Identification and purification of a novel receptor for secretory phospholipase A(2) in porcine cerebral cortex

A specific phospholipase A(2) receptor from porcine cerebral cortex has been characterized (K(d) = 145 nM, B(max) = 0.4 pmol/mg membrane protein) by using a radioiodinated derivative of ammodytoxin C (AtxC), a snake venom presynaptically neurotoxic group IIA phospholipase A(2). After the receptor wa...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of biological chemistry 1999-09, Vol.274 (37), p.26315
Main Authors: Copic, A, Vucemilo, N, Gubensek, F, Krizaj, I
Format: Article
Language:English
Subjects:
Animals
Cerebral Cortex - metabolism
Chromatography, Affinity
Electrophoresis, Polyacrylamide Gel
Group II Phospholipases A2
Membrane Proteins - isolation & purification
Membrane Proteins - metabolism
Phospholipases A - metabolism
Swine
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A specific phospholipase A(2) receptor from porcine cerebral cortex has been characterized (K(d) = 145 nM, B(max) = 0.4 pmol/mg membrane protein) by using a radioiodinated derivative of ammodytoxin C (AtxC), a snake venom presynaptically neurotoxic group IIA phospholipase A(2). After the receptor was solubilized in a ligand-binding form, it was approximately 14,000-fold enriched by chromatography on wheat germ lectin-Sepharose and AtxC-Affi-Gel 10. The receptor is a single chain glycoprotein with an apparent molecular mass of 180 kDa and binds toxic and non-toxic phospholipases A(2) of either group I or II. It also recognizes conjugates of bovine serum albumin with mannose, N-acetylglucosamine, and galactose. In its molecular mass and pharmacological profile, the AtxC receptor resembles the M-type receptor for secretory phospholipases A(2) from rabbit skeletal muscle (a C-type multilectin, homologous to macrophage mannose receptor), yet in terms of relative abundance in brain and antigenicity, these two receptors are completely different. A further AtxC receptor of approximately 200 kDa discovered in porcine liver was, however, recognized by anti-rabbit M-type phospholipase A(2) receptor antibodies. There are, therefore, two immunologically distinct secretory phospholipase A(2) receptors of about 200 kDa in the same species. Although the liver receptor is related to the M-type secretory phospholipase A(2) receptors, the brain receptor is not and belongs to a novel group of secretory phospholipase A(2) receptors.
ISSN:0021-9258
DOI:10.1074/jbc.274.37.26315