Primary structure of the cAMP-dependent phosphorylation site of the plasma membrane calcium pump.
The primary structure of a region of the erythrocyte plasma membrane calcium pump which is phosphorylated by the cAMP-dependent protein kinase has been determined. The sequence is A-P-T-K-R-N-S-S(P)-P-P-P-S-P-D. The site is located between the calmodulin binding domain and the C-terminus of the ATPase. The ATPase is phosphorylated only at this site by the cAMP-dependent protein kinase, and the phosphorylation is inhibited by calmodulin. The effect of the phosphorylation is to decrease the Km for Ca2+ of the purified ATPase from about 10 microM to about 1.4 microM and to increase the Vmax of ATP hydrolysis about 2-fold.
James
P H
PH
Laboratory of Biochemistry, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland.
Pruschy
M
M
Vorherr
T E
TE
Penniston
J T
JT
Carafoli
E
E
D000595:Amino Acid Sequence; D001665:Binding Sites; D015220:Calcium Channels / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism*; D004910:Erythrocyte Membrane / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010766:Phosphorylation
D015220:Calcium Channels; D000242:Cyclic AMP