Premium
Two phases of inositol polyphosphate and diacylglycerol production at fertilisation
Author(s) -
Ciapa Brigitte,
Whitaker Michael
Publication year - 1986
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(86)80191-0
Subject(s) - diacylglycerol kinase , inositol , phosphatidylinositol , exocytosis , antiporter , calcium , second messenger system , inositol trisphosphate , chemistry , fertilisation , biochemistry , phosphatidylinositol 4,5 bisphosphate , biology , protein kinase c , intracellular , kinase , secretion , receptor , organic chemistry , membrane , embryogenesis , gene , reproductive technology
[ 3 H]Inositol and [ 3 H]arachidonic acid were used to label polyphosphoinositide phospholipids in sea urchin eggs. Both [ 3 H]inositol polyphosphate (InsP 3 ) and [ 3 H]diacylglycerol (DAG) increase at fertilisation. An early increase in InsP 3 occurs as the sperm‐induced calcium transient crosses the egg and exocytosis occurs; a later increase in InsP 3 , as calcium declines and the protein kinase C‐dependent Na/H antiporter causes the cytoplasmic pH to increase. These results support suggestions that a calcium‐induced hydrolysis of phosphatidylinositol bisphosphate occurs at fertilisation, that the production of diacylglycerol may be essential for exocytosis and that diacylglycerol production at fertilisation stimulates the Na/H antiporter. The increase in [ 3 H]inositol polyphosphate as calcium declines indicates that this second messenger may have some function later in the cell cycle.