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Lima K, Carvalho MFL, Pereira-Martins DA, Nogueira FL, de Miranda LBL, do Nascimento MC, Cavaglieri RDC, Schuringa JJ, Machado-Neto JA, Rego EM. Pharmacological Inhibition of PIP4K2 Potentiates Venetoclax-Induced Apoptosis in Acute Myeloid Leukemia. Int J Mol Sci 2023; 24:16899. [PMID: 38069220 PMCID: PMC10706459 DOI: 10.3390/ijms242316899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/15/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
Phosphatidylinositol-5-phosphate 4-kinase type 2 (PIP4K2) protein family members (PIP4K2A, PIP4K2B, and PIP4K2C) participate in the generation of PIP4,5P2, which acts as a secondary messenger in signal transduction, a substrate for metabolic processes, and has structural functions. In patients with acute myeloid leukemia (AML), high PIP4K2A and PIP4K2C levels are independent markers of a worse prognosis. Recently, our research group reported that THZ-P1-2 (PIP4K2 pan-inhibitor) exhibits anti-leukemic activity by disrupting mitochondrial homeostasis and autophagy in AML models. In the present study, we characterized the expression of PIP4K2 in the myeloid compartment of hematopoietic cells, as well as in AML cell lines and clinical samples with different genetic abnormalities. In ex vivo assays, PIP4K2 expression levels were related to sensitivity and resistance to several antileukemia drugs and highlighted the association between high PIP4K2A levels and resistance to venetoclax. The combination of THZ-P1-2 and venetoclax showed potentiating effects in reducing viability and inducing apoptosis in AML cells. A combined treatment differentially modulated multiple genes, including TAp73, BCL2, MCL1, and BCL2A1. In summary, our study identified the correlation between the expression of PIP4K2 and the response to antineoplastic agents in ex vivo assays in AML and exposed vulnerabilities that may be exploited in combined therapies, which could result in better therapeutic responses.
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Affiliation(s)
- Keli Lima
- Laboratory of Medical Investigation in Pathogenesis and Targeted Therapy in Onco-Immuno-Hematology (LIM-31), Department of Internal Medicine, Hematology Division, Faculdade de Medicina, University of São Paulo, São Paulo CEP 13566-590, Brazil; (K.L.); (D.A.P.-M.); (F.L.N.); (M.C.d.N.)
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo CEP 13566-590, Brazil; (M.F.L.C.); (L.B.L.d.M.); (R.d.C.C.); (J.A.M.-N.)
| | - Maria Fernanda Lopes Carvalho
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo CEP 13566-590, Brazil; (M.F.L.C.); (L.B.L.d.M.); (R.d.C.C.); (J.A.M.-N.)
| | - Diego Antonio Pereira-Martins
- Laboratory of Medical Investigation in Pathogenesis and Targeted Therapy in Onco-Immuno-Hematology (LIM-31), Department of Internal Medicine, Hematology Division, Faculdade de Medicina, University of São Paulo, São Paulo CEP 13566-590, Brazil; (K.L.); (D.A.P.-M.); (F.L.N.); (M.C.d.N.)
- Department of Experimental Hematology, University of Groningen, 9718 BG Groningen, The Netherlands;
| | - Frederico Lisboa Nogueira
- Laboratory of Medical Investigation in Pathogenesis and Targeted Therapy in Onco-Immuno-Hematology (LIM-31), Department of Internal Medicine, Hematology Division, Faculdade de Medicina, University of São Paulo, São Paulo CEP 13566-590, Brazil; (K.L.); (D.A.P.-M.); (F.L.N.); (M.C.d.N.)
| | - Lívia Bassani Lins de Miranda
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo CEP 13566-590, Brazil; (M.F.L.C.); (L.B.L.d.M.); (R.d.C.C.); (J.A.M.-N.)
| | - Mariane Cristina do Nascimento
- Laboratory of Medical Investigation in Pathogenesis and Targeted Therapy in Onco-Immuno-Hematology (LIM-31), Department of Internal Medicine, Hematology Division, Faculdade de Medicina, University of São Paulo, São Paulo CEP 13566-590, Brazil; (K.L.); (D.A.P.-M.); (F.L.N.); (M.C.d.N.)
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo CEP 13566-590, Brazil; (M.F.L.C.); (L.B.L.d.M.); (R.d.C.C.); (J.A.M.-N.)
| | - Rita de Cássia Cavaglieri
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo CEP 13566-590, Brazil; (M.F.L.C.); (L.B.L.d.M.); (R.d.C.C.); (J.A.M.-N.)
| | - Jan Jacob Schuringa
- Department of Experimental Hematology, University of Groningen, 9718 BG Groningen, The Netherlands;
| | - João Agostinho Machado-Neto
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo CEP 13566-590, Brazil; (M.F.L.C.); (L.B.L.d.M.); (R.d.C.C.); (J.A.M.-N.)
| | - Eduardo Magalhães Rego
- Laboratory of Medical Investigation in Pathogenesis and Targeted Therapy in Onco-Immuno-Hematology (LIM-31), Department of Internal Medicine, Hematology Division, Faculdade de Medicina, University of São Paulo, São Paulo CEP 13566-590, Brazil; (K.L.); (D.A.P.-M.); (F.L.N.); (M.C.d.N.)
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Wei L, Xu M, Liu Z, Jiang C, Lin X, Hu Y, Wen X, Zou R, Peng C, Lin H, Wang G, Yang L, Fang L, Yang M, Zhang P. Hit Identification Driven by Combining Artificial Intelligence and Computational Chemistry Methods: A PI5P4K-β Case Study. J Chem Inf Model 2023; 63:5341-5355. [PMID: 37549337 DOI: 10.1021/acs.jcim.3c00543] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2023]
Abstract
Computer-aided drug design (CADD), especially artificial intelligence-driven drug design (AIDD), is increasingly used in drug discovery. In this paper, a novel and efficient workflow for hit identification was developed within the ID4Inno drug discovery platform, featuring innovative artificial intelligence, high-accuracy computational chemistry, and high-performance cloud computing. The workflow was validated by discovering a few potent hit compounds (best IC50 is ∼0.80 μM) against PI5P4K-β, a novel anti-cancer target. Furthermore, by applying the tools implemented in ID4Inno, we managed to optimize these hit compounds and finally obtained five hit series with different scaffolds, all of which showed high activity against PI5P4K-β. These results demonstrate the effectiveness of ID4inno in driving hit identification based on artificial intelligence, computational chemistry, and cloud computing.
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Affiliation(s)
- Lin Wei
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Min Xu
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Zhiqiang Liu
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Chongguo Jiang
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Xiaohua Lin
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Yaogang Hu
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Xiaoming Wen
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Rongfeng Zou
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Chunwang Peng
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Hongrui Lin
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Guo Wang
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Lijun Yang
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Lei Fang
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Mingjun Yang
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
| | - Peiyu Zhang
- Shenzhen Jingtai Technology Co., Ltd. (XtalPi), Shenzhen 518000, China
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Burke JE, Triscott J, Emerling BM, Hammond GRV. Beyond PI3Ks: targeting phosphoinositide kinases in disease. Nat Rev Drug Discov 2022; 22:357-386. [PMID: 36376561 PMCID: PMC9663198 DOI: 10.1038/s41573-022-00582-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2022] [Indexed: 11/16/2022]
Abstract
Lipid phosphoinositides are master regulators of almost all aspects of a cell's life and death and are generated by the tightly regulated activity of phosphoinositide kinases. Although extensive efforts have focused on drugging class I phosphoinositide 3-kinases (PI3Ks), recent years have revealed opportunities for targeting almost all phosphoinositide kinases in human diseases, including cancer, immunodeficiencies, viral infection and neurodegenerative disease. This has led to widespread efforts in the clinical development of potent and selective inhibitors of phosphoinositide kinases. This Review summarizes our current understanding of the molecular basis for the involvement of phosphoinositide kinases in disease and assesses the preclinical and clinical development of phosphoinositide kinase inhibitors.
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Affiliation(s)
- John E. Burke
- grid.143640.40000 0004 1936 9465Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia Canada ,grid.17091.3e0000 0001 2288 9830Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia Canada
| | - Joanna Triscott
- grid.5734.50000 0001 0726 5157Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Brooke M. Emerling
- grid.479509.60000 0001 0163 8573Sanford Burnham Prebys, La Jolla, CA USA
| | - Gerald R. V. Hammond
- grid.21925.3d0000 0004 1936 9000Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA USA
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Ravi A, Palamiuc L, Emerling BM. Crucial Players for Inter-Organelle Communication: PI5P4Ks and Their Lipid Product PI-4,5-P 2 Come to the Surface. Front Cell Dev Biol 2022; 9:791758. [PMID: 35071233 PMCID: PMC8776650 DOI: 10.3389/fcell.2021.791758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 11/24/2021] [Indexed: 11/23/2022] Open
Abstract
While organelles are individual compartments with specialized functions, it is becoming clear that organellar communication is essential for maintaining cellular homeostasis. This cooperation is carried out by various interactions taking place on the membranes of organelles. The membranes themselves contain a multitude of proteins and lipids that mediate these connections and one such class of molecules facilitating these relations are the phospholipids. There are several phospholipids, but the focus of this perspective is on a minor group called the phosphoinositides and specifically, phosphatidylinositol 4,5-bisphosphate (PI-4,5-P2). This phosphoinositide, on intracellular membranes, is largely generated by the non-canonical Type II PIPKs, namely, Phosphotidylinositol-5-phosphate-4-kinases (PI5P4Ks). These evolutionarily conserved enzymes are emerging as key stress response players in cells. Further, PI5P4Ks have been shown to modulate pathways by regulating organelle crosstalk, revealing roles in preserving metabolic homeostasis. Here we will attempt to summarize the functions of the PI5P4Ks and their product PI-4,5-P2 in facilitating inter-organelle communication and how they impact cellular health as well as their relevance to human diseases.
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Affiliation(s)
- Archna Ravi
- Cell and Molecular Biology of Cancer Program, Sanford Burnham Prebys, La Jolla, CA, United States
| | - Lavinia Palamiuc
- Cell and Molecular Biology of Cancer Program, Sanford Burnham Prebys, La Jolla, CA, United States
| | - Brooke M Emerling
- Cell and Molecular Biology of Cancer Program, Sanford Burnham Prebys, La Jolla, CA, United States
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Arora GK, Palamiuc L, Emerling BM. Expanding role of PI5P4Ks in cancer: A promising druggable target. FEBS Lett 2022; 596:3-16. [PMID: 34822164 PMCID: PMC9154051 DOI: 10.1002/1873-3468.14237] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/04/2021] [Accepted: 11/15/2021] [Indexed: 12/14/2022]
Abstract
Cancer cells are challenged by a myriad of microenvironmental stresses, and it is their ability to efficiently adapt to the constantly changing nutrient, energy, oxidative, and/or immune landscape that allows them to survive and proliferate. Such adaptations, however, result in distinct vulnerabilities that are attractive therapeutic targets. Phosphatidylinositol 5-phosphate 4-kinases (PI5P4Ks) are a family of druggable stress-regulated phosphoinositide kinases that become conditionally essential as a metabolic adaptation, paving the way to targeting cancer cell dependencies. Further, PI5P4Ks have a synthetic lethal interaction with the tumor suppressor p53, the loss of which is one of the most prevalent genetic drivers of malignant transformation. PI5P4K's emergence as a crucial axis in the expanding landscape of phosphoinositide signaling in cancer has already stimulated the development of specific inhibitors. Thus, a better understanding of the biology of the PI5P4Ks will allow for targeted and effective therapeutic interventions. Here, we attempt to summarize the mounting roles of the PI5P4Ks in cancer, including evidence that targeting them is a therapeutic vulnerability and promising next-in-line treatment for multiple cancer subtypes.
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Affiliation(s)
- Gurpreet K Arora
- Cell and Molecular Biology of Cancer Program, Sanford Burnham Prebys, La Jolla, CA, USA
| | - Lavinia Palamiuc
- Cell and Molecular Biology of Cancer Program, Sanford Burnham Prebys, La Jolla, CA, USA
| | - Brooke M Emerling
- Cell and Molecular Biology of Cancer Program, Sanford Burnham Prebys, La Jolla, CA, USA
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Pharmacological inhibition of PI5P4Kα/β disrupts cell energy metabolism and selectively kills p53-null tumor cells. Proc Natl Acad Sci U S A 2021; 118:2002486118. [PMID: 34001596 DOI: 10.1073/pnas.2002486118] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Most human cancer cells harbor loss-of-function mutations in the p53 tumor suppressor gene. Genetic experiments have shown that phosphatidylinositol 5-phosphate 4-kinase α and β (PI5P4Kα and PI5P4Kβ) are essential for the development of late-onset tumors in mice with germline p53 deletion, but the mechanism underlying this acquired dependence remains unclear. PI5P4K has been previously implicated in metabolic regulation. Here, we show that inhibition of PI5P4Kα/β kinase activity by a potent and selective small-molecule probe disrupts cell energy homeostasis, causing AMPK activation and mTORC1 inhibition in a variety of cell types. Feedback through the S6K/insulin receptor substrate (IRS) loop contributes to insulin hypersensitivity and enhanced PI3K signaling in terminally differentiated myotubes. Most significantly, the energy stress induced by PI5P4Kαβ inhibition is selectively toxic toward p53-null tumor cells. The chemical probe, and the structural basis for its exquisite specificity, provide a promising platform for further development, which may lead to a novel class of diabetes and cancer drugs.
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Kalli AC, Reithmeier RAF. Interaction of the human erythrocyte Band 3 anion exchanger 1 (AE1, SLC4A1) with lipids and glycophorin A: Molecular organization of the Wright (Wr) blood group antigen. PLoS Comput Biol 2018; 14:e1006284. [PMID: 30011272 PMCID: PMC6080803 DOI: 10.1371/journal.pcbi.1006284] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 08/07/2018] [Accepted: 06/08/2018] [Indexed: 11/29/2022] Open
Abstract
The Band 3 (AE1, SLC4A1) membrane protein is found in red blood cells and in kidney where it functions as an electro-neutral chloride/bicarbonate exchanger. In this study, we have used molecular dynamics simulations to provide the first realistic model of the dimeric membrane domain of human Band 3 in an asymmetric lipid bilayer containing a full complement of phospholipids, including phosphatidylinositol 4,5–bisphosphate (PIP2) and cholesterol, and its partner membrane protein Glycophorin A (GPA). The simulations show that the annular layer in the inner leaflet surrounding Band 3 was enriched in phosphatidylserine and PIP2 molecules. Cholesterol was also enriched around Band 3 but also at the dimer interface. The interaction of these lipids with specific sites on Band 3 may play a role in the folding and function of this anion transport membrane protein. GPA associates with Band 3 to form the Wright (Wr) blood group antigen, an interaction that involves an ionic bond between Glu658 in Band 3 and Arg61 in GPA. We were able to recreate this complex by performing simulations to allow the dimeric transmembrane portion of GPA to interact with Band 3 in a model membrane. Large-scale simulations showed that the GPA dimer can bridge Band 3 dimers resulting in the dynamic formation of long strands of alternating Band 3 and GPA dimers. Human Band 3 (AE1, SLC4A1), an abundant 911 amino acid glycoprotein, catalyzes the exchange of bicarbonate and chloride across the red blood cell membrane, a process necessary for efficient respiration. Malfunction of Band 3 leads to inherited diseases such as Southeast Asian Ovalocytosis, hereditary spherocytosis and distal renal tubular acidosis. Despite much available structural and functional data about Band 3, key questions about the conformational changes associated with transport and the molecular details of its interaction with lipids and other proteins remain unanswered. In this study, we have used computer simulations to investigate the dynamics of Band 3 in lipid bilayers that resemble the red blood cell plasma membrane. Our results suggest that negatively charged phospholipids and cholesterol interact strongly with Band 3 forming an annulus around the protein. Glycophorin A (GPA) interacts with Band 3 to form the Wright (Wr) blood group antigen. We were able to recreate this complex and show that GPA promotes the clustering of Band 3 in red blood cell membranes. Understanding the molecular details of the interaction of Band 3 with GPA has provided new insights into the nature of the Wright blood group antigen.
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Affiliation(s)
- Antreas C. Kalli
- Leeds Institute of Cancer and Pathology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
- * E-mail:
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Bruntz RC, Lindsley CW, Brown HA. Phospholipase D signaling pathways and phosphatidic acid as therapeutic targets in cancer. Pharmacol Rev 2015; 66:1033-79. [PMID: 25244928 DOI: 10.1124/pr.114.009217] [Citation(s) in RCA: 165] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Phospholipase D is a ubiquitous class of enzymes that generates phosphatidic acid as an intracellular signaling species. The phospholipase D superfamily plays a central role in a variety of functions in prokaryotes, viruses, yeast, fungi, plants, and eukaryotic species. In mammalian cells, the pathways modulating catalytic activity involve a variety of cellular signaling components, including G protein-coupled receptors, receptor tyrosine kinases, polyphosphatidylinositol lipids, Ras/Rho/ADP-ribosylation factor GTPases, and conventional isoforms of protein kinase C, among others. Recent findings have shown that phosphatidic acid generated by phospholipase D plays roles in numerous essential cellular functions, such as vesicular trafficking, exocytosis, autophagy, regulation of cellular metabolism, and tumorigenesis. Many of these cellular events are modulated by the actions of phosphatidic acid, and identification of two targets (mammalian target of rapamycin and Akt kinase) has especially highlighted a role for phospholipase D in the regulation of cellular metabolism. Phospholipase D is a regulator of intercellular signaling and metabolic pathways, particularly in cells that are under stress conditions. This review provides a comprehensive overview of the regulation of phospholipase D activity and its modulation of cellular signaling pathways and functions.
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Affiliation(s)
- Ronald C Bruntz
- Department of Pharmacology (R.C.B., C.W.L., H.A.B.) and Vanderbilt Center for Neuroscience Drug Discovery (C.W.L.), Vanderbilt University Medical Center; Department of Chemistry, Vanderbilt Institute of Chemical Biology (C.W.L., H.A.B.); Vanderbilt Specialized Chemistry for Accelerated Probe Development (C.W.L.); and Department of Biochemistry, Vanderbilt-Ingram Cancer Center (H.A.B.), Vanderbilt University, Nashville, Tennessee
| | - Craig W Lindsley
- Department of Pharmacology (R.C.B., C.W.L., H.A.B.) and Vanderbilt Center for Neuroscience Drug Discovery (C.W.L.), Vanderbilt University Medical Center; Department of Chemistry, Vanderbilt Institute of Chemical Biology (C.W.L., H.A.B.); Vanderbilt Specialized Chemistry for Accelerated Probe Development (C.W.L.); and Department of Biochemistry, Vanderbilt-Ingram Cancer Center (H.A.B.), Vanderbilt University, Nashville, Tennessee
| | - H Alex Brown
- Department of Pharmacology (R.C.B., C.W.L., H.A.B.) and Vanderbilt Center for Neuroscience Drug Discovery (C.W.L.), Vanderbilt University Medical Center; Department of Chemistry, Vanderbilt Institute of Chemical Biology (C.W.L., H.A.B.); Vanderbilt Specialized Chemistry for Accelerated Probe Development (C.W.L.); and Department of Biochemistry, Vanderbilt-Ingram Cancer Center (H.A.B.), Vanderbilt University, Nashville, Tennessee
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Lima K, Ribeiro DM, Campos PDM, Costa FF, Traina F, Saad STO, Sonati MDF, Machado-Neto JA. Differential profile of PIP4K2A expression in hematological malignancies. Blood Cells Mol Dis 2015; 55:228-35. [PMID: 26227852 DOI: 10.1016/j.bcmd.2015.06.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 06/21/2015] [Indexed: 10/23/2022]
Abstract
PIP4K2A is a lipid kinase that phosphorylates PtdIns5P, generating PtdIns4,5P2. Recently, PIP4K2A was identified as a potential target in acute myeloid leukemia cells. The objective of the present study was to investigate the PIP4K2A expression in hematological malignancies and verify the effects of PIP4K2A silencing on proliferation and survival of leukemia cell lines. PIP4K2A was found to be a cytoplasmic and nuclear protein with reduced levels in leukemia cell lines compared to normal leukocytes. PIP4K2A mRNA levels were significantly reduced in bone marrow cells from acute lymphoid leukemia (ALL) patients compared with healthy donors and in myelodysplastic syndromes (MDS) with ≥5% compared with <5% bone marrow blasts. Low PIP4K2A expression (lowest tertile versus 2 higher tertiles) negatively impacted overall survival of MDS patients by univariate analysis. PIP4K2A silencing did not modulate cell proliferation, clonogenicity and apoptosis of HEL and Namalwa leukemia cells. In summary, we characterized the expression of PIP4K2A in a cohort of patients with hematological malignancies and we found that PIP4K2A mRNA expression is downregulated in RAEB-1/RAEB-2 MDS and ALL cells, and PIP4K2A silencing does not modulate cell survival in HEL and Namalwa leukemia cells.
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Affiliation(s)
- Keli Lima
- Department of Clinical Pathology, School of Medical Sciences, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| | - Daniela Maria Ribeiro
- Department of Clinical Pathology, School of Medical Sciences, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| | - Paula de Melo Campos
- Hematology and Hemotherapy Center, University of Campinas - UNICAMP, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas, São Paulo, Brazil
| | - Fernando Ferreira Costa
- Hematology and Hemotherapy Center, University of Campinas - UNICAMP, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas, São Paulo, Brazil
| | - Fabiola Traina
- Hematology and Hemotherapy Center, University of Campinas - UNICAMP, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas, São Paulo, Brazil
| | - Sara Teresinha Olalla Saad
- Hematology and Hemotherapy Center, University of Campinas - UNICAMP, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas, São Paulo, Brazil
| | - Maria de Fátima Sonati
- Department of Clinical Pathology, School of Medical Sciences, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| | - João Agostinho Machado-Neto
- Hematology and Hemotherapy Center, University of Campinas - UNICAMP, Instituto Nacional de Ciência e Tecnologia do Sangue, Campinas, São Paulo, Brazil.
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Jude JG, Spencer GJ, Huang X, Somerville TDD, Jones DR, Divecha N, Somervaille TCP. A targeted knockdown screen of genes coding for phosphoinositide modulators identifies PIP4K2A as required for acute myeloid leukemia cell proliferation and survival. Oncogene 2015; 34:1253-1262. [PMID: 24681948 PMCID: PMC4130659 DOI: 10.1038/onc.2014.77] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 01/28/2014] [Accepted: 02/20/2014] [Indexed: 02/06/2023]
Abstract
Given the importance of deregulated phosphoinositide (PI) signaling in leukemic hematopoiesis, genes coding for proteins that regulate PI metabolism may have significant and as yet unappreciated roles in leukemia. We performed a targeted knockdown (KD) screen of PI modulator genes in human acute myeloid leukemia (AML) cells and identified candidates required to sustain proliferation or prevent apoptosis. One of these, the lipid kinase phosphatidylinositol-5-phosphate 4-kinase, type II, alpha (PIP4K2A) regulates cellular levels of phosphatidylinositol-5-phosphate (PtsIns5P) and phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P₂). We found PIP4K2A to be essential for the clonogenic and leukemia-initiating potential of human AML cells, and for the clonogenic potential of murine MLL-AF9 AML cells. Importantly, PIP4K2A is also required for the clonogenic potential of primary human AML cells. Its KD results in accumulation of the cyclin-dependent kinase inhibitors CDKN1A and CDKN1B, G₁ cell cycle arrest and apoptosis. Both CDKN1A accumulation and apoptosis were partially dependent on activation of the mTOR pathway. Critically, however, PIP4K2A KD in normal hematopoietic stem and progenitor cells, both murine and human, did not adversely impact either clonogenic or multilineage differentiation potential, indicating a selective dependency that we suggest may be the consequence of the regulation of different transcriptional programs in normal versus malignant cells. Thus, PIP4K2A is a novel candidate therapeutic target in myeloid malignancy.
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Affiliation(s)
- Julian G Jude
- Inositide Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, M20 4BX, United Kingdom
- Leukaemia Biology Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, M20 4BX, United Kingdom
| | - Gary J Spencer
- Leukaemia Biology Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, M20 4BX, United Kingdom
| | - Xu Huang
- Leukaemia Biology Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, M20 4BX, United Kingdom
| | - Tim D D Somerville
- Leukaemia Biology Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, M20 4BX, United Kingdom
| | - David R Jones
- Inositide Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, M20 4BX, United Kingdom
| | - Nullin Divecha
- Inositide Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, M20 4BX, United Kingdom
| | - Tim C P Somervaille
- Leukaemia Biology Laboratory, Cancer Research UK Manchester Institute, The University of Manchester, Manchester, M20 4BX, United Kingdom
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Fiume R, Stijf-Bultsma Y, Shah ZH, Keune WJ, Jones DR, Jude JG, Divecha N. PIP4K and the role of nuclear phosphoinositides in tumour suppression. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:898-910. [PMID: 25728392 DOI: 10.1016/j.bbalip.2015.02.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Revised: 02/03/2015] [Accepted: 02/17/2015] [Indexed: 12/27/2022]
Abstract
Phosphatidylinositol-5-phosphate (PtdIns5P)-4-kinases (PIP4Ks) are stress-regulated lipid kinases that phosphorylate PtdIns5P to generate PtdIns(4,5)P₂. There are three isoforms of PIP4Ks: PIP4K2A, 2B and 2C, which localise to different subcellular compartments with the PIP4K2B isoform being localised predominantly in the nucleus. Suppression of PIP4K expression selectively prevents tumour cell growth in vitro and prevents tumour development in mice that have lost the tumour suppressor p53. p53 is lost or mutated in over 70% of all human tumours. These studies suggest that inhibition of PIP4K signalling constitutes a novel anti-cancer therapeutic target. In this review we will discuss the role of PIP4K in tumour suppression and speculate on how PIP4K modulates nuclear phosphoinositides (PPIns) and how this might impact on nuclear functions to regulate cell growth. This article is part of a Special Issue entitled Phosphoinositides.
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Affiliation(s)
- Roberta Fiume
- Cellular Signalling Laboratory, DIBINEM, University of Bologna, Bologna, Italy.
| | - Yvette Stijf-Bultsma
- Inositide Laboratory, Centre for Biological Sciences, Faculty of Natural & Environmental Sciences, Life Sciences Building 85, University of Southampton, Highfield Campus, Southampton SO17 1BJ, UK
| | - Zahid H Shah
- Inositide Laboratory, Centre for Biological Sciences, Faculty of Natural & Environmental Sciences, Life Sciences Building 85, University of Southampton, Highfield Campus, Southampton SO17 1BJ, UK
| | - Willem Jan Keune
- The Netherlands Cancer Institute, Amsterdam 1066CX, The Netherlands
| | - David R Jones
- Oncology iMED, AstraZeneca, Alderley Park, Macclesfield SK10 4TF, UK
| | - Julian Georg Jude
- IMP - Institute of Molecular Pathology, Vienna Biocenter, Dr. Bohr-Gasse 7, 1030 Vienna, Austria
| | - Nullin Divecha
- Inositide Laboratory, Centre for Biological Sciences, Faculty of Natural & Environmental Sciences, Life Sciences Building 85, University of Southampton, Highfield Campus, Southampton SO17 1BJ, UK.
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12
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PIPKIIα is widely expressed in hematopoietic-derived cells and may play a role in the expression of alpha- and gamma-globins in K562 cells. Mol Cell Biochem 2014; 393:145-53. [DOI: 10.1007/s11010-014-2054-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 04/03/2014] [Indexed: 10/25/2022]
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13
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Keune WJ, Jones DR, Divecha N. PtdIns5P and Pin1 in oxidative stress signaling. Adv Biol Regul 2013; 53:179-189. [PMID: 23602596 DOI: 10.1016/j.jbior.2013.02.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Accepted: 02/21/2013] [Indexed: 06/02/2023]
Abstract
Oxidative signaling is important in cellular health, involved in aging and contributes to the development of several diseases such as cancer, neurodegeneration and diabetes. Correct management of reactive oxygen species (ROS) prevents oxidative stress within cells and is imperative for cellular wellbeing. A key pathway that is regulated by oxidative stress is the activation of proline-directed stress kinases (p38, JNK). Phosphorylation induced by these kinases is often translated into cellular outcome through the recruitment of the prolyl-isomerase Pin1. Pin1 binds to phosphorylated substrates using its WW-domain and can induce conformational changes in the target protein through its prolyl-isomerase activity. We show that exposure of cells to UV irradiation or hydrogen peroxide (H₂O₂), induces the synthesis of the phosphoinositide second messenger PtdIns5P in part by inducing the interaction between phosphatidylinositol-5-phosphate 4-kinase (PIP4K) enzymes that remove PtdIns5P, with Pin1. In response to H₂O₂ exposure, Murine Embryonic Fibroblasts (MEFs) derived from Pin1⁻/⁻ mice showed increased cell viability and an increased abundance of PtdIns5P compared to wild-type MEFs. Decreasing the levels of PtdIns5P in Pin1⁻/⁻ MEFs decreased both their viability in response to H₂O₂ exposure and the expression of genes required for cellular ROS management. The decrease in the expression of these genes manifested itself in the increased accumulation of cellular ROS. These data strongly argue that PtdIns5P acts as a stress-induced second messenger that can calibrate how cells manage ROS.
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Affiliation(s)
- Willem-Jan Keune
- Inositide Laboratory CRUK, The Paterson Institute for Cancer Research, University of Manchester, Manchester M20 4BX, United Kingdom.
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Davis MI, Sasaki AT, Shen M, Emerling BM, Thorne N, Michael S, Pragani R, Boxer M, Sumita K, Takeuchi K, Auld DS, Li Z, Cantley LC, Simeonov A. A homogeneous, high-throughput assay for phosphatidylinositol 5-phosphate 4-kinase with a novel, rapid substrate preparation. PLoS One 2013; 8:e54127. [PMID: 23326584 PMCID: PMC3542272 DOI: 10.1371/journal.pone.0054127] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 12/05/2012] [Indexed: 12/20/2022] Open
Abstract
Phosphoinositide kinases regulate diverse cellular functions and are important targets for therapeutic development for diseases, such as diabetes and cancer. Preparation of the lipid substrate is crucial for the development of a robust and miniaturizable lipid kinase assay. Enzymatic assays for phosphoinositide kinases often use lipid substrates prepared from lyophilized lipid preparations by sonication, which result in variability in the liposome size from preparation to preparation. Herein, we report a homogeneous 1536-well luciferase-coupled bioluminescence assay for PI5P4Kα. The substrate preparation is novel and allows the rapid production of a DMSO-containing substrate solution without the need for lengthy liposome preparation protocols, thus enabling the scale-up of this traditionally difficult type of assay. The Z’-factor value was greater than 0.7 for the PI5P4Kα assay, indicating its suitability for high-throughput screening applications. Tyrphostin AG-82 had been identified as an inhibitor of PI5P4Kα by assessing the degree of phospho transfer of γ-32P-ATP to PI5P; its inhibitory activity against PI5P4Kα was confirmed in the present miniaturized assay. From a pilot screen of a library of bioactive compounds, another tyrphostin, I-OMe tyrphostin AG-538 (I-OMe-AG-538), was identified as an ATP-competitive inhibitor of PI5P4Kα with an IC50 of 1 µM, affirming the suitability of the assay for inhibitor discovery campaigns. This homogeneous assay may apply to other lipid kinases and should help in the identification of leads for this class of enzymes by enabling high-throughput screening efforts.
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Affiliation(s)
- Mindy I. Davis
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Atsuo T. Sasaki
- Beth Israel Deaconess Medical Center, Department of Medicine, Division of Signal Transduction; Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
- Division of Hematology and Oncology, Department of Internal Medicine, Neuroscience Institute: Brain Tumor Center, University of Cincinnati, College of Medicine, Cincinnati, Ohio, United States of America
| | - Min Shen
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Brooke M. Emerling
- Beth Israel Deaconess Medical Center, Department of Medicine, Division of Signal Transduction; Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Natasha Thorne
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Sam Michael
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Rajan Pragani
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Matthew Boxer
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Kazutaka Sumita
- Division of Hematology and Oncology, Department of Internal Medicine, Neuroscience Institute: Brain Tumor Center, University of Cincinnati, College of Medicine, Cincinnati, Ohio, United States of America
| | - Koh Takeuchi
- Biomedicinal Information Research Center, National Institute of Advanced Industrial Science and Technology, Koto, Tokyo, Japan
| | - Douglas S. Auld
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
- Center for Proteomic Chemistry, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Zhuyin Li
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Lewis C. Cantley
- Beth Israel Deaconess Medical Center, Department of Medicine, Division of Signal Transduction; Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Anton Simeonov
- National Institutes of Health Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
- * E-mail:
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15
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Zaccariotto T, Lanaro C, Albuquerque D, Santos M, Bezerra M, Cunha F, Lorand-Metze I, Araujo A, Costa F, Sonati M. Expression profiles of phosphatidylinositol phosphate kinase genes during normal human in vitro erythropoiesis. GENETICS AND MOLECULAR RESEARCH 2012; 11:3861-8. [DOI: 10.4238/2012.november.12.3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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PIP4Kβ interacts with and modulates nuclear localization of the high-activity PtdIns5P-4-kinase isoform PIP4Kα. Biochem J 2010; 430:223-35. [DOI: 10.1042/bj20100341] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The β-isoform of PIP4K (PtdIns5P-4-kinase) regulates the levels of nuclear PtdIns5P, which in turn modulates the acetylation of the tumour suppressor p53. The crystal structure of PIP4Kβ demonstrated that it can form a homodimer with the two subunits arranged in opposite orientations. Using MS, isoform-specific antibodies against PIP4Ks, RNAi (RNA interference) suppression and overexpression studies, we show that PIP4Kβ interacts in vitro and in vivo with the PIP4Kα isoform. As the two isoforms phosphorylate the same substrate to generate the same product, the interaction could be considered to be functionally redundant. However, contrary to expectation, we find that PIP4Kβ has 2000-fold less activity towards PtdIns5P compared with PIP4Kα, and that the majority of PIP4K activity associated with PIP4Kβ comes from its interaction with PIP4Kα. Furthermore, PIP4Kβ can modulate the nuclear localization of PIP4Kα, and PIP4Kα has a role in regulating PIP4Kβ functions. The results of the present study suggest a rationale for the functional interaction between PIP4Kα and PIP4Kβ and provide insight into how the relative levels of the two enzymes may be important in their physiological and pathological roles.
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17
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Barlow CA, Laishram RS, Anderson RA. Nuclear phosphoinositides: a signaling enigma wrapped in a compartmental conundrum. Trends Cell Biol 2009; 20:25-35. [PMID: 19846310 DOI: 10.1016/j.tcb.2009.09.009] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 09/27/2009] [Accepted: 09/28/2009] [Indexed: 01/09/2023]
Abstract
While the presence of phosphoinositides in the nuclei of eukaryotes and the identity of the enzymes responsible for their metabolism have been known for some time, their functions in the nucleus are only now emerging. This is illustrated by the recent identification of effectors for nuclear phosphoinositides. Like the cytosolic phosphoinositide signaling pathway, nuclear phosphatidylinositol 4,5-bisphosphate (PI4,5P(2)) is at the center of the pathway and acts both as a messenger and as a precursor for many additional messengers. Here, recent advances in the understanding of nuclear phosphoinositide signaling and its functions are reviewed with an emphasis on PI4,5P(2) and its role in gene expression. The compartmentalization of nuclear phosphoinositide phosphates (PIP(n)) remains a mystery, but emerging evidence suggests that phosphoinositides occupy several functionally distinct compartments.
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Affiliation(s)
- Christy A Barlow
- University of Wisconsin-Madison, Department of Pharmacology, 1300 University Ave. University of Wisconsin Medical School, Madison, WI 53706, USA
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18
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Stace C, Manifava M, Delon C, Coadwell J, Cockcroft S, Ktistakis NT. PA binding of phosphatidylinositol 4-phosphate 5-kinase. ACTA ACUST UNITED AC 2007; 48:55-72. [PMID: 18167315 DOI: 10.1016/j.advenzreg.2007.11.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Catherine Stace
- Signalling Programme, Babraham Institute, Babraham, Cambridge CB2 4AT, UK
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19
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Heck JN, Mellman DL, Ling K, Sun Y, Wagoner MP, Schill NJ, Anderson RA. A conspicuous connection: structure defines function for the phosphatidylinositol-phosphate kinase family. Crit Rev Biochem Mol Biol 2007; 42:15-39. [PMID: 17364683 DOI: 10.1080/10409230601162752] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The phosphatidylinositol phosphate (PIP) kinases are a unique family of enzymes that generate an assortment of lipid messengers, including the pivotal second messenger phosphatidylinositol 4,5-bisphosphate (PI4,5P2). While members of the PIP kinase family function by catalyzing a similar phosphorylation reaction, the specificity loop of each PIP kinase subfamily determines substrate preference and partially influences distinct subcellular targeting. Specific protein-protein interactions that are unique to particular isoforms or splice variants play a key role in targeting PIP kinases to appropriate subcellular compartments to facilitate the localized generation of PI4,5P2 proximal to effectors, a mechanism key for the function of PI4,5P2 as a second messenger. This review documents the discovery of the PIP kinases and their signaling products, and summarizes our current understanding of the mechanisms underlying the localized generation of PI4,5P2 by PIP kinases for the regulation of cellular events including actin cytoskeleton dynamics, vesicular trafficking, cell migration, and an assortment of nuclear events.
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Affiliation(s)
- Jessica N Heck
- Program in Molecular and Cellular Pharmacology, Department of Pharmacology, University of Wisconsin-Madison, University of Wisconsin Medical School, Madison, WI 53706, USA
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20
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Im YJ, Davis AJ, Perera IY, Johannes E, Allen NS, Boss WF. The N-terminal membrane occupation and recognition nexus domain of Arabidopsis phosphatidylinositol phosphate kinase 1 regulates enzyme activity. J Biol Chem 2007; 282:5443-52. [PMID: 17197438 DOI: 10.1074/jbc.m611342200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The type I B family of phosphatidylinositol phosphate kinases (PIPKs) contain a characteristic region of Membrane Occupation and Recognition Nexus (MORN) motifs at the N terminus. These MORN motifs are not found in PIPKs from other eukaryotes. To understand the impact of the additional N-terminal domain on protein function and subcellular distribution, we expressed truncated and full-length versions of AtPIPK1, one member of this family of PIPKs, in Escherichia coli and in tobacco cells grown in suspension culture. Deletion of the N-terminal MORN domain (amino acids 1-251) of AtPIPK1 increased the specific activity of the remaining C-terminal peptide (DeltaMORN) >4-fold and eliminated activation by phosphatidic acid (PtdOH). PtdOH activation could also be eliminated by mutating Pro(396) to Ala (P396A) in the predicted linker region between the MORN and the kinase homology domains. AtPIPK1 is product-activated and the MORN domain binds PtdIns(4,5)P(2). Adding back the MORN peptide to DeltaMORN or to the PtdOH-activated full-length protein increased activity approximately 2-fold. Furthermore, expressing the MORN domain in vivo increased the plasma membrane PtdInsP kinase activity. When cells were exposed to hyperosmotic stress, the MORN peptide redistributed from the plasma membrane to a lower phase or endomembrane fraction. In addition, endogenous PtdInsP kinase activity increased in the endomembrane fraction of hyperosmotically stressed cells. We conclude that the MORN peptide can regulate both the function and distribution of the enzyme in a manner that is sensitive to the lipid environment.
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Affiliation(s)
- Yang Ju Im
- Plant Biology, North Carolina State University, Raleigh, North Carolina 27695-7649, USA
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21
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Schulze H, Korpal M, Hurov J, Kim SW, Zhang J, Cantley LC, Graf T, Shivdasani RA. Characterization of the megakaryocyte demarcation membrane system and its role in thrombopoiesis. Blood 2006; 107:3868-75. [PMID: 16434494 PMCID: PMC1895279 DOI: 10.1182/blood-2005-07-2755] [Citation(s) in RCA: 149] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
To produce blood platelets, megakaryocytes elaborate proplatelets, accompanied by expansion of membrane surface area and dramatic cytoskeletal rearrangements. The invaginated demarcation membrane system (DMS), a hallmark of mature cells, has been proposed as the source of proplatelet membranes. By direct visualization of labeled DMS, we demonstrate that this is indeed the case. Late in megakaryocyte ontogeny, the DMS gets loaded with PI-4,5-P(2), a phospholipid that is confined to plasma membranes in other cells. Appearance of PI-4,5-P(2) in the DMS occurs in proximity to PI-5-P-4-kinase alpha (PIP4Kalpha), and short hairpin (sh) RNA-mediated loss of PIP4Kalpha impairs both DMS development and expansion of megakaryocyte size. Thus, PI-4,5-P(2) is a marker and possibly essential component of internal membranes. PI-4,5-P(2) is known to promote actin polymerization by activating Rho-like GTPases and Wiskott-Aldrich syndrome (WASp) family proteins. Indeed, PI-4,5-P(2) in the megakaryocyte DMS associates with filamentous actin. Expression of a dominant-negative N-WASp fragment or pharmacologic inhibition of actin polymerization causes similar arrests in proplatelet formation, acting at a step beyond expansion of the DMS and cell mass. These observations collectively suggest a signaling pathway wherein PI-4,5-P(2) might facilitate DMS development and local assembly of actin fibers in preparation for platelet biogenesis.
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Affiliation(s)
- Harald Schulze
- Dana-Farber Cancer Institute, One Jimmy Fund Way, Boston, MA 02115, USA
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22
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Abstract
Proteins that make, consume, and bind to phosphoinositides are important for constitutive membrane traffic. Different phosphoinositides are concentrated in different parts of the central vacuolar pathway, with phosphatidylinositol 4-phosphate predominate on Golgi, phosphatidylinositol 4,5-bisphosphate predominate at the plasma membrane, phosphatidylinositol 3-phosphate the major phosphoinositide on early endosomes, and phosphatidylinositol 3,5-bisphosphate found on late endocytic organelles. This spatial segregation may be the mechanism by which the direction of membrane traffic is controlled. Phosphoinositides increase the affinity of membranes for peripheral membrane proteins that function for sorting protein cargo or for the docking and fusion of transport vesicles. This implies that constitutive membrane traffic may be regulated by the mechanisms that control the activity of the enzymes that produce and consume phosphoinositides. Although the lipid kinases and phosphatases that function in constitutive membrane traffic are beginning to be identified, their regulation is poorly understood.
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Affiliation(s)
- Michael G Roth
- Dept. of Biochemistry, Univ. of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd., Dallas, TX 75390-9038, USA.
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23
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Tolias K, Carpenter CL. In vitro interaction of phosphoinositide-4-phosphate 5-kinases with Rac. Methods Enzymol 2001; 325:190-200. [PMID: 11036604 DOI: 10.1016/s0076-6879(00)25443-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Affiliation(s)
- K Tolias
- Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
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24
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Shyng SL, Barbieri A, Gumusboga A, Cukras C, Pike L, Davis JN, Stahl PD, Nichols CG. Modulation of nucleotide sensitivity of ATP-sensitive potassium channels by phosphatidylinositol-4-phosphate 5-kinase. Proc Natl Acad Sci U S A 2000; 97:937-41. [PMID: 10639183 PMCID: PMC15434 DOI: 10.1073/pnas.97.2.937] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
ATP-sensitive potassium channels (K(ATP) channels) regulate cell excitability in response to metabolic changes. K(ATP) channels are formed as a complex of a sulfonylurea receptor (SURx), a member of the ATP-binding cassette protein family, and an inward rectifier K(+) channel subunit (Kir6.x). Membrane phospholipids, in particular phosphatidylinositol (PI) 4,5-bisphosphate (PIP(2)), activate K(ATP) channels and antagonize ATP inhibition of K(ATP) channels when applied to inside-out membrane patches. To examine the physiological relevance of this regulatory mechanism, we manipulated membrane PIP(2) levels by expressing either the wild-type or an inactive form of PI-4-phosphate 5-kinase (PIP5K) in COSm6 cells and examined the ATP sensitivity of coexpressed K(ATP) channels. Channels from cells expressing the wild-type PIP5K have a 6-fold lower ATP sensitivity (K(1/2), the half maximal inhibitory concentration, approximately 60 microM) than the sensitivities from control cells (K(1/2) approximately 10 microM). An inactive form of the PIP5K had little effect on the K(1/2) of wild-type channels but increased the ATP-sensitivity of a mutant K(ATP) channel that has an intrinsically lower ATP sensitivity (from K(1/2) approximately 450 microM to K(1/2) approximately 100 microM), suggesting a decrease in membrane PIP(2) levels as a consequence of a dominant-negative effect of the inactive PIP5K. These results show that PIP5K activity, which regulates PIP(2) and PI-3,4,5-P(3) levels, is a significant determinant of the physiological nucleotide sensitivity of K(ATP) channels.
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Affiliation(s)
- S L Shyng
- Department of Cell Biology and Physiology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
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25
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Anderson RA, Boronenkov IV, Doughman SD, Kunz J, Loijens JC. Phosphatidylinositol phosphate kinases, a multifaceted family of signaling enzymes. J Biol Chem 1999; 274:9907-10. [PMID: 10187762 DOI: 10.1074/jbc.274.15.9907] [Citation(s) in RCA: 229] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- R A Anderson
- Department of Pharmacology, University of Wisconsin Medical School, Madison, Wisconsin 53706, USA.
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26
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Vancurova I, Choi JH, Lin H, Kuret J, Vancura A. Regulation of phosphatidylinositol 4-phosphate 5-kinase from Schizosaccharomyces pombe by casein kinase I. J Biol Chem 1999; 274:1147-55. [PMID: 9873063 DOI: 10.1074/jbc.274.2.1147] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phosphatidylinositol ()P 5-kinase (PtdIns(4)P 5-kinase) catalyzes the last step in the synthesis of phosphatidylinositol 4, 5-bisphosphate (PtdIns(4,5)P2). PtdIns(4,5)P2 is a precursor of diacylglycerol and inositol 1,4,5-trisphosphate and is also involved in regulation of actin cytoskeleton remodeling and membrane traffic. To satisfy such varied demands in several aspects of cell physiology, synthesis of PtdIns(4,5)P2 must be stringently regulated. In this paper we describe extraction, purification, and characterization of PtdIns(4)P 5-kinase from the plasma membranes of Schizosaccharomyces pombe. We also provide evidence that PtdIns(4)P 5-kinase is phosphorylated and inactivated by Cki1, the S. pombe homolog of casein kinase I. Phosphorylation by Cki1 in vitro decreases the activity of PtdIns(4)P 5-kinase. In addition, and most importantly, overexpression of Cki1 in S. pombe results in a reduced synthesis of PtdIns(4,5)P2 and in a lower activity of PtdIns(4)P 5-kinase associated with the plasma membrane. These results suggest that PtdIns(4)P 5-kinase is a target of Cki1 in S. pombe and that Cki1 is involved in regulation of PtdIns(4, 5)P2 synthesis by phosphorylating and inactivating PtdIns(4)P 5-kinase.
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Affiliation(s)
- I Vancurova
- Department of Biological Sciences, St. John's University, Jamaica, New York 11439, USA.
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27
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Hinchliffe KA, Ciruela A, Irvine RF. PIPkins1, their substrates and their products: new functions for old enzymes. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1436:87-104. [PMID: 9838059 DOI: 10.1016/s0005-2760(98)00140-4] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The phosphatidylinositolphosphate kinases (PIPkins) are a unique family of enzymes that catalyse the production of phosphorylated inositol lipids. Recent advances have revealed that, due to their ability to utilise a number of different lipid substrates (at least in vitro), this family is potentially able to generate several distinct, physiologically important inositol lipids. Despite their importance, however, our understanding of the regulation of the PIPkins and of their physiological role in cellular signalling and regulation is still poor. Here we describe in turn the diverse physiological functions of the known substrates and major products of the PIPkins. We then examine what is known about the members of the PIPkin family themselves, and their characteristics and regulation.
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Affiliation(s)
- K A Hinchliffe
- University of Cambridge, Department of Pharmacology, Tennis Court Road, Cambridge CB2 1QJ, UK.
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28
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Abstract
Phosphatidylinositol, a component of eukaryotic cell membranes, is unique among phospholipids in that its head group can be phosphorylated at multiple free hydroxyls. Several phosphorylated derivatives of phosphatidylinositol, collectively termed phosphoinositides, have been identified in eukaryotic cells from yeast to mammals. Phosphoinositides are involved in the regulation of diverse cellular processes, including proliferation, survival, cytoskeletal organization, vesicle trafficking, glucose transport, and platelet function. The enzymes that phosphorylate phosphatidylinositol and its derivatives are termed phosphoinositide kinases. Recent advances have challenged previous hypotheses about the substrate selectivity of different phosphoinositide kinase families. Here we re-examine the pathways of phosphoinositide synthesis and the enzymes involved.
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Affiliation(s)
- D A Fruman
- Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA.
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Rameh LE, Tolias KF, Duckworth BC, Cantley LC. A new pathway for synthesis of phosphatidylinositol-4,5-bisphosphate. Nature 1997; 390:192-6. [PMID: 9367159 DOI: 10.1038/36621] [Citation(s) in RCA: 352] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Phosphatidylinositol-4,5-bisphosphate (PtdIns-4,5-P2), a key molecule in the phosphoinositide signalling pathway, was thought to be synthesized exclusively by phosphorylation of PtdIns-4-P at the D-5 position of the inositol ring. The enzymes that produce PtdIns-4,5-P2 in vitro fall into two related subfamilies (type I and type II PtdInsP-5-OH kinases, or PIP(5)Ks) based on their enzymatic properties and sequence similarities'. Here we have reinvestigated the substrate specificities of these enzymes. As expected, the type I enzyme phosphorylates PtdIns-4-P at the D-5 position of the inositol ring. Surprisingly, the type II enzyme, which is abundant in some tissues, phosphorylates PtdIns-5-P at the D-4 position, and thus should be considered as a 4-OH kinase, or PIP(4)K. The earlier error in characterizing the activity of the type II enzyme is due to the presence of contaminating PtdIns-5-P in commercial preparations of PtdIns-4-P. Although PtdIns-5-P was previously thought not to exist in vivo, we find evidence for the presence of this lipid in mammalian fibroblasts, establishing a new pathway for PtdIns-4,5-P2 synthesis.
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Affiliation(s)
- L E Rameh
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA.
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30
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Zhang X, Loijens JC, Boronenkov IV, Parker GJ, Norris FA, Chen J, Thum O, Prestwich GD, Majerus PW, Anderson RA. Phosphatidylinositol-4-phosphate 5-kinase isozymes catalyze the synthesis of 3-phosphate-containing phosphatidylinositol signaling molecules. J Biol Chem 1997; 272:17756-61. [PMID: 9211928 DOI: 10.1074/jbc.272.28.17756] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Phosphatidylinositol-4-phosphate 5-kinases (PIP5Ks) utilize phosphatidylinositols containing D-3-position phosphates as substrates to form phosphatidylinositol 3,4-bisphosphate. In addition, type I PIP5Ks phosphorylate phosphatidylinositol 3, 4-bisphosphate to phosphatidylinositol 3,4,5-trisphosphate, while type II kinases have less activity toward this substrate. Remarkably, these kinases can convert phosphatidylinositol 3-phosphate to phosphatidylinositol 3,4,5-trisphosphate in a concerted reaction. Kinase activities toward the 3-position phosphoinositides are comparable with those seen with phosphatidylinositol 4-phosphate as the substrate. Therefore, the PIP5Ks can synthesize phosphatidylinositol 4,5-bisphosphate and two 3-phosphate-containing polyphosphoinositides. These unexpected activities position the PIP5Ks as potential participants in the generation of all polyphosphoinositide signaling molecules.
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Affiliation(s)
- X Zhang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63100, USA
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31
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Canales J, Buitrago F, Faraldo A, Avalos M, Cameselle JC. Identification of rat liver glucose-3-phosphatase as an inositol monophosphatase inhibited by lithium. Arch Biochem Biophys 1997; 343:27-34. [PMID: 9210643 DOI: 10.1006/abbi.1997.0130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Glucose-3-phosphatase (Glc3Pase) from rat liver has been purified 780-fold with a 4% recovery. The substrate specificity of the purified enzyme agreed with that of inositol monophosphatase (EC 3.1.3.25). D-Glucose 3-phosphate (D-Glc(3)P; K(m) = 200 microM) was hydrolyzed with an efficiency similar to DL-myo-inositol 1-monophosphate (DL-Ins(1)P; K(m) = 80 microM), since the ratio V(max)/K(m) was similar for both substrates. Purification data, coelution of activities, thermal inactivation curves, optimal pH, bivalent cation requirements, inhibition by Li+, molecular weight, and isoelectric pH comparisons supported that the hydrolysis of D-Glc(3)P and DL-Ins(1)P was catalyzed by a unique phosphohydrolase identified as a hepatic form of the lithium-sensitive inositol monophosphatase. That the hydrolysis of D-Glc(3)P is a genuine feature of inositol monophosphatases was confirmed because the enzyme purified from bovine brain showed also Glc3Pase activity, and inspection of published 3D models of inositol monophosphatase complexes with D(L)-Ins(1)P or D(L)-Ins(4)P indicated that beta(alpha)-D-Glc(3)P in a pyranose conformation with all (but one) the hydroxy groups in equatorial orientation would fit in the active site as other good substrates do. The results of this work are suggestive of possible relationships between inositol and sugar 3-phosphate metabolism.
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Affiliation(s)
- J Canales
- Unidad de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain
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32
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Saito S, Goto K, Tonosaki A, Kondo H. Gene cloning and characterization of CDP-diacylglycerol synthase from rat brain. J Biol Chem 1997; 272:9503-9. [PMID: 9083091 DOI: 10.1074/jbc.272.14.9503] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A cDNA encoded a 462-amino acid protein, which showed CDP-diacylglycerol synthase (CDS) activity was cloned for the first time as the vertebrate enzyme molecule from rat brain cDNA library. The deduced molecular mass of this rat CDS was 53 kDa, and putative primary structure included several possible membrane- spanning regions. At the amino acid sequence level, rat CDS shared 55.5%, 31. 7%, and 20.9% identity with already known Drosophila, Saccharomyces cerevisiae, and Escherichia coli CDS, respectively. This rat CDS preferred 1-stearoyl-2-arachidonoyl phosphatidic acid as a substrate, and its activity was strongly inhibited by phosphatidylglycerol 4, 5-bisphosphate. By immunoblotting analysis of COS cells overexpressed with the epitope-tagged for rat CDS, a 60-kDa band was detected. By epitope-tag immunocytochemistry, the CDS protein was mainly localized in close association with the membrane of the endoplasmic reticulum of the transfected cells. The intense mRNA expression of CDS was localized in the cerebellar Purkinje cells, the pineal body, and the inner segment of photoreceptor cells. Additionally, very intense expression was detected in postmitotic spermatocytes and spermatids.
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Affiliation(s)
- S Saito
- Department of Anatomy, Tohoku University School of Medicine, Sendai 980-77, Japan
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33
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Castellino AM, Parker GJ, Boronenkov IV, Anderson RA, Chao MV. A novel interaction between the juxtamembrane region of the p55 tumor necrosis factor receptor and phosphatidylinositol-4-phosphate 5-kinase. J Biol Chem 1997; 272:5861-70. [PMID: 9038203 DOI: 10.1074/jbc.272.9.5861] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Tumor necrosis factor-alpha (TNF-alpha) binding to its receptors leads to a diversity of biological responses. The actions of TNF are the result of the interaction of cytoplasmic proteins that bind directly to the intracellular domains of the two TNF receptors, p55 and p75. Here we report a novel interaction between the juxtamembrane region of the p55 TNF receptor and a newly discovered 47-kDa isoform of phosphatidylinositol-4-phosphate 5-kinase (PIP5K), a member of the enzyme family that generates the key signaling messenger, phosphatidylinositol 4,5-bisphosphate. The interaction was found to be specific for the p55 TNF receptor and was not observed with the p75 TNF receptor, the Fas antigen, or the p75 neurotrophin receptor, which are other members of the TNF receptor superfamily. In vitro experiments using recombinant fusion proteins verify the authenticity of the interaction between the p55 receptor and PIP5KIIbeta, a new isoform of PIP5K, but not the previously identified 53-kDa PIP5KIIalpha. Treatment of HeLa cells with TNF-alpha resulted in an increased PIP5K activity. These results indicate that phosphatidylinositol turnover may be linked to stimulation of the p55 TNF receptor and suggest that a subset of TNF responses may result from the direct association of PIP5KIIbeta with the p55 TNF receptor.
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Affiliation(s)
- A M Castellino
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York, New York 10021, USA
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34
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Loijens JC, Anderson RA. Type I phosphatidylinositol-4-phosphate 5-kinases are distinct members of this novel lipid kinase family. J Biol Chem 1996; 271:32937-43. [PMID: 8955136 DOI: 10.1074/jbc.271.51.32937] [Citation(s) in RCA: 173] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Phosphatidylinositol-4-phosphate 5-kinases (PIP5K) synthesize phosphatidylinositol-4,5-bisphosphate, a key precursor in phosphoinositide signaling that also regulates some proteins and cellular processes directly. Two distinct PIP5Ks have been characterized in erythrocytes, the 68-kDa type I (PIP5KI) and 53-kDa type II (PIP5KII) isoforms. Using peptide sequences from the erythroid 68-kDa PIP5KI, we have isolated cDNAs encoding PIP5KIalpha from human brain. Partial cDNAs obtained for a second isoform, PIP5KIbeta, established that the human STM7 gene encoded a previously unrecognized PIP5KI. However, the peptide sequences demonstrated that erythroid PIP5KI corresponded to PIP5KIalpha. Recombinant, bacterially expressed PIP5KIalpha possessed PIP5K activity and was immunoreactive with erythroid PIP5KI antibodies. By Northern analysis, PIP5KIalpha and PIP5KIbeta had wide tissue distributions, but their expression levels differed greatly. PIP5KIs had homology to the kinase domains of PIP5KIIalpha, yeast Mss4p and Fab1p, and a new Caenorhabditis elegans Fab1-like protein identified in the data base. These new isoforms have refined the sequence requirements for PIP5K activity and, potentially, regulation of these enzymes. Furthermore, the limited homology between PIP5KIs and PIP5KIIalpha, which was almost exclusively within the kinase domain core, provided a molecular basis for distinction between type I and II PIP5Ks.
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Affiliation(s)
- J C Loijens
- Program in Cellular and Molecular Biology and Department of Pharmacology, University of Wisconsin Medical School, Madison, Wisconsin 53706, USA.
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35
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Kwok F, Humpage A, Cheng CH. Phosphatidylinositol phosphate 5-kinase: purification and inhibition studies. Prep Biochem Biotechnol 1996; 26:1-19. [PMID: 8744418 DOI: 10.1080/10826069608000046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A membrane-associated phosphatidylinositol phosphate 5-kinase has been purified approximately 110,000-fold from sheep brains. The purification procedure involves: sodium chloride (1M) extraction of the membrane, 20-40% ammonium sulfate fractionation, phosphocellulose (P-11) chromatography, a second phosphocellulose chromatography, hydroxyapatite chromatography, heparin Sepharose chromatography, HPLC SP(SO3- polymer)-cation exchange chromatography, and HPLC gel filtration. The purified enzyme exhibited a final specific activity of 1750 nmole/min/mg of protein. The molecular mass of the enzyme was estimated to be approximately 60 kDa by SDS-PAGE and 130 kDa by HPLC gel filtration. Kinetic measurements showed that the apparent Km value of phosphatidylinositol phosphate 5-kinase for the utilization of ATP is 43 microM. The 2'(3')-0-(2,4,6-trinitrophenyl) derivative of ATP was found to be an inhibitor of the enzyme. The mode of inhibition is competitive, with a Ki value of 55 microM.
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Affiliation(s)
- F Kwok
- Department of Applied Biology & Chemical Technology, Hong Kong Polytechnic University, Hung Hom, Hong Kong
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36
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Loijens JC, Boronenkov IV, Parker GJ, Anderson RA. The phosphatidylinositol 4-phosphate 5-kinase family. ADVANCES IN ENZYME REGULATION 1996; 36:115-40. [PMID: 8869744 DOI: 10.1016/0065-2571(95)00005-4] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The existence of a PIP5K family of enzymes has been suggested by Western blotting and purification of numerous PIP5Ks from various tissues and cell types. The erythrocyte has at least two PIP5Ks, named PIP5KI and PIP5KII, while the brain appears to have even more isoforms. The cloning of the first PIP5K, the PIP5KII alpha, is just the beginning of the molecular classification of this protein family. The PIP5KII alpha sequence has shown that these enzymes lack obvious homology to protein, sugar and other lipid kinases. The identification of two S. cerevisiae homologues, Mss4p and Fab1p, confirms that this family of kinases is widely distributed in eukaryotes. Not surprisingly, cloning experiments have identified additional isoforms. By cloning additional isoforms, insights into the structure and functions of this family of enzymes will be gained. One reason for a large family of PIP5Ks is that many forms of regulation and cellular functions have been ascribed to PIP5Ks, as summarized in Figure 10. Some of these functional links result from PtdIns[4,5]P2 being required for a given process, but the direct involvement of specific PIP5Ks is not well defined. Which PIP5K isoforms are regulated by a specific mechanism or are involved in a cellular process often is not clear. For example, which PIP5Ks produce PtdIns[4,5]P2 that is hydrolyzed by PLC or phosphorylated by the PI 3-kinase is not known. A few exceptions are PIP5KII not being able to phosphorylate PtdIns[4,5]P2 in native membranes, and PIP5KIs being stimulated by PtdA, required for secretion, and possibly regulated by G proteins of the Rho subfamily. The multiplicity of regulation and functions of each PIP5K isoform remains to be elucidated. Another factor governing the number of isoforms may be presence of multiple pools of polyphosphoinositides and the localizing of PIP5K function within cells. The polyphosphoinositides appear to be compartmentalized within cells and each pool appears to be sensitive to specific signals. These polyphosphoinositide pools may include those in the plasma membrane that are used by PLC, nuclear pools that appear to turn over separately from cytoplasmic pools and a small pool at sites of vesicle fusion with the plasma membrane. Each pool may be controlled by a specific PIP5K isoform. This would explain the diversity of PIP5K cellular roles. Another possibility is that the PIP5Ks are localized to certain areas of the cell by being part of a protein or proteolipid complex. Furthermore, the presence of PITP or PLC in the complex would potentially impart specificity and speed on the use of PtdIns[4]P and PtdIns[4,5]P2 because these lipids could be channeled quickly from one enzyme to the next. The concept of localized complexes containing particular PIP5K isoforms that control the composition of different polyphosphoinositide pools will likely be important as the family of PIP5K isoforms grows.
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Affiliation(s)
- J C Loijens
- Department of Pharmacology, University of Wisconsin Medical School, Madison 53706, USA
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37
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Abstract
Rho family GTPases appear to play an important role in the regulation of the actin cytoskeleton, but the mechanism of regulation is unknown. Since phosphoinositide 3-kinase and phosphatidylinositol 4,5-bisphosphate have also been implicated in actin reorganization, we investigated the possibility that Rho family members interact with phosphoinositide kinases. We found that both GTP- and GDP-bound Rac1 associate with phosphatidylinositol-4-phosphate 5-kinase in vitro and in vivo. Phosphoinositide 3-kinase also bound to Rac1 and Cdc42Hs, and these interactions were GTP-dependent. Stimulation of Swiss 3T3 cells with platelet-derived growth factor induced the association of PI 3-kinase with Rac in immunoprecipitates. PI 3-kinase activity was also detected in Cdc42 immunoprecipitates from COS7 cells. These results suggest that phosphoinositide kinases are involved in Rho family signal transduction pathways and raise the possibility that the effects of Rho family members on the actin cytoskeleton are mediated in part by phosphoinositide kinases.
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Affiliation(s)
- K F Tolias
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
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38
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Fisher SK. Homologous and heterologous regulation of receptor-stimulated phosphoinositide hydrolysis. Eur J Pharmacol 1995; 288:231-50. [PMID: 7774668 DOI: 10.1016/0922-4106(95)90035-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Signal transduction at a diverse range of pharmacologically distinct receptors is effected by the enhanced turnover of inositol phospholipids, with the attendant formation of inositol 1,4,5-trisphosphate and diacylglycerol. Although considerable progress has been made in recent years towards the identification and characterization of the individual components of this pathway, much less is known of mechanisms that may underlie its regulation. In this review, evidence is presented for the potential regulation of inositol lipid turnover at the level of receptor, phosphoinositide-specific phospholipase C and substrate availability in response to either homologous or heterologous stimuli. Available data indicate that the extent of receptor-stimulated inositol lipid hydrolysis is regulated by multiple mechanisms that operate at different levels of the signal transduction pathway.
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Affiliation(s)
- S K Fisher
- Neuroscience Laboratory, University of Michigan, Ann Arbor 48104-1687, USA
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39
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Chong LD, Traynor-Kaplan A, Bokoch GM, Schwartz MA. The small GTP-binding protein Rho regulates a phosphatidylinositol 4-phosphate 5-kinase in mammalian cells. Cell 1994; 79:507-13. [PMID: 7954816 DOI: 10.1016/0092-8674(94)90259-3] [Citation(s) in RCA: 550] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Integrin-mediated adhesion is known to stimulate production of phosphatidylinositol 4,5-bisphosphate (4,5-PIP2) and increase 4,5-PIP2 hydrolysis in response to platelet-derived growth factor (PDGF). We now show that treatment of cells with lovastatin, which inhibits modification of small GTP-binding proteins, reduced PIP2 levels and decreased calcium mobilization in response to PDGF and thrombin. In cell lysates, GTP gamma S stimulated PIP 5-kinase activity, and this effect was blocked by botulinum C3 exoenzyme, suggesting that Rho was responsible. GTP-bound recombinant Rho stimulated PIP 5-kinase activity, whereas GDP-Rho was much less potent and GTP-bound Rac was ineffective. Microinjected botulinum C3 exoenzyme caused diminished calcium mobilization in response to PDGF or thrombin. Conversely, microinjection of activated Rho reversed the decrease in calcium mobilization normally seen in nonadherent cells. These data demonstrate that Rho regulates 4,5-PIP2 synthesis and, indirectly, 4,5-PIP2 hydrolysis. They also raise the possibility that PIP2 synthesis could mediate the effects of Rho on the actin cytoskeleton.
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Affiliation(s)
- L D Chong
- Department of Immunology, Scripps Research Institute, La Jolla, California 92037
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40
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Hope H, Pike L. Purification and characterization of a polyphosphoinositide phosphatase from rat brain. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)31564-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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41
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Type I phosphatidylinositol 4-phosphate 5-kinase isoforms are specifically stimulated by phosphatidic acid. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(19)78159-9] [Citation(s) in RCA: 332] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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42
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A specific inhibitor of phosphatidylinositol 3-kinase, 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002). J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)37680-9] [Citation(s) in RCA: 2499] [Impact Index Per Article: 83.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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43
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Stephens LR, Jackson TR, Hawkins PT. Agonist-stimulated synthesis of phosphatidylinositol(3,4,5)-trisphosphate: a new intracellular signalling system? BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1179:27-75. [PMID: 8399352 DOI: 10.1016/0167-4889(93)90072-w] [Citation(s) in RCA: 383] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- L R Stephens
- Department of Development and Signalling, AFRC Babraham Institute, Cambridge, UK
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44
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Tran D, Gascard P, Berthon B, Fukami K, Takenawa T, Giraud F, Claret M. Cellular distribution of polyphosphoinositides in rat hepatocytes. Cell Signal 1993; 5:565-81. [PMID: 8312134 DOI: 10.1016/0898-6568(93)90052-n] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The distribution of total phospholipids, phosphatidylinositol 4-phosphate (PIP) and phosphatidylinositol 4,5-bisphosphate (PIP2) was studied in isolated rat hepatocytes: (i) by mass assay and isotopic labelling in the fractions of plasma membranes, microsomes, mitochondria and nuclei prepared from isolated hepatocytes and (ii) by immunolocalization of PIP2 with a specific antibody (kt3g) in whole hepatocytes and isolated nuclei. Mass measurement and isotopic labelling showed that PIP was distributed in all four fractions. PIP2 was present in the plasma membrane and the nuclei. In whole cells, PIP2 was also detected in the plasma membrane by immunolocalization with the anti-PIP2 antibody kt3g. In unpolarized single hepatocytes, PIP2 distributed evenly throughout the plasma membrane. However, in polarized cell couplets, PIP2 was the most often undetectable in the lateral domain between the cells, and distributed preferentially in the sinusoidal domain of the plasma membrane. These results suggest that hepatocytes segregate PIP2 in particular domains of their plasma membrane. In purified fractions of nuclei, immunolocalization experiments showed that PIP2 was present uniquely in the nuclear envelope.
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Affiliation(s)
- D Tran
- Unité de Recherche INSERM U. 274, Université Paris-Sud, Orsay, France
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45
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Purushotham KR, Nakagawa Y, Kurian P, Patel R, Crews FT, Humphreys-Beher MG. Activation of phosphatidylinositol 3-kinase and phosphatidylinositol 4-kinase during rat parotid acinar cell proliferation. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1178:40-8. [PMID: 8392376 DOI: 10.1016/0167-4889(93)90107-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We have recently shown that beta-adrenergic agonist, isoproterenol-induced parotid acinar cell proliferation is in part mediated by elevated levels of surface galactosyltransferase which undergoes interaction with the EGF-R. The receptor subsequently undergoes autophosphorylation on the tyrosine residues in a manner similar to its 'receptor-ligand' interaction (Purushotham et al. (1992) Biochem. J. 284, 767-776). In this study, we provide evidence for phosphatidylinositol 3-kinase and 4-kinase as cytoplasmic signalling proteins involved in both the isoproterenol and EGF-stimulated signal transduction upon in vitro and in-vivo stimulation of parotid acinar cells. Total cell lysate activity for the PtdIns 4-kinase was 2- and 3-fold higher than unstimulated control cells, while the PtdIns 3-kinase was 1.4- and 2.8-fold higher following stimulation by isoproterenol or EGF, respectively. Increases of 6- and 2-fold in phosphatidylinositol 3-kinase were observed in anti-phosphotyrosine-antibody-immunoprecipitated cell lysates upon in-vitro growth stimulation with isoproterenol or EGF, respectively. There was an increase in tyrosine phosphorylation of the holoenzyme and association of the p85 subunit of phosphatidylinositol 3-kinase with EGF-R in response to both isoproterenol and EGF treatments. This corresponded with the mobilization of p85 from the cytoplasm to the plasma membrane upon growth stimulation. These results further implicate the phosphoinositide metabolites in the second messenger signalling pathways of isoproterenol-induced rat parotid cell proliferation. The parallel utilization of EGF indicate that the post-transductional mechanisms of isoproterenol-induced acinar cell proliferation are similar to the growth-factor-mediated activation of intracellular signalling pathways for cell growth.
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Affiliation(s)
- K R Purushotham
- Department of Oral Biology, University of Florida, Gainesville
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46
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Schmidt M, Varsányi M, Thieleczek R, Heilmeyer LM. Identification of a new 80 k isoform of phosphatidylinositol 4-phosphate 5-kinase from bovine brain. FEBS Lett 1993; 325:201-4. [PMID: 8391476 DOI: 10.1016/0014-5793(93)81073-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Phosphatidylinositol 4-phosphate 5-kinase is associated with bovine brain microsomes to an extent of approximately 65% of the total cellular enzyme activity. This membrane-associated kinase activity can be solubilized with Triton X-114. Following polyacrylamide gel electrophoresis in the presence of SDS the enzyme can be renaturated from gel slices in the presence of desoxycholate and Triton X-100. Catalytic activity appears at an apparent molecular weight of 80 k. Analysis of the reaction product formed by the 80 k protein reveals the existence of a 5-phosphotransferase, identifying the 80 k polypeptide as a new phosphatidylinositol 4-phosphate 5-kinase isoform.
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Affiliation(s)
- M Schmidt
- Abteilung für Biochemie Supramolekularer Systeme, Ruhr-Universität Bochum, Germany
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47
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Tran D, Noel J, Claret M. [Calcium and liver]. ARCHIVES INTERNATIONALES DE PHYSIOLOGIE, DE BIOCHIMIE ET DE BIOPHYSIQUE 1993; 101:A23-40. [PMID: 7691222 DOI: 10.3109/13813459309008890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Cells expand energy to lower the concentration of free calcium in the cytosol ([Ca2+]i) to a very low level. Extracellular Ca2+ entering via channels situated in the plasma membrane is expelled into the extracellular medium by a Ca(2+)-Mg(2+)-ATPase or by Na(+)-Ca2+ exchangers. The Ca2+ that enters the cell is sequestered, once inside the cytosol, by a Ca(2+)-Mg(2+)-ATPase, which concentrates Ca2+ in specialized domains of the endoplasmic reticulum. The nucleus and the mitochondria also concentrate Ca2+, but less efficiently. The stimulation of numerous receptors by hormones, growth factors and neurotransmitters coupled to GTP-binding proteins provokes a rapid increase in [Ca2+]i by mobilizing Ca2+ from intra- and extracellular compartments. Membrane coupling is ensured by the activation of a phospholipase C-beta, which hydrolyses a doubly phosphorylated phosphoinositide, phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2). The inositol (1,4,5)-trisphosphate (InsP3) consequently formed binds to a receptor consisting in 4 homologous of 250 kDa each. The InsP3 receptor has been localized to a specialized region, rich in Ca2+, of the endoplasmic reticulum. The receptor has been purified and its sequence obtained. Reincorporated into planar bilayers, it displays the properties of a channel. In the cell, opening of the InsP3 receptor-channel provokes the release of the Ca2+ accumulated within the endoplasmic reticulum. Analyzing the kinetics of channel opening by the methods of rapid mixing, rapid filtration or flash photolysis of caged InsP3 has revealed that InsP3 opens the channel within a very short time, probably less than 30 msec. The InsP3 receptor-channel is autoregenerative. With the sustained stimulation of a Ca2+ influx the release of Ca2+ leads to an augmentation of [Ca2+]i, which is responsible for triggering cellular responses. The complexity of Ca2+ signals produced by stimulated cells has been revealed by studies in which highly effective techniques have been used to detect Ca2+ ions in the cytosol, such as bioluminescent proteins, fluorescent indicators or ionic currents sensitive to Ca2+. It appears that variations in [Ca2+]i induced by stimulation consist of oscillations of which the frequency, but not the amplitude, depends on the concentration of the hormone. Moreover, by summing the images picked up with a video recorder, it has been possible to demonstrate the changes in [Ca2+]i at the subcellular level and the waves of Ca2+ in stimulated cells.
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Affiliation(s)
- D Tran
- Unité de Recherche INSERM U.274, Université Paris-Sud, Orsay, France
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48
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Moritz A, Westerman J, De Graan PN, Payrastre B, Gispen WH, Wirtz KW. Characterization of phosphatidylinositol-4-phosphate 5-kinase activities from bovine brain membranes. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1168:79-86. [PMID: 8389203 DOI: 10.1016/0005-2760(93)90269-f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Phosphatidylinositol-4-phosphate (PtdIns(4)P) kinase activity associated with bovine brain membranes, was released by NaCl treatment and partially purified by chromatography on phosphocellulose, phenylsepharose, Ultrogel AcA44, DEAE-cellulose and ATP-agarose. The final preparation contained a 6333-fold purified protein fraction with a specific activity of 171 nmol.min-1 x mg-1. Under conditions where this PtdIns(4)P kinase activity (PtdIns(4)P kinase activity b) did not bind to DEAE-cellulose, a PtdIns(4)P kinase activity purified earlier (Moritz, A., De Graan, P.N.E., Ekhart, P.F., Gispen, W.H. and Wirtz, K.W.A. (1990) J. Neurochem. 54, 351-354) does bind (PtdIns(4)P kinase activity a). Both enzyme activities specifically used PtdIns(4)P as substrate and phosphorylated the inositol moiety at the 5'-position. PtdIns(4) kinase activity a has an apparent Km of 18 microM for PtdIns(4)P whereas PtdIns(4)P kinase activity b has a Km of 4 microM. All other measured kinetic parameters (i.e., Km for ATP, Mg(2+)-dependence, pH optimum, activation by phosphatidylserine and inhibition by phosphatidylinositol 4,5-bisphosphate) were similar for both enzyme activities.
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Affiliation(s)
- A Moritz
- Center for Biomembranes and Lipid Enzymology, Rudolf Magnus Institute, University of Utrecht, The Netherlands
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Rhoda-Hardy-Dessources MD, de Neef RS, Mérault G, Giraud F. Characterization of phosphoinositide kinases in normal and sickle anaemia red cells. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1181:90-6. [PMID: 8384492 DOI: 10.1016/0925-4439(93)90095-i] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
PtdIns and PtdInsP kinases from normal erythrocyte (AA) membranes and sickle cell anaemia erythrocyte (SS) membranes have been characterized. PtdIns kinase was studied in native membranes under conditions in which PtdInsP kinase and PtdInsP phosphatase do not express any activity. Kinetic analysis of the AA and SS PtdIns kinases indicate similar Km values for PtdIns and ATP but higher Vmax values for SS PtdIns kinase. PtdInsP kinase was partially purified from erythrocyte ghosts by NaCl extraction. The kinetic parameters of PtdInsP kinase determined under these conditions were similar in AA and SS NaCl extracts. These data suggest the presence of some effector of PtdIns kinase in SS cell membranes, resulting in a greater activity of the enzyme. This leads consequently, to increase the PtdIns4P pool and to activate PtdInsP kinase, in agreement with our previous observations of a greater [32P]Pi incorporation in both polyphosphoinositides in SS cells relatively to AA cells.
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50
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Bengis-Garber C, Gruener N. Cross-talk between cAMP and formylmet-leu-phe in human neutrophils: phosphorylation of a 52,000 molecular weight protein. Cell Signal 1992; 4:247-60. [PMID: 1324701 DOI: 10.1016/0898-6568(92)90064-f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The mechanism of inhibition of neutrophil phagocytic functions by cAMP-elevating agents has not yet been clarified. In the present work, the effects of adenylate cyclase agonists on protein phosphorylation in the formylmethionyl-leucyl-phenylalanine (fMLP)-stimulated human neutrophils were studied. Before stimulation, 32Pi-labelled cells were incubated with adenosine deaminase to remove the endogenously produced adenosine, an adenylate cyclase agonist itself. A protein of about 52,000 molecular weight was rapidly and transiently phosphorylated when neutrophils were stimulated with fMLP in the presence of isoproterenol, prostaglandin E1, histamine or 2-chloroadenosine. This phosphorylation was blocked by the antagonists of the receptors for the above-listed agents. No phosphorylation of the 52,000 molecular weight protein could be observed if either fMLP or the cAMP-elevating agent were applied alone. A calcium ionophore A23187 and dibutyryl-cAMP could replace fMLP and a cAMP-elevating agent, respectively. Phosphorylation of the 52,000 molecular weight protein was also demonstrated in cell lysates in the presence of cAMP, and in membrane preparations in the presence of the catalytic subunit of cAMP-dependent protein kinase. These data suggest that phosphorylation of the 52,000 molecular weight protein in intact cells is dependent on the cross-talk between the fMLP- and the cAMP-signalling pathways, and may thus be involved in the cAMP-regulatory mechanism.
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Affiliation(s)
- C Bengis-Garber
- Department of Biochemistry, Lady Davis Carmel Hospital, Haifa, Israel
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