Identification, purification and characterization of a novel phosphatidylinositol-specific phospholipase C, a third member of the beta subfamily.
The partial sequence of a novel PtdIns-specific phospholipase C of the beta subfamily (PtdIns-PLC beta 3) is described. Based upon the predicted protein sequence, monospecific antibodies have been raised and used to identify a suitable source for purification of the protein. Fractionation of HeLa S3 cells revealed that immunoreactive PtdIns-PLC beta 3 is membrane associated; purification (approximately 1000-fold) from this fraction yielded a single immunoreactive protein of 158 kDa, with a specific activity of 136 mumol.min-1.mg-1, with PtdIns 4,5-bisphosphate as substrate. Substrate specificity and Ca2+ dependence of this purified PtdIns-PLC are characteristic of the PtdIns-PLC beta subfamily.
Carozzi
A J
AJ
Imperial Cancer Research Fund, Lincoln's Inn Fields, London, England.
Kriz
R W
RW
Webster
C
C
Parker
P J
PJ
D000595:Amino Acid Sequence; D001483:Base Sequence; D002118:Calcium / Q000494:pharmacology; D002460:Cell Line; D004247:DNA / Q000737:chemistry / Q000302:isolation & purification; D005347:Fibroblasts / Q000201:enzymology; D006367:HeLa Cells / Q000201:enzymology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D054801:Phosphoinositide Phospholipase C; D010727:Phosphoric Diester Hydrolases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D013379:Substrate Specificity
D004247:DNA; D010727:Phosphoric Diester Hydrolases; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D002118:Calcium