Internalization and signal transduction of PrP(106-126) in neuronal cells.
Invasion of the nervous system and neuronal spread of infection are critical, but poorly understood steps in the pathogenesis of prion diseases. We have thus analyzed the internalization and signal transduction of the neurotoxic fragment of the prion protein PrP(106-126) in the rat neuroblastoma cell line B104 by fluorescence microscopy and quantification by ELISA and in primary neuronal cells from mice. Phospholipase D (PLD) is known to be an enzyme involved in the regulation of secretion, endocytosis and receptor signalling. We determined the PLD activity using a transphosphatidylation assay and could show that PLD is involved in PrP(106-126) internalization. The determination of receptor activity via quantification of ERK1/2 phosphorylation and cAMP level measurement verified the PrP(106-126)-induced signal transduction in B104 cells and primary neuronal cells. PrP(106-126)-induced a decrease in cAMP level in neuronal cells. These studies indicate the involvement of PLD in PrP(106-126)-endocytosis and mediated cellular signalling by an unidentified inhibitory G-protein-coupled receptor and may allow the development of therapeutic agents interfering with prion uptake and/or PLD function using PLD as a possible pharmaceutical target.
Brandenburg
Lars-Ove
LO
Department of Anatomy and Cell Biology, Medical Faculty, RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany; Department of Anatomy, University of Kiel, Germany. lbrandenburg@ukaachen.de
Lucius
Ralph
R
Tameh Abolfazl
Azami
A
Kipp
Markus
M
Wruck
Christoph J
CJ
Koch
Thomas
T
Beyer
Cordian
C
Pufe
Thomas
T
D000199:Actins / Q000235:genetics; D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods; D045744:Cell Line, Tumor; D000242:Cyclic AMP / Q000378:metabolism; D017931:DNA Primers; D004705:Endocytosis / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009447:Neuroblastoma / Q000503:physiopathology; D009474:Neurons / Q000166:cytology / Q000201:enzymology / Q000502:physiology*; D010446:Peptide Fragments / Q000378:metabolism*; D010739:Phospholipase D / Q000235:genetics; D010740:Phospholipases / Q000378:metabolism; D017096:Prion Diseases / Q000503:physiopathology; D011328:Prions / Q000378:metabolism*; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction
D000199:Actins; D017931:DNA Primers; D010446:Peptide Fragments; D011328:Prions; C082632:prion protein (106-126); D000242:Cyclic AMP; D010740:Phospholipases; C105606:phospholipase D2; D010739:Phospholipase D; C106801:phospholipase D1