Identity of inositol 1,2-cyclic phosphate 2-phosphohydrolase with lipocortin III.
The amino acid sequences of three fragments of cyanogen bromide-digested human placental inositol 1,2-cyclic phosphate 2-phosphohydrolase, an enzyme of the phosphatidylinositol signaling pathway, are identical to sequences within lipocortin III, a member of a family of homologous calcium- and phospholipid-binding proteins that do not have defined physiological functions. Lipocortin III has also been previously identified as placental anticoagulant protein III (PAP III) and calcimedin 35 alpha. Antibodies to PAP III detected PAP III and inositol 1,2-cyclic phosphate 2-phosphohydrolase with identical reactivity on immunoblotting. In addition, inositol 1,2-cyclic phosphate 2-phosphohydrolase was stimulated by the same acidic phospholipids that bind lipocortins.
Ross
T S
TS
Department of Internal Medicine, Washington University School of Medicine, St Louis, MO 63110.
Tait
J F
JF
Majerus
P W
PW
D000595:Amino Acid Sequence; D017318:Annexin A3; D017302:Annexins; D002135:Calcium-Binding Proteins / Q000235:genetics*; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007700:Kinetics; D008969:Molecular Sequence Data; D010727:Phosphoric Diester Hydrolases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy
D017302:Annexins; D002135:Calcium-Binding Proteins; D010727:Phosphoric Diester Hydrolases; D017318:Annexin A3