|
KMID : 0614019990150010281
|
|
Journal of Pharmaceutical Sciences (C.N.U.)
1999 Volume.15 No. 1 p.281 ~ p.288
|
|
|
Release of GPI-Anchored Zn^(2+)-Glycerophosphocholine Cholinephosphodiesterase as an Amphiphilic Form from Bovine Brain Membranes by Bee Venom Phospholipase A_2
|
|
Lee Ji-Yeon
Kim Mee-Ree
Sok Dai-Eun
|
|
|
Abstract
|
|
|
|
Enzymatic release of Zn^2+-glycerophosphocholine (GPC)cholinephosphodiestrase, as an amphiphilic form, from bovine brain membranes was examined. Of various membrane hydrolases, bee PLA_2 was the most effect in the release of the GPC cholimephosphodiesterase (amphiphilic form, 63-70%) from membrane. Compared to pancreatic PLA_2, bee PLA_2 was more efficient in the release of GPC cholinephosphodiesterase. In pH-dependent release of GPI-anchored phosphodiesterase, there was a similar pH -release profile between PLA_2-mediated release and spontaneous one, implying the involvement of membrane disruption in the PLA_2 action. The PLA_2-mediated release showed a limited time-dependence (unti1 45 min) and a limited dose dependence(up to 3 units/ml), characteristic of a receptor-type binging. An ionicbinding of PLA_2 action. In support of an interaction between PLA_2 and membrane glycoproteins, the PLA_2 action was found to be blocked by lectins, wheat germ agglutinin or concanavalin A. In combination, the PLA_2 mediated release was found to be enhanced synergistically by saponin, a cholosterol-complexing agent. Meanwhile, an additive interaction between PLA_2 and lysolecithin suggests that PLA2 action independent of lysolecithin. It is suggested that the binding of PAL_2 to specific sites of membranes, probably rich in GPI-anchored glycoproteins, may be related to the facilitated release of GPI-anchored proteins as amphiphilic from.
|
|
|
KEYWORD
|
|
|
GPI, PLA_2, glycerophosphocholine, phosphodiesterase, release
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|
|