title: CD147, a gamma-secretase associated protein is upregulated in Alzheimer's disease brain and its cellular trafficking is affected by presenilin-2.
abstract: Gamma-secretase activity has been extensively investigated due to its role in Alzheimer's disease. Here, we studied the association of CD147, a transmembrane glycoprotein belonging to the immunoglobulin family, with gamma-secretase and its expression in Alzheimer's disease and control tissues. Subcellular fractionation of postmitochondrial supernatant from rat brain on step iodixanol gradient in combination with co-immunoprecipitation using an anti-nicastrin antibody showed association of limited amount of CD147 to gamma-secretase. By immunoblotting of postnuclear pellets from Alzheimer's disease and control human brain tissues we showed that CD147 with molecular weight 75 kDa is upregulated in frontal cortex and thalamus of the Alzheimer's disease brains. Immunohistochemistry of brain tissues from Alzheimer's disease and control revealed specific upregulation of CD147 in neurons, axons and capillaries of Alzheimer's disease frontal cortex and thalamus. The effect of presenilin-1 and -2, which are the catalytic subunits of gamma-secretase, on CD147 expression and subcellular localization was analyzed by confocal microscopy in combination with flow cytometry and showed that PS2 affected the subcellular localization of CD147 in mouse embryonic fibroblast cells. We suggest that a small fraction of CD147 present in the brain is associated with the gamma-secretase, and can be involved in mechanisms dysregulated in Alzheimer's disease brain.
authors.affiliation: KASPAC (Karolinska Institutet Dainippon Sumitomo Pharma Alzheimer Center), Huddinge, Sweden.
authors.forename: Jarmila
authors.initials: J
authors.lastname: Nahalkova
authors.forename: Inga
authors.initials: I
authors.lastname: Volkmann
authors.forename: Mikio
authors.initials: M
authors.lastname: Aoki
authors.forename: Bengt
authors.initials: B
authors.lastname: Winblad
authors.forename: Nenad
authors.initials: N
authors.lastname: Bogdanovic
authors.forename: Lars O
authors.initials: LO
authors.lastname: Tjernberg
authors.forename: Homira
authors.initials: H
authors.lastname: Behbahani
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism* / Q000503:physiopathology; D053829:Amyloid Precursor Protein Secretases / Q000378:metabolism*; D000818:Animals; D051926:Basigin / Q000378:metabolism*; D001921:Brain / Q000378:metabolism* / Q000503:physiopathology; D002451:Cell Compartmentation / Q000502:physiology; D042783:Endothelial Cells / Q000378:metabolism; D005260:Female; D005625:Frontal Lobe / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008297:Male; D051379:Mice; D009474:Neurons / Q000378:metabolism; D053766:Presenilin-2 / Q000378:metabolism*; D021381:Protein Transport / Q000502:physiology; D051381:Rats; D013347:Subcellular Fractions / Q000378:metabolism; D013788:Thalamus / Q000378:metabolism; D015854:Up-Regulation / Q000502:physiology
chemical_list: C497886:BSG protein, human; C508861:PSEN2 protein, human; D053766:Presenilin-2; D051926:Basigin; D053829:Amyloid Precursor Protein Secretases