Role for Rab10 in Methamphetamine-Induced Behavior.
Lipid rafts are specialized, cholesterol-rich membrane compartments that help to organize transmembrane signaling by restricting or promoting interactions with subsets of the cellular proteome. The hypothesis driving this study was that identifying proteins whose relative abundance in rafts is altered by the abused psychostimulant methamphetamine would contribute to fully describing the pathways involved in acute and chronic effects of the drug. Using a detergent-free method for preparing rafts from rat brain striatal membranes, we identified density gradient fractions enriched in the raft protein flotillin but deficient in calnexin and the transferrin receptor, markers of non-raft membranes. Dopamine D1- and D2-like receptor binding activity was highly enriched in the raft fractions, but pretreating rats with methamphetamine (2 mg/kg) once or repeatedly for 11 days did not alter the distribution of the receptors. LC-MS analysis of the protein composition of raft fractions from rats treated once with methamphetamine or saline identified methamphetamine-induced changes in the relative abundance of 23 raft proteins, including the monomeric GTP-binding protein Rab10, whose abundance in rafts was decreased 2.1-fold by acute methamphetamine treatment. Decreased raft localization was associated with a selective decrease in the abundance of Rab10 in a membrane fraction that includes synaptic vesicles and endosomes. Inhibiting Rab10 activity by pan-neuronal expression of a dominant-negative Rab10 mutant in Drosophila melanogaster decreased methamphetamine-induced activity and mortality and decreased caffeine-stimulated activity but not mortality, whereas inhibiting Rab10 activity selectively in cholinergic neurons had no effect. These results suggest that activation and redistribution of Rab10 is critical for some of the behavioral effects of psychostimulants.
Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, United States of America; Department of Integrative Biosciences, Oregon Health & Science University, Portland, Oregon, United States of America.
Scott M
SM
Vanderwerf
Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, United States of America.
David C
DC
Buck
Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon, United States of America.
Phillip A
PA
Wilmarth
Department of Integrative Biosciences, Oregon Health & Science University, Portland, Oregon, United States of America.
Leila M
LM
Sears
Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon, United States of America.
Larry L
LL
David
Department of Integrative Biosciences, Oregon Health & Science University, Portland, Oregon, United States of America.
David B
DB
Morton
Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, United States of America; Research Service, VA Portland Health Care System, Portland, Oregon, United States of America.
Kim A
KA
Neve
D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology*; D029721:Drosophila Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D008297:Male; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism; D008694:Methamphetamine / Q000494:pharmacology*; D020559:Monomeric GTP-Binding Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D017207:Rats, Sprague-Dawley; D011954:Receptors, Dopamine / Q000032:analysis / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000032:analysis / Q000378:metabolism*
D018765:Dopamine Uptake Inhibitors; D029721:Drosophila Proteins; C082378:Rab10 protein, rat; D011954:Receptors, Dopamine; D008694:Methamphetamine; D020559:Monomeric GTP-Binding Proteins; C579344:Rab10 protein, Drosophila; D020691:rab GTP-Binding Proteins