The Wilson's disease protein expressed in Sf9 cells is phosphorylated.
The Wilson's disease protein (WNDP), a copper transporter, is a crucial mediator of copper homoeostasis in mammalian cells. We recently found that changes in copper concentration regulate the phosphorylation level of WNDP. WNDP phosphorylation was observed in several mammalian cell lines, suggesting that a common phosphorylation pathway exists in these cells. Here we demonstrate that WNDP expressed in Sf9 insect cells is also phosphorylated, as evidenced by metabolic labelling of these cells with [(32)P]P(i). Because the baculovirus system allows us to generate large amounts of protein, we are using this expression method to isolate WNDP and map the sites of WNDP phosphorylation. The identification of phosphorylation sites is the first step towards understanding the physiological role of WNDP phosphorylation.
Vanderwerf
S M
SM
Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97201, USA.
Lutsenko
S
S
D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D027682:Cation Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003300:Copper / Q000378:metabolism*; D000073840:Copper-Transporting ATPases; D006801:Humans; D008958:Models, Molecular; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D018411:Spodoptera; D014162:Transfection
D027682:Cation Transport Proteins; D010750:Phosphoproteins; D011994:Recombinant Proteins; D003300:Copper; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D000073840:Copper-Transporting ATPases