1
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Chi ES, Stivison EA, Blind RD. SF-1 Induces Nuclear PIP2. Biomolecules 2023; 13:1509. [PMID: 37892191 PMCID: PMC10604688 DOI: 10.3390/biom13101509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/06/2023] [Accepted: 10/07/2023] [Indexed: 10/29/2023] Open
Abstract
Metazoan cell nuclei contain non-membrane pools of the phosphoinositide lipid PI(4,5)P2 (PIP2), but how this hydrophobic lipid exists within the aqueous nucleoplasm remains unclear. Steroidogenic Factor-1 (NR5A1, SF-1) is a nuclear receptor that binds PIP2 in vitro, and a co-crystal structure of the complex suggests the acyl chains of PIP2 are hidden in the hydrophobic core of the SF-1 protein while the PIP2 headgroup is solvent-exposed. This binding mode explains how SF-1 can solubilize nuclear PIP2; however, cellular evidence that SF-1 expression associates with nuclear PIP2 has been lacking. Here, we examined if tetracycline induction of SF-1 expression would associate with nuclear accumulation of PIP2, using antibodies directed against the PIP2 headgroup. Indeed, tetracycline induction of wild-type SF-1 induced a signal in the nucleus of HEK cells that cross-reacts with PIP2 antibodies, but did not cross-react with antibodies against the lower abundance phosphoinositide PI(3,4,5)P3 (PIP3). The nuclear PIP2 signal co-localized with FLAG-tagged SF-1 in the nuclear compartment. To determine if the nuclear PIP2 signal was dependent on the ability of SF-1 to bind PIP2, we examined a "pocket mutant" of SF-1 (A270W, L345F) shown to be deficient in phospholipid binding by mass spectrometry. Tetracycline induction of this pocket mutant SF-1 in HEK cells failed to induce a detectable PIP2 antibody cross-reactive signal, despite similar Tet-induced expression levels of the wild-type and pocket mutant SF-1 proteins in these cells. Together, these data are the first to suggest that expression of SF-1 induces a PIP2 antibody cross-reactive signal in the nucleus, consistent with X-ray crystallographic and biochemical evidence suggesting SF-1 binds PIP2 in human cells.
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Affiliation(s)
| | | | - Raymond D. Blind
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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2
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Beon J, Han S, Yang H, Park SE, Hyun K, Lee SY, Rhee HW, Seo JK, Kim J, Kim S, Lee D. Inositol polyphosphate multikinase physically binds to the SWI/SNF complex and modulates BRG1 occupancy in mouse embryonic stem cells. eLife 2022; 11:73523. [PMID: 35551737 PMCID: PMC9098221 DOI: 10.7554/elife.73523] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 04/26/2022] [Indexed: 11/13/2022] Open
Abstract
Inositol polyphosphate multikinase (IPMK), a key enzyme in inositol polyphosphate (IP) metabolism, is a pleiotropic signaling factor involved in major biological events, including transcriptional control. In the yeast, IPMK and its IP products promote the activity of the chromatin remodeling complex SWI/SNF, which plays a critical role in gene expression by regulating chromatin accessibility. However, the direct link between IPMK and chromatin remodelers remains unclear, raising the question of how IPMK contributes to transcriptional regulation in mammals. By employing unbiased screening approaches and in vivo/in vitro immunoprecipitation, here we demonstrate that mammalian IPMK physically interacts with the SWI/SNF complex by directly binding to SMARCB1, BRG1, and SMARCC1. Furthermore, we identified the specific domains required for IPMK-SMARCB1 binding. Notably, using CUT&RUN and ATAC-seq assays, we discovered that IPMK co-localizes with BRG1 and regulates BRG1 localization as well as BRG1-mediated chromatin accessibility in a genome-wide manner in mouse embryonic stem cells. Together, these findings show that IPMK regulates the promoter targeting of the SWI/SNF complex, thereby contributing to SWI/SNF-meditated chromatin accessibility, transcription, and differentiation in mouse embryonic stem cells.
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Affiliation(s)
- Jiyoon Beon
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Sungwook Han
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Hyeokjun Yang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Seung Eun Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Kwangbeom Hyun
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,Department of Chemistry, Seoul National University, Seoul, Republic of Korea
| | - Song-Yi Lee
- Department of Chemistry, Seoul National University, Seoul, Republic of Korea
| | - Hyun-Woo Rhee
- Department of Chemistry, Seoul National University, Seoul, Republic of Korea
| | - Jeong Kon Seo
- UNIST Central Research Facilities (UCRF), Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Jaehoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Seyun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,KAIST Stem Cell Center, KAIST, Daejeon, Republic of Korea.,KAIST Institute for the BioCentury, KAIST, Daejeon, Republic of Korea
| | - Daeyoup Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
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3
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Ren D, Sun Y, Li D, Wu H, Jin X. USP22-mediated deubiquitination of PTEN inhibits pancreatic cancer progression by inducing p21 expression. Mol Oncol 2022; 16:1200-1217. [PMID: 34743406 PMCID: PMC8895442 DOI: 10.1002/1878-0261.13137] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 09/25/2021] [Accepted: 11/05/2021] [Indexed: 12/14/2022] Open
Abstract
Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is a dual lipid and protein phosphatase. Multiple mechanisms contributing to the regulation of PTEN levels have been identified thus far, including post-translational modifications, epigenetic mechanisms, and transcriptional mechanisms. In the present study, we identified ubiquitin-specific peptidase 22 (USP22) as a novel deubiquitination-modifying enzyme of PTEN. Furthermore, by inducing deubiquitination and inhibiting the degradation of PTEN, USP22 could induce cyclin-dependent kinase inhibitor 1A (CDKN1A, also symboled as p21) expression in pancreatic cancer. Besides, MDM2 proto-oncogene (MDM2) inhibitor enhanced the antipancreatic cancer effects of USP22 overexpression. In addition to its regulation of MDM2-tumor protein p53 (p53) signaling, we found that PTEN could induce p21 expression by interacting with ankyrin repeat and KH domain containing 1 (ANKHD1) and inhibiting ANKHD1 binding to the p21 promoter. Taken together, our results indicate that ANKHD1 and MDM2 might be novel therapeutic targets in pancreatic cancer.
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Affiliation(s)
- Dianyun Ren
- Department of Pancreatic SurgeryUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Sino‐German Laboratory of Personalized Medicine for Pancreatic CancerUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Yan Sun
- Department of Pancreatic SurgeryUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Sino‐German Laboratory of Personalized Medicine for Pancreatic CancerUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Dan Li
- Cardiovascular Medicine DepartmentUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Heshui Wu
- Department of Pancreatic SurgeryUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Sino‐German Laboratory of Personalized Medicine for Pancreatic CancerUnion HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Xin Jin
- Department of UrologyThe Second Xiangya HospitalCentral South UniversityChangshaChina
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4
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Cestari I, Stuart K. The phosphoinositide regulatory network in Trypanosoma brucei: Implications for cell-wide regulation in eukaryotes. PLoS Negl Trop Dis 2020; 14:e0008689. [PMID: 33119588 PMCID: PMC7595295 DOI: 10.1371/journal.pntd.0008689] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The unicellular eukaryote Trypanosoma brucei undergoes extensive cellular and developmental changes during its life cycle. These include regulation of mammalian stage surface antigen variation and surface composition changes between life stages; switching between glycolysis and oxidative phosphorylation; differential mRNA editing; and changes in posttranscriptional gene expression, protein trafficking, organellar function, and cell morphology. These diverse events are coordinated and controlled throughout parasite development, maintained in homeostasis at each life stage, and are essential for parasite survival in both the host and insect vector. Described herein are the enzymes and metabolites of the phosphatidylinositol (PI) cellular regulatory network, its integration with other cellular regulatory systems that collectively control and coordinate these numerous cellular processes, including cell development and differentiation and the many associated complex processes in multiple subcellular compartments. We conclude that this regulation is the product of the organization of these enzymes within the cellular architecture, their activities, metabolite fluxes, and responses to environmental changes via signal transduction and other processes. We describe a paradigm for how these enzymes and metabolites could function to control and coordinate multiple cellular functions. The significance of the PI system's regulatory functions in single-celled eukaryotes to metazoans and their potential as chemotherapeutic targets are indicated.
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Affiliation(s)
- Igor Cestari
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
- Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada
- * E-mail: (IC); (KS)
| | - Kenneth Stuart
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
- * E-mail: (IC); (KS)
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5
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Choi YJ, Saba JD. Sphingosine phosphate lyase insufficiency syndrome (SPLIS): A novel inborn error of sphingolipid metabolism. Adv Biol Regul 2018; 71:128-140. [PMID: 30274713 DOI: 10.1016/j.jbior.2018.09.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 09/12/2018] [Accepted: 09/12/2018] [Indexed: 02/06/2023]
Abstract
Sphingosine-1-phosphate lyase (SPL) is an intracellular enzyme that controls the final step in the sphingolipid degradative pathway, the only biochemical pathway for removal of sphingolipids. Specifically, SPL catalyzes the cleavage of sphingosine 1-phosphate (S1P) at the C2-3 carbon bond, resulting in its irreversible degradation to phosphoethanolamine (PE) and hexadecenal. The substrate of the reaction, S1P, is a bioactive sphingolipid metabolite that signals through a family of five G protein-coupled S1P receptors (S1PRs) to mediate biological activities including cell migration, cell survival/death/proliferation and cell extrusion, thereby contributing to development, physiological functions and - when improperly regulated - the pathophysiology of disease. In 2017, several groups including ours reported a novel childhood syndrome that featured a wide range of presentations including fetal hydrops, steroid-resistant nephrotic syndrome (SRNS), primary adrenal insufficiency (PAI), rapid or insidious neurological deterioration, immunodeficiency, acanthosis and endocrine abnormalities. In all cases, the disease was attributed to recessive mutations in the human SPL gene, SGPL1. We now refer to this condition as SPL Insufficiency Syndrome, or SPLIS. Some features of this new sphingolipidosis were predicted by the reported phenotypes of Sgpl1 homozygous null mice that serve as vertebrate SPLIS disease models. However, other SPLIS features reveal previously unrecognized roles for SPL in human physiology. In this review, we briefly summarize the biochemistry, functions and regulation of SPL, the main clinical and biochemical features of SPLIS and what is known about the pathophysiology of this condition from murine and cell models. Lastly, we consider potential therapeutic strategies for the treatment of SPLIS patients.
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Affiliation(s)
- Youn-Jeong Choi
- UCSF Benioff Children's Hospital Oakland, Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA, 94609, USA
| | - Julie D Saba
- UCSF Benioff Children's Hospital Oakland, Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA, 94609, USA.
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6
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Bryant JM, Blind RD. Signaling through non-membrane nuclear phosphoinositide binding proteins in human health and disease. J Lipid Res 2018; 60:299-311. [PMID: 30201631 DOI: 10.1194/jlr.r088518] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/22/2018] [Indexed: 12/22/2022] Open
Abstract
Phosphoinositide membrane signaling is critical for normal physiology, playing well-known roles in diverse human pathologies. The basic mechanisms governing phosphoinositide signaling within the nucleus, however, have remained deeply enigmatic owing to their presence outside the nuclear membranes. Over 40% of nuclear phosphoinositides can exist in this non-membrane state, held soluble in the nucleoplasm by nuclear proteins that remain largely unidentified. Recently, two nuclear proteins responsible for solubilizing phosphoinositides were identified, steroidogenic factor-1 (SF-1; NR5A1) and liver receptor homolog-1 (LRH-1; NR5A2), along with two enzymes that directly remodel these phosphoinositide/protein complexes, phosphatase and tensin homolog (PTEN; MMAC) and inositol polyphosphate multikinase (IPMK; ipk2). These new footholds now permit the assignment of physiological functions for nuclear phosphoinositides in human diseases, such as endometriosis, nonalcoholic fatty liver disease/steatohepatitis, glioblastoma, and hepatocellular carcinoma. The unique nature of nuclear phosphoinositide signaling affords extraordinary clinical opportunities for new biomarkers, diagnostics, and therapeutics. Thus, phosphoinositide biology within the nucleus may represent the next generation of low-hanging fruit for new drugs, not unlike what has occurred for membrane phosphatidylinositol 3-kinase drug development. This review connects recent basic science discoveries in nuclear phosphoinositide signaling to clinical pathologies, with the hope of inspiring development of new therapies.
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Affiliation(s)
- Jamal M Bryant
- Departments of Pharmacology, Biochemistry, and Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Raymond D Blind
- Departments of Pharmacology, Biochemistry, and Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN 37232
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7
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Kim E, Ahn H, Kim MG, Lee H, Kim S. The Expanding Significance of Inositol Polyphosphate Multikinase as a Signaling Hub. Mol Cells 2017; 40:315-321. [PMID: 28554203 PMCID: PMC5463039 DOI: 10.14348/molcells.2017.0066] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 05/17/2017] [Indexed: 12/20/2022] Open
Abstract
The inositol polyphosphates are a group of multifunctional signaling metabolites whose synthesis is catalyzed by a family of inositol kinases that are evolutionarily conserved from yeast to humans. Inositol polyphosphate multikinase (IPMK) was first identified as a subunit of the arginine-responsive transcription complex in budding yeast. In addition to its role in the production of inositol tetrakis- and pentakisphosphates (IP4 and IP5), IPMK also exhibits phosphatidylinositol 3-kinase (PI3-kinase) activity. Through its PI3-kinase activity, IPMK activates Akt/PKB and its downstream signaling pathways. IPMK also regulates several protein targets non-catalytically via protein-protein interactions. These non-catalytic targets include cytosolic signaling factors and transcription factors in the nucleus. In this review, we highlight the many known functions of mammalian IPMK in controlling cellular signaling networks and discuss future challenges related to clarifying the unknown roles IPMK plays in physiology and disease.
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Affiliation(s)
- Eunha Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| | - Hyoungjoon Ahn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| | - Min Gyu Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| | - Haein Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| | - Seyun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
- KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
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8
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Hamann BL, Blind RD. Nuclear phosphoinositide regulation of chromatin. J Cell Physiol 2017; 233:107-123. [PMID: 28256711 DOI: 10.1002/jcp.25886] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 03/01/2017] [Indexed: 12/26/2022]
Abstract
Phospholipid signaling has clear connections to a wide array of cellular processes, particularly in gene expression and in controlling the chromatin biology of cells. However, most of the work elucidating how phospholipid signaling pathways contribute to cellular physiology have studied cytoplasmic membranes, while relatively little attention has been paid to the role of phospholipid signaling in the nucleus. Recent work from several labs has shown that nuclear phospholipid signaling can have important roles that are specific to this cellular compartment. This review focuses on the nuclear phospholipid functions and the activities of phospholipid signaling enzymes that regulate metazoan chromatin and gene expression. In particular, we highlight the roles that nuclear phosphoinositides play in several nuclear-driven physiological processes, such as differentiation, proliferation, and gene expression. Taken together, the recent discovery of several specifically nuclear phospholipid functions could have dramatic impact on our understanding of the fundamental mechanisms that enable tight control of cellular physiology.
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Affiliation(s)
- Bree L Hamann
- Division of Diabetes Endocrinology and Metabolism, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Raymond D Blind
- Division of Diabetes Endocrinology and Metabolism, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee.,Departments of Medicine, Biochemistry and Pharmacology, Division of Diabetes Endocrinology and Metabolism, The Vanderbilt Diabetes Research and Training Center and the Vanderbilt-Ingram Cancer Center, Nashville, Tennessee
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9
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Poli A, Fiume R, Baldanzi G, Capello D, Ratti S, Gesi M, Manzoli L, Graziani A, Suh PG, Cocco L, Follo MY. Nuclear Localization of Diacylglycerol Kinase Alpha in K562 Cells Is Involved in Cell Cycle Progression. J Cell Physiol 2017; 232:2550-2557. [PMID: 27731506 DOI: 10.1002/jcp.25642] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 10/10/2016] [Indexed: 12/16/2022]
Abstract
Phosphatidylinositol (PI) signaling is an essential regulator of cell motility and proliferation. A portion of PI metabolism and signaling takes place in the nuclear compartment of eukaryotic cells, where an array of kinases and phosphatases localize and modulate PI. Among these, Diacylglycerol Kinases (DGKs) are a class of phosphotransferases that phosphorylate diacylglycerol and induce the synthesis of phosphatidic acid. Nuclear DGKalpha modulates cell cycle progression, and its activity or expression can lead to changes in the phosphorylated status of the Retinoblastoma protein, thus, impairing G1/S transition and, subsequently, inducing cell cycle arrest, which is often uncoupled with apoptosis or autophagy induction. Here we report for the first time not only that the DGKalpha isoform is highly expressed in the nuclei of human erythroleukemia cell line K562, but also that its nuclear activity drives K562 cells through the G1/S transition during cell cycle progression. J. Cell. Physiol. 232: 2550-2557, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Alessandro Poli
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, Institute of Human Anatomy, University of Bologna, Bologna, Italy.,Istituto Nazionale Genetica Molecolare "Romeo e Enrica Invernizzi", Milano, Italy.,Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Roberta Fiume
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, Institute of Human Anatomy, University of Bologna, Bologna, Italy
| | - Gianluca Baldanzi
- Department of Translational Medicine and Institute for Research and Cure of Autoimmune Diseases, University of Piemonte Orientale, Novara, Italy
| | - Daniela Capello
- Department of Translational Medicine and Institute for Research and Cure of Autoimmune Diseases, University of Piemonte Orientale, Novara, Italy
| | - Stefano Ratti
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, Institute of Human Anatomy, University of Bologna, Bologna, Italy
| | - Marco Gesi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Lucia Manzoli
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, Institute of Human Anatomy, University of Bologna, Bologna, Italy
| | - Andrea Graziani
- Department of Translational Medicine and Institute for Research and Cure of Autoimmune Diseases, University of Piemonte Orientale, Novara, Italy.,University Vita e Salute San Raffaele, Milan, Italy
| | - Pann-Ghill Suh
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Lucio Cocco
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, Institute of Human Anatomy, University of Bologna, Bologna, Italy
| | - Matilde Y Follo
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, Institute of Human Anatomy, University of Bologna, Bologna, Italy
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10
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Inositol polyphosphate multikinase (IPMK) in transcriptional regulation and nuclear inositide metabolism. Biochem Soc Trans 2016; 44:279-85. [PMID: 26862216 DOI: 10.1042/bst20150225] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Inositol polyphosphate multikinase (IPMK, ipk2, Arg(82), ArgRIII) is an inositide kinase with unusually flexible substrate specificity and the capacity to partake in many functional protein-protein interactions (PPIs). By merging these two activities, IPMK is able to execute gene regulatory functions that are very unique and only now beginning to be recognized. In this short review, we present a brief history of IPMK, describe the structural biology of the enzyme and highlight a few recent discoveries that have shed more light on the role IPMK plays in inositide metabolism, nuclear signalling and transcriptional regulation.
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11
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Crowder MK, Seacrist CD, Blind RD. Phospholipid regulation of the nuclear receptor superfamily. Adv Biol Regul 2016; 63:6-14. [PMID: 27838257 DOI: 10.1016/j.jbior.2016.10.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 10/24/2016] [Accepted: 10/26/2016] [Indexed: 11/27/2022]
Abstract
Nuclear receptors are ligand-activated transcription factors whose diverse biological functions are classically regulated by cholesterol-based small molecules. Over the past few decades, a growing body of evidence has demonstrated that phospholipids and other similar amphipathic molecules can also specifically bind and functionally regulate the activity of certain nuclear receptors, suggesting a critical role for these non-cholesterol-based molecules in transcriptional regulation. Phosphatidylcholines, phosphoinositides and sphingolipids are a few of the many phospholipid like molecules shown to quite specifically regulate nuclear receptors in mouse models, cell lines and in vitro. More recent evidence has also shown that certain nuclear receptors can "present" a bound phospholipid headgroup to key lipid signaling enzymes, which can then modify the phospholipid headgroup with very unique kinetic properties. Here, we review the broad array of phospholipid/nuclear receptor interactions, from the perspective of the chemical nature of the phospholipid, and the cellular abundance of the phospholipid. We also view the data in the light of well established paradigms for phospholipid mediated transcriptional regulation, as well as newer models of how phospholipids might effect transcription in the acute regulation of complex nuclear signaling pathways. Thus, this review provides novel insight into the new, non-membrane associated roles nuclear phospholipids play in regulating complex nuclear events, centered on the nuclear receptor superfamily of transcription factors.
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Affiliation(s)
- Mark K Crowder
- Department of Pharmacology, Vanderbilt University School of Medicine, USA
| | - Corey D Seacrist
- Department of Pharmacology, Vanderbilt University School of Medicine, USA
| | - Raymond D Blind
- Department of Pharmacology, Vanderbilt University School of Medicine, USA; Department of Biochemistry, Vanderbilt University School of Medicine, USA; Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University School of Medicine, USA.
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12
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Nuclear Lipids in the Nervous System: What they do in Health and Disease. Neurochem Res 2016; 42:321-336. [PMID: 27766461 DOI: 10.1007/s11064-016-2085-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 09/21/2016] [Accepted: 10/11/2016] [Indexed: 12/18/2022]
Abstract
In the last 20 years it has been widely demonstrated that cell nucleus contains neutral and polar lipids localized in nuclear membranes, nucleoli, nuclear matrix and chromatin. Nuclear lipids may show specific organization forming nuclear lipid microdomains and have both structural and functional roles. Depending on their localization, nuclear lipids play different roles such as the regulation of nuclear membrane and nuclear matrix fluidity but they also can act as platforms for vitamin and hormone function, for active chromatin anchoring, and for the regulation of gene expression, DNA duplication and transcription. Crosstalk among different kinds of lipid signalling pathways influence the physiopathology of numerous cell types. In neural cells the nuclear lipids are involved in cell proliferation, differentiation, inflammation, migration and apoptosis. Abnormal metabolism of nuclear lipids might be closely associated with tumorigenesis and neurodegenerative diseases such as Alzheimer disease and Parkinson disease among others.
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13
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Salihovic S, Ganna A, Fall T, Broeckling CD, Prenni JE, van Bavel B, Lind PM, Ingelsson E, Lind L. The metabolic fingerprint of p,p'-DDE and HCB exposure in humans. ENVIRONMENT INTERNATIONAL 2016; 88:60-66. [PMID: 26720637 DOI: 10.1016/j.envint.2015.12.015] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 12/04/2015] [Accepted: 12/14/2015] [Indexed: 06/05/2023]
Abstract
BACKGROUND Dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorobenzene (HCB) are organochlorine pesticides with well-known endocrine disrupting properties. Exposure to p,p'-DDE and HCB concerns human populations worldwide and has been linked to metabolic disorders such as obesity and type 2 diabetes, but details about these associations in humans from the general population are largely unknown. OBJECTIVES We investigated the associations between p,p'-DDE and HCB exposure and global metabolomic profiles in serum samples from 1016 participants from the Swedish population-based Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study. METHODS HCB and p,p'-DDE levels were determined using gas chromatography coupled to high-resolution mass spectrometry (GC-HRMS). Metabolite levels were determined by using a non-targeted metabolomics approach with ultra-performance liquid chromatography coupled to time-of- flight mass spectrometry (UPLC-TOFMS). Association analyses were performed using multivariate linear regression. RESULTS We found circulating levels of p,p-DDE and HCB to be significantly associated with circulating levels of 16 metabolites following adjustment for age, sex, education level, exercise habits, smoking, energy intake, and alcohol intake. The majority of the 16 metabolites belong to lipid metabolism pathways and include fatty acids, glycerophospholipids, sphingolipids, and glycerolipids. Overall, p,p'-DDE and HCB levels were found to be correlated to different metabolites, which suggests that different metabolic fingerprints may be related to circulating levels of these two pesticides. CONCLUSIONS Our findings establish a link between human exposure to organochlorine pesticides and metabolites of key metabolic processes mainly related to human lipid metabolism.
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Affiliation(s)
- Samira Salihovic
- Department of Medical Sciences, Molecular Epidemiology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden; MTM Research Centre, School of Science and Technology, Örebro University, Örebro, Sweden.
| | - Andrea Ganna
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Tove Fall
- Department of Medical Sciences, Molecular Epidemiology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Corey D Broeckling
- Proteomics and Metabolomics Facility, Colorado State University, Fort Collins, CO, USA
| | - Jessica E Prenni
- Proteomics and Metabolomics Facility, Colorado State University, Fort Collins, CO, USA
| | - Bert van Bavel
- MTM Research Centre, School of Science and Technology, Örebro University, Örebro, Sweden
| | - P Monica Lind
- Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University Hospital, Uppsala, Sweden
| | - Erik Ingelsson
- Department of Medical Sciences, Molecular Epidemiology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden; Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Lars Lind
- Department of Medical Sciences, Cardiovascular Epidemiology, Uppsala University, Uppsala, Sweden
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14
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Perdios L, Bunney TD, Warren SC, Dunsby C, French PMW, Tate EW, Katan M. Time-resolved FRET reports FGFR1 dimerization and formation of a complex with its effector PLCγ1. Adv Biol Regul 2016; 60:6-13. [PMID: 26482290 PMCID: PMC4739061 DOI: 10.1016/j.jbior.2015.09.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 09/22/2015] [Indexed: 11/05/2022]
Abstract
In vitro and in vivo imaging of protein tyrosine kinase activity requires minimally invasive, molecularly precise optical probes to provide spatiotemporal mechanistic information of dimerization and complex formation with downstream effectors. We present here a construct with genetically encoded, site-specifically incorporated, bioorthogonal reporter that can be selectively labelled with exogenous fluorogenic probes to monitor the structure and function of fibroblast growth factor receptor (FGFR). GyrB.FGFR1KD.TC contains a coumermycin-induced artificial dimerizer (GyrB), FGFR1 kinase domain (KD) and a tetracysteine (TC) motif that enables fluorescent labelling with biarsenical dyes FlAsH-EDT2 and ReAsH-EDT2. We generated bimolecular system for time-resolved FRET (TR-FRET) studies, which pairs FlAsH-tagged GyrB.FGFR1KD.TC and N-terminal Src homology 2 (nSH2) domain of phospholipase Cγ (PLCγ), a downstream effector of FGFR1, fused to mTurquoise fluorescent protein (mTFP). We demonstrated phosphorylation-dependent TR-FRET readout of complex formation between mTFP.nSH2 and GyrB.FGFR1KD.TC. By further application of TR-FRET, we also demonstrated formation of the GyrB.FGFR1KD.TC homodimer by coumermycin-induced dimerization. Herein, we present a spectroscopic FRET approach to facilitate and propagate studies that would provide structural and functional insights for FGFR and other tyrosine kinases.
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Affiliation(s)
- Louis Perdios
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK; Department of Chemistry, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Tom D Bunney
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Sean C Warren
- Department of Physics, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Christopher Dunsby
- Department of Physics, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Paul M W French
- Department of Physics, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Edward W Tate
- Department of Chemistry, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Matilda Katan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK.
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15
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Yerramilli VS, Scarlata S. The Breast Cancer Susceptibility Gene Product (γ-Synuclein) Alters Cell Behavior through its [corrected] Interaction with Phospholipase Cβ. Cell Signal 2015; 28:91-9. [PMID: 26521046 DOI: 10.1016/j.cellsig.2015.10.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 10/19/2015] [Accepted: 10/27/2015] [Indexed: 12/23/2022]
Abstract
The breast cancer susceptibility gene protein, also known as γ-synuclein, is highly expressed in human breast cancer in a stage-specific manner, with highest expression in late stage cancer. In model systems, γ-synuclein binds phospholipase Cβ2 which is regulated by Gαq to generate intracellular Ca(2+) signals. PLCβ2, which is also absent in normal tissue but highly expressed in breast cancer, is additionally regulated by Rac to promote migration pathways. We have found that γ-synuclein binds to the same region of PLCβ2 as Gαq. Using cells that mimic stage 4 breast cancer (MDA MB 231), we show that down-regulation of γ-synuclein reduces the protein level of PLCβ but increases the transcript level over 40 fold. γ-Synuclein down-regulation also promotes the interaction between Gαq and PLCβ resulting in a stronger Ca(2+) response to Gαq agonists. The ability of γ-synuclein to interfere with Gαq-PLCβ interactions allows more PLCβ to colocalize with Rac impacting Rac-mediated pathways that may give rise to cancerous phenotypes.
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Affiliation(s)
- V Siddartha Yerramilli
- Dept of Physiology & Biophysics, Stony Brook University, Stony Brook, NY, 11794-8661, United States
| | - Suzanne Scarlata
- Dept of Physiology & Biophysics, Stony Brook University, Stony Brook, NY, 11794-8661, United States; Dept. of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, MA, 01609, United States.
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16
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Choi S, Anderson RA. IQGAP1 is a phosphoinositide effector and kinase scaffold. Adv Biol Regul 2015; 60:29-35. [PMID: 26554303 DOI: 10.1016/j.jbior.2015.10.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 10/05/2015] [Accepted: 10/06/2015] [Indexed: 01/16/2023]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PI4,5P2) is a lipid messenger that regulates a wide variety of cellular functions. The majority of cellular PI4,5P2 is generated by isoforms of the type I phosphatidylinositol phosphate kinases (PIPKI) that are generated from three genes, and each PIPKI isoform has a unique distribution and function in cells. It has been shown that the signaling specificity of PI4,5P2 can be determined by a physical association of PIPKs with PI4,5P2 effectors. IQGAP1 is newly identified as an interactor of multiple isoforms of PIPKs. Considering the versatile roles of IQGAP1 in cellular signaling pathways, IQGAP1 may confer isoform-specific roles of PIPKs in distinct cellular locations. In this mini review, the emerging roles of PIPKs that are regulated by an association with IQGAP1 will be summarized. Focuses will be on cell migration, vesicle trafficking, cell signaling, and nuclear events.
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Affiliation(s)
- Suyong Choi
- University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Richard A Anderson
- University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA.
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17
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Cocco L, Follo MY, Manzoli L, Suh PG. Phosphoinositide-specific phospholipase C in health and disease. J Lipid Res 2015; 56:1853-60. [PMID: 25821234 DOI: 10.1194/jlr.r057984] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Indexed: 12/20/2022] Open
Abstract
Phospholipases are widely occurring and can be found in several different organisms, including bacteria, yeast, plants, animals, and viruses. Phospholipase C (PLC) is a class of phospholipases that cleaves phospholipids on the diacylglycerol (DAG) side of the phosphodiester bond producing DAGs and phosphomonoesters. Among PLCs, phosphoinositide-specific PLC (PI-PLC) constitutes an important step in the inositide signaling pathways. The structures of PI-PLC isozymes show conserved domains as well as regulatory specific domains. This is important, as most PI-PLCs share a common mechanism, but each of them has a peculiar role and can have a specific cell distribution that is linked to a specific function. More importantly, the regulation of PLC isozymes is fundamental in health and disease, as there are several PLC-dependent molecular mechanisms that are associated with the activation or inhibition of important physiopathological processes. Moreover, PI-PLC alternative splicing variants can play important roles in complex signaling networks, not only in cancer but also in other diseases. That is why PI-PLC isozymes are now considered as important molecules that are essential for better understanding the molecular mechanisms underlying both physiology and pathogenesis, and are also potential molecular targets useful for the development of innovative therapeutic strategies.
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Affiliation(s)
- Lucio Cocco
- Cellular Signalling Laboratory, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Matilde Y Follo
- Cellular Signalling Laboratory, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Lucia Manzoli
- Cellular Signalling Laboratory, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Pann-Ghill Suh
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 689-798, Korea
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18
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Milella M, Falcone I, Conciatori F, Cesta Incani U, Del Curatolo A, Inzerilli N, Nuzzo CMA, Vaccaro V, Vari S, Cognetti F, Ciuffreda L. PTEN: Multiple Functions in Human Malignant Tumors. Front Oncol 2015; 5:24. [PMID: 25763354 PMCID: PMC4329810 DOI: 10.3389/fonc.2015.00024] [Citation(s) in RCA: 323] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 01/22/2015] [Indexed: 12/16/2022] Open
Abstract
PTEN is the most important negative regulator of the PI3K signaling pathway. In addition to its canonical, PI3K inhibition-dependent functions, PTEN can also function as a tumor suppressor in a PI3K-independent manner. Indeed, the PTEN network regulates a broad spectrum of biological functions, modulating the flow of information from membrane-bound growth factor receptors to nuclear transcription factors, occurring in concert with other tumor suppressors and oncogenic signaling pathways. PTEN acts through its lipid and protein phosphatase activity and other non-enzymatic mechanisms. Studies conducted over the past 10 years have expanded our understanding of the biological role of PTEN, showing that in addition to its ability to regulate proliferation and cell survival, it also plays an intriguing role in regulating genomic stability, cell migration, stem cell self-renewal, and tumor microenvironment. Changes in PTEN protein levels, location, and enzymatic activity through various molecular mechanisms can generate a continuum of functional PTEN levels in inherited syndromes, sporadic cancers, and other diseases. PTEN activity can indeed, be modulated by mutations, epigenetic silencing, transcriptional repression, aberrant protein localization, and post-translational modifications. This review will discuss our current understanding of the biological role of PTEN, how PTEN expression and activity are regulated, and the consequences of PTEN dysregulation in human malignant tumors.
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Affiliation(s)
- Michele Milella
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Italia Falcone
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Fabiana Conciatori
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Ursula Cesta Incani
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Anais Del Curatolo
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Nicola Inzerilli
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Carmen M A Nuzzo
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Vanja Vaccaro
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Sabrina Vari
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Francesco Cognetti
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
| | - Ludovica Ciuffreda
- Division of Medical Oncology A, Regina Elena National Cancer Institute , Rome , Italy
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19
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Follo MY, Manzoli L, Poli A, McCubrey JA, Cocco L. PLC and PI3K/Akt/mTOR signalling in disease and cancer. Adv Biol Regul 2014; 57:10-6. [PMID: 25482988 DOI: 10.1016/j.jbior.2014.10.004] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 10/22/2014] [Indexed: 12/20/2022]
Abstract
Cancer cell metabolism is deregulated, and signalling pathways can be involved. For instance, PI3K/Akt/mTOR is associated with normal proliferation and differentiation, and its alteration is detectable in cancer cells, that exploit the normal mechanisms to overcome apoptosis. On the other hand, also the family of Phospholipase C (PLC) enzymes play a critical role in cell growth, and any change concerning these enzymes or their downstream targets can be associated with neoplastic transformation. Here, we review the role of PLC and PI3K/Akt/mTOR signal transduction pathways in pathophysiology.
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Affiliation(s)
- Matilde Y Follo
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, University of Bologna, Bologna, Italy.
| | - Lucia Manzoli
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, University of Bologna, Bologna, Italy
| | - Alessandro Poli
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, University of Bologna, Bologna, Italy
| | - James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, USA
| | - Lucio Cocco
- Department of Biomedical and Neuromotor Sciences, Cellular Signalling Laboratory, University of Bologna, Bologna, Italy.
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20
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The signaling phospholipid PIP3 creates a new interaction surface on the nuclear receptor SF-1. Proc Natl Acad Sci U S A 2014; 111:15054-9. [PMID: 25288771 DOI: 10.1073/pnas.1416740111] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The signaling phosphatidylinositol lipids PI(4,5)P2 (PIP2) and PI(3,4,5)P3 (PIP3) bind nuclear receptor 5A family (NR5As), but their regulatory mechanisms remain unknown. Here, the crystal structures of human NR5A1 (steroidogenic factor-1, SF-1) ligand binding domain (LBD) bound to PIP2 and PIP3 show the lipid hydrophobic tails sequestered in the hormone pocket, as predicted. However, unlike classic nuclear receptor hormones, the phosphoinositide head groups are fully solvent-exposed and complete the LBD fold by organizing the receptor architecture at the hormone pocket entrance. The highest affinity phosphoinositide ligand PIP3 stabilizes the coactivator binding groove and increases coactivator peptide recruitment. This receptor-ligand topology defines a previously unidentified regulatory protein-lipid surface on SF-1 with the phosphoinositide head group at its nexus and poised to interact with other proteins. This surface on SF-1 coincides with the predicted binding site of the corepressor DAX-1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region on chromosome X), and importantly harbors missense mutations associated with human endocrine disorders. Our data provide the structural basis for this poorly understood cluster of human SF-1 mutations and demonstrates how signaling phosphoinositides function as regulatory ligands for NR5As.
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21
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Ciuffreda L, Falcone I, Incani UC, Del Curatolo A, Conciatori F, Matteoni S, Vari S, Vaccaro V, Cognetti F, Milella M. PTEN expression and function in adult cancer stem cells and prospects for therapeutic targeting. Adv Biol Regul 2014; 56:66-80. [PMID: 25088603 DOI: 10.1016/j.jbior.2014.07.002] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 07/11/2014] [Indexed: 06/03/2023]
Abstract
Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is a non-redundant lipid phosphatase that restrains and fine tunes the phosphatidylinositol-3-kinase (PI3K) signaling pathway. PTEN is involved in inherited syndromes, which predispose to different types of cancers and is among the most frequently inactivated tumor suppressor genes in sporadic cancers. Indeed, loss of PTEN function occurs in a wide spectrum of human cancers through a variety of mechanisms, including mutations, deletions, transcriptional silencing, or protein instability. PTEN prevents tumorigenesis through multiple mechanisms and regulates a plethora of cellular processes, including survival, proliferation, energy metabolism and cellular architecture. Moreover, recent studies have demonstrated that PTEN is able to exit, exist, and function outside the cell, allowing for inhibition of the PI3K pathway in neighboring cells in a paracrine fashion. Most recently, studies have shown that PTEN is also critical for stem cell maintenance and that PTEN loss can lead to the emergence and proliferation of cancer stem cell (CSC) clones. Depending on the cellular and tissue context of origin, PTEN deletion may result in increased self-renewal capacity or normal stem cell exhaustion and PTEN-defìcient stem and progenitor cells have been reported in prostate, lung, intestinal, and pancreatic tissues before tumor formation; moreover, reversible or irreversible PTEN loss is frequently observed in CSC from a variety of solid and hematologic malignancies, where it may contribute to the functional phenotype of CSC. In this review, we will focus on the role of PTEN expression and function and downstream pathway activation in cancer stem cell biology and regulation of the tumorigenic potential; the emerging role of PTEN in mediating the crosstalk between the PI3K and MAPK pathways will also be discussed, together with prospects for the therapeutic targeting of tumors lacking PTEN expression.
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Affiliation(s)
- Ludovica Ciuffreda
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy.
| | - Italia Falcone
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Ursula Cesta Incani
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Anais Del Curatolo
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Fabiana Conciatori
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Silvia Matteoni
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Sabrina Vari
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Vanja Vaccaro
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Francesco Cognetti
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Michele Milella
- Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
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