Molecular identification of albumin and Hsp70 as cytosolic anandamide-binding proteins.
The cellular uptake and the intracellular synthesis/degradation of anandamide are crucial steps for controlling its extracellular level and the duration of its activity. Although the biosynthesis and breakdown of anandamide are well understood, little is known about the mechanisms underlying its intracellular transport. Here, we investigated the presence of a potential carrier-mediated trafficking of anandamide within the cytosol, using a biotinylated analog as a tool to catch by affinity chromatography anandamide-interacting proteins. The identity of two of these anandamide-binding proteins, Hsp70 and serum albumin, was determined by mass spectrometry, confirmed by western blotting and confocal microscopy, and further validated through an anandamide-binding assay. These findings suggest that the trafficking of anandamide from the plasma membrane to the internal compartments of a cell occur via a nonvesicular mechanism mediated by cytosolic carriers.
Oddi
Sergio
S
Department of Biomedical Sciences, University of Teramo, Teramo 64100, Italy.
Fezza
Filomena
F
Pasquariello
Nicoletta
N
D'Agostino
Antonella
A
Catanzaro
Giuseppina
G
De Simone
Chiara
C
Rapino
Cinzia
C
Finazzi-Agrò
Alessandro
A
Maccarrone
Mauro
M
D000418:Albumins / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001095:Arachidonic Acids / Q000737:chemistry / Q000378:metabolism*; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism*; D045744:Cell Line, Tumor; D003600:Cytosol / Q000378:metabolism*; D063388:Endocannabinoids; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D051379:Mice; D053284:Polyunsaturated Alkamides / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding
D000418:Albumins; D001095:Arachidonic Acids; D002352:Carrier Proteins; D063388:Endocannabinoids; D018840:HSP70 Heat-Shock Proteins; D053284:Polyunsaturated Alkamides; C078814:anandamide