Disruption of Doppel prevents neurodegeneration in mice with extensive Prnp deletions.
The Prnp gene encodes the cellular prion protein PrP(C). Removal of its ORF does not result in pathological phenotypes, but deletions extending into the upstream intron result in cerebellar degeneration, possibly because of ectopic cis-activation of the Prnd locus that encodes the PrP(C) homologue Doppel (Dpl). To test this hypothesis, we removed Prnd from Prnp(o/o) mice by transallelic meiotic recombination. Balanced loxP-mediated ablation yielded mice lacking both PrP(C) and Dpl (Prn(o/o)), which developed normally and showed unimpaired immune functions but suffered from male infertility. However, removal of the Prnd locus abolished cerebellar degeneration, proving that this phenotype is caused by Dpl upregulation. The absence of compound pathological phenotypes in Prn(o/o) mice suggests the existence of alternative compensatory mechanisms. Alternatively, Dpl and PrP(C) may exert distinct functions despite having partly overlapping expression profiles.
Genoud
Nicolas
N
Institute of Neuropathology, University Hospital Zürich, Schmelzbergstrasse 12, CH-8091 Zürich, Switzerland.
Behrens
Axel
A
Miele
Gino
G
Robay
Dimitri
D
Heppner
Frank L
FL
Freigang
Stefan
S
Aguzzi
Adriano
A
D000682:Amyloid / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D002524:Cerebellar Ataxia / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002531:Cerebellum / Q000473:pathology; D058851:GPI-Linked Proteins; D007107:Immune System / Q000276:immunology; D007248:Infertility, Male / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D019636:Neurodegenerative Diseases / Q000235:genetics* / Q000378:metabolism; D000072002:Prion Proteins; D011328:Prions / Q000235:genetics* / Q000378:metabolism; D011498:Protein Precursors / Q000235:genetics* / Q000378:metabolism; D017384:Sequence Deletion; D013997:Time Factors
D000682:Amyloid; D058851:GPI-Linked Proteins; D000072002:Prion Proteins; D011328:Prions; C122036:Prnd protein, mouse; C512657:Prnp protein, mouse; D011498:Protein Precursors