Characterization of a heavy metal ion transporter in the lysosomal membrane.
Lysosomes are thought to play a role in various aspects of heavy metal metabolism. In the present study we demonstrate for the first time the presence of a heavy metal ion transport protein in the lysosomal membrane. Uptake of radioactive silver both in highly purified lysosomal membrane vesicles and in purified intact lysosomes showed the typical kinetics of a carrier-mediated process. This transport was stimulated by ATP hydrolysis, and showed specificity for Ag+, Cu2+, and Cd2+. All biochemical properties of this lysosomal metal ion transporter could classify it as a heavy metal transporting P-type ATPase. Long Evans Cinnamon (LEC) rats, an animal model for the copper transport disorder Wilson disease, showed normal lysosomal silver transport.
Havelaar
A C
AC
Department of Clinical Genetics, Erasmus University, Rotterdam, The Netherlands.
de Gast
I L
IL
Snijders
S
S
Beerens
C E
CE
Mancini
G M
GM
Verheijen
F W
FW
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002104:Cadmium / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism*; D002458:Cell Fractionation; D003300:Copper / Q000378:metabolism; D007425:Intracellular Membranes / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008247:Lysosomes / Q000378:metabolism*; D051381:Rats; D020318:Rats, Long-Evans; D017208:Rats, Wistar; D012265:Ribonucleotides / Q000494:pharmacology; D012834:Silver / Q000378:metabolism*; D013379:Substrate Specificity
D002352:Carrier Proteins; D012265:Ribonucleotides; D002104:Cadmium; D012834:Silver; D003300:Copper; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases