二酰基甘油刺激公羊精子的钙依赖性磷脂酶A2。

Diacylglycerol stimulates the Ca2(+)-dependent phospholipase A2 of ram spermatozoa.

作者信息

Roldan E R, Mollinedo F

机构信息

Department of Molecular Embryology, AFRC Institute of Animal Physiology and Genetics Research, Babraham, Cambridge, U.K.

出版信息

Biochem Biophys Res Commun. 1991 Apr 15;176(1):294-300. doi: 10.1016/0006-291x(91)90923-u.

DOI:10.1016/0006-291x(91)90923-u

PMID:2018523

Abstract

We have investigated phospholipase A2 (PLA2) activity in sonicates from ram spermatozoa and have analyzed the enzyme's susceptibility both to various inhibitors and to stimulation by diacylglycerols (DAGs). Ram sperm PLA2 activity was Ca2(+)-dependent and was inhibited by dexamethasone, chloracysine and compounds Ro 31-4493 and Ro 31-4639; mepacrine, however, did not inhibit PLA2 activity. Addition of three different 1,2-DAGs (dioctanoyl-sn-glycerol, oleoyl-acetyl-sn-glycerol and dioleoyl-sn-glycerol) markedly increased PLA2 activity; moreover, both 1,2- and 1,3-isomers enhanced enzyme activity. Since ram spermatozoa lack active protein kinase C, the target of DAG in most cells, our results suggest that stimulation of PLA2 activity by DAG may play an important role in intracellular signalling in the sperm cell.

摘要

我们研究了公羊精子超声裂解物中的磷脂酶A2（PLA2）活性，并分析了该酶对各种抑制剂以及二酰基甘油（DAGs）刺激的敏感性。公羊精子PLA2活性依赖于Ca2+，并受到地塞米松、氯噻嗪以及化合物Ro 31-4493和Ro 31-4639的抑制；然而，米帕林并不抑制PLA2活性。添加三种不同的1,2-二酰基甘油（二辛酰-sn-甘油、油酰-乙酰-sn-甘油和二油酰-sn-甘油）可显著提高PLA2活性；此外，1,2-异构体和1,3-异构体均增强了酶活性。由于公羊精子缺乏活性蛋白激酶C（大多数细胞中DAG的靶点），我们的结果表明，DAG对PLA2活性的刺激可能在精子细胞的细胞内信号传导中起重要作用。