Microarray expression profiling identifies early signaling transcripts associated with 6-OHDA-induced dopaminergic cell death.
The parkinsonian mimetic 6-hydroxydopamine (6-OHDA) has been shown to cause transcriptional changes associated with cellular stress and the unfolded protein response. As these cellular sequelae depend on upstream signaling events, the present study used functional genomics and proteomic approaches to aid in deciphering toxin-mediated regulatory pathways. Microarray analysis of RNA collected from multiple time points following 6-OHDA treatment was combined with data mining and clustering techniques to identify distinct functional subgroups of genes. Notably, stress-induced transcription factors such as ATF3, ATF4, CHOP, and C/EBP beta were robustly up-regulated, yet exhibited unique kinetic patterns. Genes involved in the synthesis and modification of proteins (various tRNA synthetases), protein degradation (e.g., ubiquitin, Herpud1, Sqstm1), and oxidative stress (Hmox1, Por) could be subgrouped into distinct kinetic profiles as well. Realtime PCR and/or two-dimensional electrophoresis combined with western blotting validated data derived from microarray analyses. Taken together, these data support the notion that oxidative stress and protein dysfunction play a role in Parkinson's disease, as well as provide a time course for many of the molecular events associated with 6-OHDA neurotoxicity.
Holtz
William A
WA
Washington University School of Medicine, Anatomy and Neurobiology Department, St. Louis, MO 63110, USA.
Turetzky
Jay M
JM
O'Malley
Karen L
KL
D000818:Animals; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D016000:Cluster Analysis; D015180:Electrophoresis, Gel, Two-Dimensional; D020869:Gene Expression Profiling; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics / Q000378:metabolism; D051547:Heme Oxygenase-1; D007700:Kinetics; D008565:Membrane Proteins; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis; D018384:Oxidative Stress; D016627:Oxidopamine / Q000633:toxicity*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects* / Q000235:genetics*; D013997:Time Factors; D014158:Transcription, Genetic / Q000235:genetics
D008565:Membrane Proteins; D012333:RNA, Messenger; D016627:Oxidopamine; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1; C496542:Hmox1 protein, mouse