45K actin filament-severing protein from sea urchin eggs: interaction with phosphatidylinositol-4,5-bisphosphate.
An actin filament-severing activity of 45K protein isolated from sea urchin eggs was abolished when this protein was incubated with phosphatidylinositol-4,5-bisphosphate (PIP2). This effect was specific to PIP2 since phosphatidylinositol, phosphatidylinositol-4-monophosphate, inositol-1,4,5-trisphosphate, and phosphatidylserine did not show such an effect at the same concentration. Digestion of PIP2 with phospholipase C eliminated the effect. On the other hand, PIP2 did not affect either the formation of 45K protein-actin complex or actin filament-capping activity of the complex. Possible implication of the binding of PIP2 to 45K protein in cytoskeleton formation after fertilization of sea urchin eggs is discussed.
Ohnuma
M
M
Department of Biology, College of Arts and Sciences, University of Tokyo.
Mabuchi
I
I
D000199:Actins / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D003598:Cytoskeletal Proteins; D008970:Molecular Weight; D010447:Peptide Hydrolases; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism / Q000494:pharmacology; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism / Q000494:pharmacology*; D012617:Sea Urchins; D010738:Type C Phospholipases / Q000378:metabolism
D000199:Actins; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D018129:Phosphatidylinositol Phosphates; C060974:phosphatidylinositol 3,4,5-triphosphate; C037178:phosphatidylinositol 4-phosphate; C042641:su-45 protein, Hemicentrotus pulcherrimus; D017853:Phosphotransferases (Alcohol Group Acceptor); C068961:phosphatidylinositol 4,5-biphosphate kinase; D010738:Type C Phospholipases; D010447:Peptide Hydrolases