Purification and partial characterisation of an alpha-tocopherol-binding protein from rabbit heart cytosol.
An alpha-tocopherol-binding protein has been isolated and purified from rabbit heart cytosol. The purified protein had an apparent molecular mass of 14,200, as derived from SDS-PAGE. The content of the protein in rabbit heart was around 11.8 micrograms per g of tissue. The binding of alpha-tocopherol to the purified protein was rapid, reversible, and saturable. Neither gamma nor delta tocopherol could displace the bound alpha-tocopherol from the protein, suggesting a high specificity for alpha-tocopherol. alpha-Tocopherol-binding protein did not bind oleate. Transfer of alpha-tocopherol from liposomes to mitochondria was stimulated 8-fold in the presence of the binding protein, suggesting that this protein may be involved in the intracellular transport of alpha-tocopherol in the heart.
Dutta-Roy
A K
AK
Division of Biochemical Sciences, Rowett Research Institute, Aberdeen, Scotland, UK.
Gordon
M J
MJ
Leishman
D J
DJ
Paterson
B J
BJ
Duthie
G G
GG
James
W P
WP
D000818:Animals; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005227:Fatty Acids / Q000378:metabolism; D008929:Mitochondria, Heart / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D011485:Protein Binding; D011817:Rabbits; D014810:Vitamin E / Q000378:metabolism*
D002352:Carrier Proteins; D005227:Fatty Acids; C017763:alpha-tocopherol transfer protein; D014810:Vitamin E