CD36 forms covalently associated dimers and multimers in platelets and transfected COS-7 cells.
CD36 is a transmembrane glycoprotein expressed on the surface of a number of cell types. The analysis of CD36 from platelets using immunoblotting, gel filtration, and native PAGE indicated the presence of high molecular complexes exceeding the Mr of monomeric CD36. Experiments using transfected COS-7 cells revealed these complexes were homodimers and -multimers of CD36. The multimers could be dissociated by treatment with a reducing agent, indicating they were formed by intermolecular cysteine-bridging. Mutagenesis of the cDNA for CD36 implicated the cysteines in the extracellular domain of the molecule. The potential physiological roles of CD36 multimerisation are discussed.
Thorne
R F
RF
Cancer Research Unit, Faculty of Medicine and Health Sciences, University of Newcastle, NSW, Australia. rthorne@mail.newcastle.edu.au
Meldrum
C J
CJ
Harris
S J
SJ
Dorahy
D J
DJ
Shafren
D R
DR
Berndt
M C
MC
Burns
G F
GF
Gibson
P G
PG
D000818:Animals; D001704:Biopolymers; D001792:Blood Platelets / Q000737:chemistry*; D018955:CD36 Antigens / Q000097:blood / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D019556:COS Cells; D002850:Chromatography, Gel; D003545:Cysteine / Q000737:chemistry / Q000378:metabolism; D019281:Dimerization; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D015151:Immunoblotting; D008856:Microscopy, Fluorescence; D016296:Mutagenesis; D011487:Protein Conformation; D013438:Sulfhydryl Compounds / Q000494:pharmacology; D013462:Sulfur Radioisotopes; D014162:Transfection
D001704:Biopolymers; D018955:CD36 Antigens; D013438:Sulfhydryl Compounds; D013462:Sulfur Radioisotopes; D003545:Cysteine