Regulation of AP-3 function by inositides. Identification of phosphatidylinositol 3,4,5-trisphosphate as a potent ligand

Weihua Hao, Zheng Tan, Kondury Prasad, K. Kishta Reddy, Jian Chen, Glenn D. Prestwich, J R Falck, Stephen B. Shears, Eileen M. Lafer

Research output: Contribution to journalArticle

95 Citations (Scopus)

Abstract

As part of the growing effort to understand the role inositol phosphates and inositol lipids play in the regulation of vesicle traffic within nerve terminals, we determined whether or not the synapse-specific clathrin assembly protein AP-3 can interact with inositol lipids. We found that soluble dioctanoyl-phosphatidylinositol 3,4,5-trisphosphate (DiC8PtdIns(3,4,5)P3) was only 7.5-fold weaker a ligand than D-myo-inositol hexakisphosphate in assays that measured the displacement of D-myo- [3H]inositol hexakisphosphate. In functional assays we found that both of these ligands inhibited clathrin assembly, but DiC8-PtdIns(3,4,5)P3 was more potent and exhibited a larger maximal effect. We also examined the structural features of DiCs-PtdIns(3,4,5)P3 that establish specificity. Dioctanoyl-phosphatidylinositol 3,4-bisphosphate, which does not have a 5- phosphate, and 4,5-O-bisphosphoryl-D-myo-inosityl 1-O-(1,2-O-diundecyl)-sn- 3-glycerylphosphate, which does not have a 3-phosphate, were, respectively, 2-fold and 4-fold less potent than DiC8-PtdIns(3,4,5)P3 as inhibitors of clathrin assembly. Deacylation of DiCs-PtdIns(3,4,5)P3 reduced its affinity for AP-3 almost 20-fold, and also dramatically lowered its ability to inhibit clathrin assembly. The deacylated products of the soluble derivatives of phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 4,5- bisphosphate were both not significant inhibitors of clathrin assembly. It therefore appears that the interactions of inositides with AP-3 should not be considered simply in terms of electrostatic effects of the highly charged phosphate groups. Ligand specificity appears also to be mediated by hydrophobic interactions with the fatty-acyl chains of the inositol lipids.

Original languageEnglish (US)
Pages (from-to)6393-6398
Number of pages6
JournalJournal of Biological Chemistry
Volume272
Issue number10
DOIs
StatePublished - Mar 7 1997

Fingerprint

Clathrin
Ligands
Inositol
Phytic Acid
Phosphates
Lipids
Assays
Vesicular Transport Adaptor Proteins
Inositol Phosphates
Phosphatidylinositols
Static Electricity
Hydrophobic and Hydrophilic Interactions
Synapses
Electrostatics
phosphatidylinositol 3,4,5-triphosphate
Derivatives
1,2-dioctanoylglycerol
phosphatidylinositol 3,4-diphosphate

ASJC Scopus subject areas

  • Biochemistry

Cite this

Regulation of AP-3 function by inositides. Identification of phosphatidylinositol 3,4,5-trisphosphate as a potent ligand. / Hao, Weihua; Tan, Zheng; Prasad, Kondury; Reddy, K. Kishta; Chen, Jian; Prestwich, Glenn D.; Falck, J R; Shears, Stephen B.; Lafer, Eileen M.

In: Journal of Biological Chemistry, Vol. 272, No. 10, 07.03.1997, p. 6393-6398.

Research output: Contribution to journalArticle

Hao, Weihua ; Tan, Zheng ; Prasad, Kondury ; Reddy, K. Kishta ; Chen, Jian ; Prestwich, Glenn D. ; Falck, J R ; Shears, Stephen B. ; Lafer, Eileen M. / Regulation of AP-3 function by inositides. Identification of phosphatidylinositol 3,4,5-trisphosphate as a potent ligand. In: Journal of Biological Chemistry. 1997 ; Vol. 272, No. 10. pp. 6393-6398.
@article{28b7c9ea3a8040b5b7acb746ded844bc,
title = "Regulation of AP-3 function by inositides. Identification of phosphatidylinositol 3,4,5-trisphosphate as a potent ligand",
abstract = "As part of the growing effort to understand the role inositol phosphates and inositol lipids play in the regulation of vesicle traffic within nerve terminals, we determined whether or not the synapse-specific clathrin assembly protein AP-3 can interact with inositol lipids. We found that soluble dioctanoyl-phosphatidylinositol 3,4,5-trisphosphate (DiC8PtdIns(3,4,5)P3) was only 7.5-fold weaker a ligand than D-myo-inositol hexakisphosphate in assays that measured the displacement of D-myo- [3H]inositol hexakisphosphate. In functional assays we found that both of these ligands inhibited clathrin assembly, but DiC8-PtdIns(3,4,5)P3 was more potent and exhibited a larger maximal effect. We also examined the structural features of DiCs-PtdIns(3,4,5)P3 that establish specificity. Dioctanoyl-phosphatidylinositol 3,4-bisphosphate, which does not have a 5- phosphate, and 4,5-O-bisphosphoryl-D-myo-inosityl 1-O-(1,2-O-diundecyl)-sn- 3-glycerylphosphate, which does not have a 3-phosphate, were, respectively, 2-fold and 4-fold less potent than DiC8-PtdIns(3,4,5)P3 as inhibitors of clathrin assembly. Deacylation of DiCs-PtdIns(3,4,5)P3 reduced its affinity for AP-3 almost 20-fold, and also dramatically lowered its ability to inhibit clathrin assembly. The deacylated products of the soluble derivatives of phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 4,5- bisphosphate were both not significant inhibitors of clathrin assembly. It therefore appears that the interactions of inositides with AP-3 should not be considered simply in terms of electrostatic effects of the highly charged phosphate groups. Ligand specificity appears also to be mediated by hydrophobic interactions with the fatty-acyl chains of the inositol lipids.",
author = "Weihua Hao and Zheng Tan and Kondury Prasad and Reddy, {K. Kishta} and Jian Chen and Prestwich, {Glenn D.} and Falck, {J R} and Shears, {Stephen B.} and Lafer, {Eileen M.}",
year = "1997",
month = "3",
day = "7",
doi = "10.1074/jbc.272.10.6393",
language = "English (US)",
volume = "272",
pages = "6393--6398",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "10",

}

TY - JOUR

T1 - Regulation of AP-3 function by inositides. Identification of phosphatidylinositol 3,4,5-trisphosphate as a potent ligand

AU - Hao, Weihua

AU - Tan, Zheng

AU - Prasad, Kondury

AU - Reddy, K. Kishta

AU - Chen, Jian

AU - Prestwich, Glenn D.

AU - Falck, J R

AU - Shears, Stephen B.

AU - Lafer, Eileen M.

PY - 1997/3/7

Y1 - 1997/3/7

N2 - As part of the growing effort to understand the role inositol phosphates and inositol lipids play in the regulation of vesicle traffic within nerve terminals, we determined whether or not the synapse-specific clathrin assembly protein AP-3 can interact with inositol lipids. We found that soluble dioctanoyl-phosphatidylinositol 3,4,5-trisphosphate (DiC8PtdIns(3,4,5)P3) was only 7.5-fold weaker a ligand than D-myo-inositol hexakisphosphate in assays that measured the displacement of D-myo- [3H]inositol hexakisphosphate. In functional assays we found that both of these ligands inhibited clathrin assembly, but DiC8-PtdIns(3,4,5)P3 was more potent and exhibited a larger maximal effect. We also examined the structural features of DiCs-PtdIns(3,4,5)P3 that establish specificity. Dioctanoyl-phosphatidylinositol 3,4-bisphosphate, which does not have a 5- phosphate, and 4,5-O-bisphosphoryl-D-myo-inosityl 1-O-(1,2-O-diundecyl)-sn- 3-glycerylphosphate, which does not have a 3-phosphate, were, respectively, 2-fold and 4-fold less potent than DiC8-PtdIns(3,4,5)P3 as inhibitors of clathrin assembly. Deacylation of DiCs-PtdIns(3,4,5)P3 reduced its affinity for AP-3 almost 20-fold, and also dramatically lowered its ability to inhibit clathrin assembly. The deacylated products of the soluble derivatives of phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 4,5- bisphosphate were both not significant inhibitors of clathrin assembly. It therefore appears that the interactions of inositides with AP-3 should not be considered simply in terms of electrostatic effects of the highly charged phosphate groups. Ligand specificity appears also to be mediated by hydrophobic interactions with the fatty-acyl chains of the inositol lipids.

AB - As part of the growing effort to understand the role inositol phosphates and inositol lipids play in the regulation of vesicle traffic within nerve terminals, we determined whether or not the synapse-specific clathrin assembly protein AP-3 can interact with inositol lipids. We found that soluble dioctanoyl-phosphatidylinositol 3,4,5-trisphosphate (DiC8PtdIns(3,4,5)P3) was only 7.5-fold weaker a ligand than D-myo-inositol hexakisphosphate in assays that measured the displacement of D-myo- [3H]inositol hexakisphosphate. In functional assays we found that both of these ligands inhibited clathrin assembly, but DiC8-PtdIns(3,4,5)P3 was more potent and exhibited a larger maximal effect. We also examined the structural features of DiCs-PtdIns(3,4,5)P3 that establish specificity. Dioctanoyl-phosphatidylinositol 3,4-bisphosphate, which does not have a 5- phosphate, and 4,5-O-bisphosphoryl-D-myo-inosityl 1-O-(1,2-O-diundecyl)-sn- 3-glycerylphosphate, which does not have a 3-phosphate, were, respectively, 2-fold and 4-fold less potent than DiC8-PtdIns(3,4,5)P3 as inhibitors of clathrin assembly. Deacylation of DiCs-PtdIns(3,4,5)P3 reduced its affinity for AP-3 almost 20-fold, and also dramatically lowered its ability to inhibit clathrin assembly. The deacylated products of the soluble derivatives of phosphatidylinositol 3,4-bisphosphate and phosphatidylinositol 4,5- bisphosphate were both not significant inhibitors of clathrin assembly. It therefore appears that the interactions of inositides with AP-3 should not be considered simply in terms of electrostatic effects of the highly charged phosphate groups. Ligand specificity appears also to be mediated by hydrophobic interactions with the fatty-acyl chains of the inositol lipids.

UR - http://www.scopus.com/inward/record.url?scp=0030893931&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030893931&partnerID=8YFLogxK

U2 - 10.1074/jbc.272.10.6393

DO - 10.1074/jbc.272.10.6393

M3 - Article

VL - 272

SP - 6393

EP - 6398

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 10

ER -