Brain region-specific N-glycosylation and lipid rafts association of the rat mu opioid receptor.
The mu opioid receptor (MOR) in the rat and mouse caudate putamen (CPu) and thalamus was demonstrated as diffuse and broad bands by Western blot with a polyclonal antibody against a C-terminal peptide of MOR, which were absent in the cerebellum and brains of MOR-knockout mice. The electrophoretic mobility of MOR differed in the two brain regions with median relative molecular masses (Mr's) of 75 kDa (CPu) vs. 66 kDa (thalamus) for the rat, and 74 kDa (CPu) vs. 63 kDa (thalamus) for the mouse, which was due to its differential N-glycosylation. Rat MOR in CPu was found mainly associated with low-density cholesterol- and ganglioside M1 (GM1)-enriched membrane subdomains (lipid rafts), while the MOR in the thalamus was present in rafts and non-rafts without preference. Cholesterol reduction by methyl-beta-cyclodextrin decreased DAGMO-induced [35S]GTPgammaS binding in rat CPu membranes to a greater extent than in the thalamus membranes.
Huang
Peng
P
Department of Pharmacology, Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA 19140, USA.
Chen
Chongguang
C
Xu
Wei
W
Yoon
Su-In
SI
Unterwald
Ellen M
EM
Pintar
John E
JE
Wang
Yulin
Y
Chong
Parkson Lee-Gau
PL
Liu-Chen
Lee-Yuan
LY
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002846:Chromatography, Affinity; D005260:Female; D006026:Glycoside Hydrolases / Q000378:metabolism; D006031:Glycosylation; D006801:Humans; D047468:Immunoprecipitation; D008297:Male; D021962:Membrane Microdomains / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D051381:Rats; D017207:Rats, Sprague-Dawley; D017450:Receptors, Opioid, mu / Q000235:genetics / Q000378:metabolism*; D047392:beta-Cyclodextrins / Q000494:pharmacology
C485765:Oprm1 protein, rat; D017450:Receptors, Opioid, mu; D047392:beta-Cyclodextrins; C108732:methyl-beta-cyclodextrin; D006026:Glycoside Hydrolases