The cellular prion protein colocalizes with the dystroglycan complex in the brain.
The function of PrP(C), the cellular prion protein (PrP), is still unknown. Like other glycophosphatidylinositol-anchored proteins, PrP resides on Triton-insoluble, cholesterol-rich membranous microdomains, termed rafts. We have recently shown that the activity and subcellular localization of the neuronal isoform of nitric oxide synthase (nNOS) are impaired in adult PrP(0/0) mice as well as in scrapie-infected mice. In this study, we sought to determine whether PrP and nNOS are part of the same functional complex and, if so, to identify additional components of such a complex. To this aim, we looked for proteins that coimmunoprecipitated with PrP in the presence of detergents either that completely dissociate rafts, to identify stronger interactions, or that preserve the raft structure, to identify weaker interactions. Using this detergent-dependent immunoprecipitation protocol we found that PrP interacts strongly with dystroglycan, a transmembrane protein that is the core of the dystrophin-glycoprotein complex (DGC). Additional results suggest that PrP also interacts with additional members of the DGC, including nNOS. PrP coprecipitated only with established presynaptic proteins, consistent with recent findings suggesting that PrP is a presynaptic protein.
Keshet
G I
GI
Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, Hadassah Hebrew University Hospital, Jerusalem, Israel.
Bar-Peled
O
O
Yaffe
D
D
Nudel
U
U
Gabizon
R
R
D000199:Actins / Q000378:metabolism; D000818:Animals; D000936:Antigen-Antibody Complex / Q000737:chemistry; D001921:Brain / Q000378:metabolism*; D002458:Cell Fractionation; D002531:Cerebellum / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D003902:Detergents / Q000737:chemistry; D049030:Dystroglycans; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D046911:Macromolecular Substances; D008562:Membrane Glycoproteins / Q000378:metabolism*; D021962:Membrane Microdomains / Q000737:chemistry; D051379:Mice; D009419:Nerve Tissue Proteins / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I; D017830:Octoxynol; D011092:Polyethylene Glycols / Q000737:chemistry; D018621:PrPC Proteins / Q000378:metabolism*; D011233:Precipitin Tests; D016708:Synaptophysin / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism
D000199:Actins; D000936:Antigen-Antibody Complex; D003598:Cytoskeletal Proteins; D003902:Detergents; D017261:Glycosylphosphatidylinositols; D046911:Macromolecular Substances; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D018621:PrPC Proteins; D016708:Synaptophysin; D014404:Tubulin; C033652:postsynaptic density proteins; D049030:Dystroglycans; D011092:Polyethylene Glycols; D017830:Octoxynol; C010615:Nonidet P-40; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; C496321:Nos1 protein, mouse