title: Overexpression of the Hspa13 (Stch) gene reduces prion disease incubation time in mice.
abstract: Prion diseases are fatal neurodegenerative disorders that include bovine spongiform encephalopathy (BSE) and scrapie in animals and Creutzfeldt-Jakob disease (CJD) in humans. They are characterized by long incubation periods, variation in which is determined by many factors including genetic background. In some cases it is possible that incubation time may be directly correlated to the level of gene expression. To test this hypothesis, we combined incubation time data from five different inbred lines of mice with quantitative gene expression profiling in normal brains and identified five genes with expression levels that correlate with incubation time. One of these genes, Hspa13 (Stch), is a member of the Hsp70 family of ATPase heat shock proteins, which have been previously implicated in prion propagation. To test whether Hspa13 plays a causal role in determining the incubation period, we tested two overexpressing mouse models. The Tc1 human chromosome 21 (Hsa21) transchromosomic mouse model of Down syndrome is trisomic for many Hsa21 genes including Hspa13 and following Chandler/Rocky Mountain Laboratory (RML) prion inoculation, shows a 4% reduction in incubation time. Furthermore, a transgenic model with eightfold overexpression of mouse Hspa13 exhibited highly significant reductions in incubation time of 16, 15, and 7% following infection with Chandler/RML, ME7, and MRC2 prion strains, respectively. These data further implicate Hsp70-like molecular chaperones in protein misfolding disorders such as prion disease.
authors.affiliation: Medical Research Council (MRC) Prion Unit, University College London (UCL) Institute of Neurology, London, United Kingdom.
authors.forename: Julia
authors.initials: J
authors.lastname: Grizenkova
authors.forename: Shaheen
authors.initials: S
authors.lastname: Akhtar
authors.forename: Holger
authors.initials: H
authors.lastname: Hummerich
authors.forename: Andrew
authors.initials: A
authors.lastname: Tomlinson
authors.forename: Emmanuel A
authors.initials: EA
authors.lastname: Asante
authors.forename: Adam
authors.initials: A
authors.lastname: Wenborn
authors.forename: Jérémie
authors.initials: J
authors.lastname: Fizet
authors.forename: Mark
authors.initials: M
authors.lastname: Poulter
authors.forename: Frances K
authors.initials: FK
authors.lastname: Wiseman
authors.forename: Elizabeth M C
authors.initials: EM
authors.lastname: Fisher
authors.forename: Victor L J
authors.initials: VL
authors.lastname: Tybulewicz
authors.forename: Sebastian
authors.initials: S
authors.lastname: Brandner
authors.forename: John
authors.initials: J
authors.lastname: Collinge
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Lloyd
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry; D000818:Animals; D005786:Gene Expression Regulation; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology*; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008822:Mice, Transgenic; D008957:Models, Genetic; D009474:Neurons / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D017096:Prion Diseases / Q000235:genetics*; D011328:Prions / Q000378:metabolism; D018075:RNA, Complementary / Q000378:metabolism
chemical_list: D018840:HSP70 Heat-Shock Proteins; C484192:Hspa13 protein, mouse; D011328:Prions; D018075:RNA, Complementary; D000251:Adenosine Triphosphatases