Sites on phospholipase D2 phosphorylated by PKCalpha.
The phosphorylation sites in phospholipase D2 (PLD2) induced by activation of protein kinase Calpha (PKCalpha) in COS 7 cells were analyzed by mass spectrometry. Ser134, 146, and 243, and Thr72, 99/100, and 252 were identified. These sites were mutated to Ala and the double mutation of Ser243 and Thr252 eliminated the phosphorylation. However, the PLD2 activity, and the binding between PKCalpha and PLD2 were unaffected by the mutations. We conclude that phosphorylation of these residues is not required for PLD2 activation by PKCalpha, and that protein-protein interaction between PLD2 and PKCalpha is sufficient to activate PLD2.
Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
Jun-Song
JS
Chen
John H
JH
Exton
D019943:Amino Acid Substitution; D000818:Animals; D001665:Binding Sites; D019556:COS Cells; D002522:Chlorocebus aethiops; D016297:Mutagenesis, Site-Directed; D010739:Phospholipase D / Q000737:chemistry* / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D011493:Protein Kinase C / Q000737:chemistry* / Q000378:metabolism*; D051571:Protein Kinase C-alpha; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism
D011994:Recombinant Proteins; D011493:Protein Kinase C; D051571:Protein Kinase C-alpha; C105606:phospholipase D2; D010739:Phospholipase D