Enzymological analysis of the tumor suppressor A-C1 reveals a novel group of phospholipid-metabolizing enzymes

( Max 2000 Items )
URI http://shark.lib.kagawa-u.ac.jp/kuir/metadata/27472
Title
Enzymological analysis of the tumor suppressor A-C1 reveals a novel group of phospholipid-metabolizing enzymes
File
Description

Abstract

A-C1 protein is the product of a tumor suppressor gene negatively regulating the oncogene Ras and belongs to the HRASLS (HRAS-like suppressor) subfamily. We recently found that four members of this subfamily expressed in human tissues function as phospholipid-metabolizing enzymes. Here we examined a possible enzyme activity of A-C1. The homogenates of COS-7 cells overexpressing recombinant A-C1s from human, mouse, and rat showed a phospholipase A½ (PLA½) activity toward phosphatidylcholine (PC). This finding was confirmed with the purified A-C1. The activity was Ca²⁺ independent, and dithiothreitol and Nonidet P-40 were indispensable for full activity. Phosphatidylethanolamine (PE) was also a substrate and the phospholipase A₁ (PLA₁) activity was dominant over the PLA₂ activity. Furthermore, the protein exhibited acyltransferase activities transferring an acyl group of PCs to the amino group of PEs and the hydroxyl group of lyso PCs. As for tissue distribution in human, mouse, and rat, A-C1 mRNA was abundantly expressed in testis, skeletal muscle, brain, and heart. These results demonstrate that A-C1 is a novel phospholipid-metabolizing enzyme. Moreover, the fact that all five members of the HRASLS subfamily, including A-C1, show similar catalytic properties strongly suggests that these proteins constitute a new class of enzymes showing PLA½ and acyltransferase activities.

(医博甲589)

Author
著者 篠原 尚樹
著者(ヨミ) シノハラ ナオキ
著者(別表記) Shinohara Naoki
Publication Title
Journal of Lipid Research
Publication Title Alternative
J Lipid Res.
Volume
52
Issue
11
Start Page
1927
End Page
1935
Publisher
American Society for Biochemistry and Molecular Biology
Published Date
2011-08-31
ISSN
0022-2275
NCID
AA00701215
PMID
21880860
DOI
10.1194/jlr.M015081
Resource Type
Thesis or Dissertation
Language
eng
Relation
PMCID:PMC3196224
Resource URL
https://doi.org/10.1194/jlr.M015081
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3196224/
Text Version
none
Grant ID
博甲第589号
Grant Date
2014-03-24
Degree Name
博士(医学)
Grantor
香川大学
Set
香川大学
Copyright (C) 2009 Kagawa University All rights reserved.