NR AVLQ
AU Qin,K.; Zhao,L.; Tang,Y.; Bhatta,S.; Simard,J.M.; Zhao,R.Y.
TI Doppel-induced apoptosis and counteraction by cellular prion protein in neuroblastoma and astrocytes
QU Neuroscience 2006 Sep 1; 141(3): 1375-88
PT journal article
AB Expression of a prion-like protein, doppel, induces apoptosis-like changes in cerebellar neuronal granule and Purkinje cells of prion-knockout mice and this effect can be rescued by re-introduction of cellular prion. Since most of those studies were done in transgenic mice, in the present study, we have established a murine neuro-2a cell line and the primary rat adult reactive astrocyte model for studying doppel-induced apoptosis and possible prion counteraction. We demonstrate that expression of doppel in neuro-2a cells causes apoptosis, during which DNA fragmentation occurs as visualized by terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling staining and other intracellular changes characteristic of apoptosis are observed in the electron microscope. Using immunoblot analyses, we further demonstrate that doppel expression activates caspase-10 as well as caspase-3, but does not activate caspase-9. Addition of purified doppel to cultures of neuro-2a cells and the primary astrocytes causes similar apoptotic changes. Significantly, apoptosis induced by doppel is enhanced when cellular prion protein is depleted by RNA interference, suggesting a protective effect of cellular prion against doppel-induced apoptosis. The antagonistic interaction between cellular prion and doppel appears to involve direct protein-protein interaction possibly on cell membrane as cellular prion and doppel physically interact with each other and co-localize on cell membranes. Together, our data show that doppel induces apoptosis in neuroblastoma neuro-2a and rat primary astrocytes via a caspase-10 mediated pathway and that this effect is counteracted by cellular prion through direct interaction with doppel possibly on cell membrane.
MH Animals; Apoptosis/*drug effects; Astrocytes/*drug effects/ultrastructure; Blotting, Western/methods; Caspases/metabolism; Cells, Cultured; Comparative Study; Drug Interactions; Fluorescent Antibody Technique/methods; Gene Expression/drug effects/physiology; In Situ Nick-End Labeling/methods; Indoles/diagnostic use; Mice; Microscopy, Electron, Transmission/methods; Neuroblastoma/metabolism/*pathology/ultrastructure; Prions/metabolism/pharmacology/*physiology; RNA Interference/physiology; Rats; Research Support, Non-U.S. Gov't; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods; Time Factors; Transfection/methods
AD Department of Pathology, University of Maryland School of Medicine, 10 South Pine Street, MSTF 700A, Baltimore, MD 21201, USA
SP englisch
PO USA