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Functional characterization of novel human ARFGAP3
Author(s) -
Liu Xiaoqin,
Zhang Chenggang,
Xing Guichun,
Chen Qingtang,
He Fuchu
Publication year - 2001
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/s0014-5793(01)02134-2
Subject(s) - adp ribosylation factor , cytosol , microbiology and biotechnology , secretion , vesicular transport protein , gtpase , gtpase activating protein , phosphatidylinositol , ectopic expression , biology , intracellular , in vitro , secretory pathway , alkaline phosphatase , biochemistry , vesicle , g protein , signal transduction , endoplasmic reticulum , enzyme , golgi apparatus , membrane , gene
ADP ribosylation factors (ARFs) are critical in the vesicular trafficking pathway. ARF activity is controlled by GTPase‐activating proteins (GAPs). We have identified recently a novel tentative ARF GAP derived from human fetal liver, ARFGAP3 (originally named as ARFGAP1). In the present study, we demonstrated that ARFGAP3 had GAP activity in vitro and remarked that the GAP activity of ARFGAP3 was regulated by phospholipids, i.e. phosphatidylinositol 4,5‐diphosphate as agonist and phosphatidylcholine as antagonist. ARFGAP3 is a predominantly cytosolic protein, and concentrated in the perinuclear region. Its transient ectopic overexpression in cultured mammalian cells reduced the constitutive secretion of secreted alkaline phosphatase, indicating that ectopic overexpression of ARFGAP3 inhibits the early secretory pathway of proteins in vivo. These results demonstrated that ARFGAP3 is a novel GAP for ARF1 and might be involved in intracellular traffic of proteins and vesicular transport as predicted.