Phosphatidylinositol 4-kinase type II  is responsible for the phosphatidylinositol 4-kinase activity associated with synaptic vesicles

The adaptor complex 3 (AP-3) targets membrane proteins from endosomes to lysosomes, lysosome-related organelles and synaptic vesicles. Phosphatidylinositol-4-kinase type II α (PI4KIIα) is one of several proteins possessing catalytic domains that regulate AP-3–dependent sorting. Here we present evidence that PI4KIIα uniquely behaves both as a membrane protein cargo as well as an enzymatic regulator of adaptor function. In fact, AP-3 and PI4KIIα form a complex that requires a dileucine-sorting motif present in PI4KIIα. Mutagenesis of either the PI4KIIα-sorting motif or its kinase-active site indicates that both are necessary to interact with AP-3 and properly localize PI4KIIα to LAMP-1–positive endosomes. Similarly, both the kinase activity and the sorting signal present in PI4KIIα are necessary to rescue endosomal PI4KIIα siRNA-induced mutant phenotypes. We propose a mechanism whereby adaptors use canonical sorting motifs to selectively recruit a regulatory enzymatic activity to restricted membrane domains.

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Nuclear localization of phosphatidylinositol 4-kinase β

Journal of Cell Science ◽

10.1242/jcs.115.8.1769 ◽

2002 ◽

Vol 115 (8) ◽

pp. 1769-1775 ◽

Cited By ~ 2

Author(s):

Petra de Graaf ◽

Elsa E. Klapisz ◽

Thomas K. F. Schulz ◽

Alfons F. M. Cremers ◽

Arie J. Verkleij ◽

...

Keyword(s):

Nuclear Export ◽

Kinase Activity ◽

Insoluble Fraction ◽

Type Ii ◽

3T3 Cells ◽

Type Iii ◽

Pore Complexes ◽

Phosphatidylinositol 4 ◽

Nih 3T3 ◽

Nih 3T3 Cells

Whereas most phosphatidylinositol 4-kinase (PtdIns 4-kinase) activity is localized in the cytoplasm, PtdIns 4-kinase activity has also been detected in membranedepleted nuclei of rat liver and mouse NIH 3T3 cells. Here we have characterized the PtdIns 4-kinase that is present in nuclei from NIH 3T3 cells. Both type II and type III PtdIns 4-kinase activity were observed in the detergent-insoluble fraction of NIH 3T3 cells. Dissection of this fraction into cytoplasmic actin filaments and nuclear lamina-pore complexes revealed that the actin filament fraction contains solely type II PtdIns 4-kinase,whereas lamina-pore complexes contain type III PtdIns 4-kinase activity. Using specific antibodies, the nuclear PtdIns 4-kinase was identified as PtdIns 4-kinase β. Inhibition of nuclear export by leptomycin B resulted in an accumulation of PtdIns 4-kinase β in the nucleus. These data demonstrate that PtdIns 4-kinase β is present in the nuclei of NIH 3T3 fibroblasts,suggesting a specific function for this kinase in nuclear processes.

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Regulation and recruitment of phosphatidylinositol 4-kinase on immature secretory granules is independent of ADP-ribosylation factor 1

Biochemical Journal ◽

10.1042/bj3630289 ◽

2002 ◽

Vol 363 (2) ◽

pp. 289-295 ◽

Cited By ~ 6

Author(s):

Christina PANARETOU ◽

Sharon A. TOOZE

Keyword(s):

Kinase Activity ◽

Secretory Granules ◽

Specific Inhibitor ◽

Small Gtpases ◽

Type Ii ◽

Adp Ribosylation ◽

Lipid Kinases ◽

Phosphatidylinositol 4 ◽

Golgi Network ◽

Adp Ribosylation Factor

Heterotrimeric G-proteins, as well as small GTPases of the Rho and ADP-ribosylation factor (ARF) family, are implicated in the regulation of lipid kinases, including PtdIns 4-kinases and PtdIns(4)P 5-kinases. Here, we describe a PtdIns 4-kinase activity on immature secretory granules (ISGs), regulated secretory organelles formed from the trans-Golgi network (TGN), and investigate the regulation of PtdIns4P levels on these membranes. Over 50% of the PtdIns 4-kinase activity on ISGs is inhibited by both a low concentration of adenosine and the monoclonal antibody 4C5G, a specific inhibitor of the type II PtdIns 4-kinase. Treatment of ISGs with mastoparan 7 (M7) stimulates the type II PtdIns 4-kinase via pertussis-toxin-sensitive Gi/G0 proteins, which, in contrast with previous results obtained with chromaffin granules [Gasman, Chasserot-Golaz, Hubert, Aunis and Bader (1998) J. Biol. Chem. 273, 16913–16920], does not require Rho A, B or C. M7 treatment also leads to an inhibition in the recruitment of ARF to ISG membranes: this inhibition is not dependent on Gi/G0 activation, and is not linked to the stimulation of PtdIns 4-kinase observed with M7. PtdIns 4-kinase activity on ISGs is not regulated by myristoylated ARF1—GTP, in contrast with results obtained with Golgi membranes [Godi, Pertile, Meyers, Marra, Di Tullio, Iurisci, Luini, Corda and De Matteis (1999) Nat. Cell Biol. 1, 280–287; Jones, Morris, Morgan, Kondo, Irvine and Cockcroft (2000) J. Biol. Chem. 275, 13962–13170], whereas ARF1—GTP does regulate the production of PtdIns(4,5)P2. Our results suggest that the regulation of PtdIns 4-kinase on the ISGs differs in comparison with that on the TGN, and might be related to a specific requirement of ISG maturation.

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Purification and characterization of human erythrocyte phosphatidylinositol 4-kinase. Phosphatidylinositol 4-kinase and phosphatidylinositol 3-monophosphate 4-kinase are distinct enzymes

Biochemical Journal ◽

10.1042/bj2840039 ◽

1992 ◽

Vol 284 (1) ◽

pp. 39-45 ◽

Cited By ~ 34

Author(s):

A Graziani ◽

L E Ling ◽

G Endemann ◽

C L Carpenter ◽

L C Cantley

Keyword(s):

Monoclonal Antibody ◽

Human Erythrocyte ◽

Membrane Fraction ◽

Kinase Activity ◽

Bovine Brain ◽

Erythrocyte Membranes ◽

Major Protein ◽

Type Ii ◽

Effective Inhibitor ◽

Phosphatidylinositol 4

PtdIns 4-kinase has been purified 83,000-fold from human erythrocyte membranes. The major protein detected by SDS/PAGE is of molecular mass 56 kDa, and enzymic activity can be renatured from this band of the gel. The characteristics of this enzyme are similar to other type II PtdIns kinases previously described: PtdIns presented in Triton X-100 micelles is preferred as a substrate over PtdIns vesicles, the enzyme possesses a relatively low Km for ATP (20 microM), and adenosine is an effective inhibitor. A monoclonal antibody raised against bovine brain type II PtdIns 4-kinase is an effective inhibitor of the purified enzyme. PtdIns(4,5)P2 inhibits by approx. 50% when added in equimolar amounts with PtdIns; PtdIns4P has little effect on activity. A PtdIns3P 4-kinase activity has also been detected in erythrocyte lysates. Approximately two-thirds of this activity is in the cytosolic fraction and one-third in the membrane fraction. No PtdIns3P 4-kinase activity could be detected in the purified type II PtdIns 4-kinase preparation, nor could this activity be detected in a bovine brain type III PtdIns 4-kinase preparation. The monoclonal antibody that inhibits the type II PtdIns 4-kinase does not affect the PtdIns3P 4-kinase activity in the membrane fraction. The cytosolic PtdIns3P 4-kinase can be efficiently recovered from a 60%-satd.-(NH4)2SO4 precipitate that is virtually free of PtdIns 4-kinase activity. We conclude that PtdIns3P 4-kinase is a new enzyme distinct from previously characterized PtdIns 4-kinases, and that this enzyme prefers PtdIns3P over PtdIns as a substrate.

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Pathophysiological concentrations of amyloid β proteins directly inhibit rat brain and recombinant human type II phosphatidylinositol 4-kinase activity

Journal of Neurochemistry ◽

10.1111/j.1471-4159.2004.02805.x ◽

2004 ◽

Vol 91 (5) ◽

pp. 1164-1170 ◽

Cited By ~ 16

Author(s):

Bo Wu ◽

Kaori Kitagawa ◽

Nan-Yan Zhang ◽

Bing Liu ◽

Chiyoko Inagaki

Keyword(s):

Rat Brain ◽

Kinase Activity ◽

Amyloid Β ◽

Type Ii ◽

Human Type ◽

Phosphatidylinositol 4

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Relationship between Type II Phosphatidylinositol 4-kinase Activity and Protein Tyrosine Phosphorylation in Membranes from Normal and Sickle Red Cells

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1996.00549.x ◽

1996 ◽

Vol 235 (3) ◽

pp. 549-556 ◽

Cited By ~ 10

Author(s):

Rene-Serge Neef ◽

Marie-Dominique Hardy-Dessources ◽

Francoise Giraud

Keyword(s):

Tyrosine Phosphorylation ◽

Kinase Activity ◽

Red Cells ◽

Type Ii ◽

Protein Tyrosine Phosphorylation ◽

Protein Tyrosine ◽

Phosphatidylinositol 4

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Identification of Key Phospholipids That Bind and Activate Atypical PKCs

Biomedicines ◽

10.3390/biomedicines9010045 ◽

2021 ◽

Vol 9 (1) ◽

pp. 45

Author(s):

Suresh Velnati ◽

Sara Centonze ◽

Federico Girivetto ◽

Daniela Capello ◽

Ricardo M. Biondi ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Phosphatidic Acid ◽

Kinase Activity ◽

Membrane Lipids ◽

Atypical Protein Kinase C ◽

Atypical Protein Kinase ◽

Kinase C ◽

Specific Regulation ◽

Phosphatidylinositol 4

PKCζ and PKCι/λ form the atypical protein kinase C subgroup, characterised by a lack of regulation by calcium and the neutral lipid diacylglycerol. To better understand the regulation of these kinases, we systematically explored their interactions with various purified phospholipids using the lipid overlay assays, followed by kinase activity assays to evaluate the lipid effects on their enzymatic activity. We observed that both PKCζ and PKCι interact with phosphatidic acid and phosphatidylserine. Conversely, PKCι is unique in binding also to phosphatidylinositol-monophosphates (e.g., phosphatidylinositol 3-phosphate, 4-phosphate, and 5-phosphate). Moreover, we observed that phosphatidylinositol 4-phosphate specifically activates PKCι, while both isoforms are responsive to phosphatidic acid and phosphatidylserine. Overall, our results suggest that atypical Protein kinase C (PKC) localisation and activity are regulated by membrane lipids distinct from those involved in conventional PKCs and unveil a specific regulation of PKCι by phosphatidylinositol-monophosphates.

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