. We showed that Ngsk Prnp(0/0) mice exhibited normal paired-pulse facilitation but impaired long-term depression of excitatory synaptic transmission at synapses between parallel fibres and PCs. GABA(A)-mediated inhibitory postsynaptic currents recorded from PCs were also weakened in Ngsk Prnp(0/0) mice. Furthermore, we confirmed that Ngsk Prnp(0/0) mice (7-8-week-old) exhibited abnormalities in delay eyeblink conditioning. Our findings suggest that these alterations in both excitatory and inhibitory synaptic transmission to PCs caused deficits in delay eyeblink conditioning of Ngsk Prnp(0/0) mice. Therefore, the Ngsk Prnp(0/0) mouse model can contribute to study underlying mechanisms for impairments of synaptic transmission and neural plasticity, and cognitive deficits in the central nervous system.