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Heitmann T, Liao G, Ernst G, Poslusney M, van Kralingen T, Li Y, Masi M, DePasquale M, Buchler I, Wei H, Carr GV, Shlevkov E, Lu M, Jessen H, Barrow JC. Identification and Characterization of a Blood-Brain Barrier Penetrant Inositol Hexakisphosphate Kinase (IP6K) Inhibitor. J Med Chem 2024. [PMID: 39096294 DOI: 10.1021/acs.jmedchem.4c00190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2024]
Abstract
Inositol hexakisphosphate kinases (IP6Ks) have been studied for their role in glucose homeostasis, metabolic disease, fatty liver disease, chronic kidney disease, neurological development, and psychiatric disease. IP6Ks phosphorylate inositol hexakisphosphate (IP6) to the pyrophosphate, 5-diphosphoinositol-1,2,3,4,6-pentakisphosphate (5-IP7). Most of the currently known potent IP6K inhibitors contain a critical carboxylic acid which limits blood-brain barrier (BBB) penetration. In this work, the synthesis and testing of a variety of carboxylic acid isosteres resulted in several new compounds with improved BBB penetration. The most promising compound has an IP6K1 IC50 of 16 nM with an improved brain/plasma ratio and a favorable pharmacokinetic profile. This series of brain penetrant compounds may be used to investigate the role of IP6Ks in CNS disorders.
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Affiliation(s)
- Tyler Heitmann
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Gangling Liao
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Glen Ernst
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Michael Poslusney
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Thomas van Kralingen
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Ye Li
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Megan Masi
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Michael DePasquale
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Ingrid Buchler
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Huijun Wei
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Gregory V Carr
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Evgeny Shlevkov
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
| | - Mengsi Lu
- Institute of Organic Chemistry and CIBSS─Centre for Integrative Biological Signaling Studies, Albert-Ludwigs-University, Albertstr. 21, Freiburg 79104, Germany
| | - Henning Jessen
- Institute of Organic Chemistry and CIBSS─Centre for Integrative Biological Signaling Studies, Albert-Ludwigs-University, Albertstr. 21, Freiburg 79104, Germany
| | - James C Barrow
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
- Lieber Institute for Brain Development, 855 N. Wolfe Street, Baltimore, Maryland 21205, United States
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2
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Fu L, Du J, Furkert D, Shipton ML, Liu X, Aguirre T, Chin AC, Riley AM, Potter BVL, Fiedler D, Zhang X, Zhu Y, Fu C. Depleting inositol pyrophosphate 5-InsP7 protected the heart against ischaemia-reperfusion injury by elevating plasma adiponectin. Cardiovasc Res 2024; 120:954-970. [PMID: 38252884 PMCID: PMC11218692 DOI: 10.1093/cvr/cvae017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 11/20/2023] [Accepted: 11/30/2023] [Indexed: 01/24/2024] Open
Abstract
AIMS Adiponectin is an adipocyte-derived circulating protein that exerts cardiovascular and metabolic protection. Due to the futile degradation of endogenous adiponectin and the challenges of exogenous administration, regulatory mechanisms of adiponectin biosynthesis are of significant pharmacological interest. METHODS AND RESULTS Here, we report that 5-diphosphoinositol 1,2,3,4,6-pentakisphosphate (5-InsP7) generated by inositol hexakisphosphate kinase 1 (IP6K1) governed circulating adiponectin levels via thiol-mediated protein quality control in the secretory pathway. IP6K1 bound to adiponectin and DsbA-L and generated 5-InsP7 to stabilize adiponectin/ERp44 and DsbA-L/Ero1-Lα interactions, driving adiponectin intracellular degradation. Depleting 5-InsP7 by either IP6K1 deletion or pharmacological inhibition blocked intracellular adiponectin degradation. Whole-body and adipocyte-specific deletion of IP6K1 boosted plasma adiponectin levels, especially its high molecular weight forms, and activated AMPK-mediated protection against myocardial ischaemia-reperfusion injury. Pharmacological inhibition of 5-InsP7 biosynthesis in wild-type but not adiponectin knockout mice attenuated myocardial ischaemia-reperfusion injury. CONCLUSION Our findings revealed that 5-InsP7 is a physiological regulator of adiponectin biosynthesis that is amenable to pharmacological intervention for cardioprotection.
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Affiliation(s)
- Lin Fu
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China
| | - Jimin Du
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China
| | - David Furkert
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Megan L Shipton
- Medicinal Chemistry and Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Xiaoqi Liu
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China
| | - Tim Aguirre
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Alfred C Chin
- Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY, USA
| | - Andrew M Riley
- Medicinal Chemistry and Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Barry V L Potter
- Medicinal Chemistry and Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Dorothea Fiedler
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Xu Zhang
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China
| | - Yi Zhu
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China
| | - Chenglai Fu
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Tianjin Medical University, 22 Qixiangtai Road, Heping District, Tianjin 300070, China
- Institute for Developmental and Regenerative Cardiovascular Medicine, Xinhua Hospital affiliated to Shanghai Jiao Tong University School of Medicine, 1665 Kongjiang Road, Yangpu District, Shanghai 200092, China
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3
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Khan A, Mallick M, Ladke JS, Bhandari R. The ring rules the chain - inositol pyrophosphates and the regulation of inorganic polyphosphate. Biochem Soc Trans 2024; 52:567-580. [PMID: 38629621 DOI: 10.1042/bst20230256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 03/29/2024] [Accepted: 04/03/2024] [Indexed: 04/25/2024]
Abstract
The maintenance of phosphate homeostasis serves as a foundation for energy metabolism and signal transduction processes in all living organisms. Inositol pyrophosphates (PP-InsPs), composed of an inositol ring decorated with monophosphate and diphosphate moieties, and inorganic polyphosphate (polyP), chains of orthophosphate residues linked by phosphoanhydride bonds, are energy-rich biomolecules that play critical roles in phosphate homeostasis. There is a complex interplay between these two phosphate-rich molecules, and they share an interdependent relationship with cellular adenosine triphosphate (ATP) and inorganic phosphate (Pi). In eukaryotes, the enzymes involved in PP-InsP synthesis show some degree of conservation across species, whereas distinct enzymology exists for polyP synthesis among different organisms. In fact, the mechanism of polyP synthesis in metazoans, including mammals, is still unclear. Early studies on PP-InsP and polyP synthesis were conducted in the slime mould Dictyostelium discoideum, but it is in the budding yeast Saccharomyces cerevisiae that a clear understanding of the interplay between polyP, PP-InsPs, and Pi homeostasis has now been established. Recent research has shed more light on the influence of PP-InsPs on polyP in mammals, and the regulation of both these molecules by cellular ATP and Pi levels. In this review we will discuss the cross-talk between PP-InsPs, polyP, ATP, and Pi in the context of budding yeast, slime mould, and mammals. We will also highlight the similarities and differences in the relationship between these phosphate-rich biomolecules among this group of organisms.
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Affiliation(s)
- Azmi Khan
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, India
| | - Manisha Mallick
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, India
- Graduate Studies, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| | - Jayashree S Ladke
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, India
- Graduate Studies, Regional Centre for Biotechnology, Faridabad 121001, Haryana, India
| | - Rashna Bhandari
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, India
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Mihiret YE, Schaaf G, Kamleitner M. Protein pyrophosphorylation by inositol phosphates: a novel post-translational modification in plants? FRONTIERS IN PLANT SCIENCE 2024; 15:1347922. [PMID: 38455731 PMCID: PMC10917965 DOI: 10.3389/fpls.2024.1347922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 02/01/2024] [Indexed: 03/09/2024]
Abstract
Inositol pyrophosphates (PP-InsPs) are energy-rich molecules harboring one or more diphosphate moieties. PP-InsPs are found in all eukaryotes evaluated and their functional versatility is reflected in the various cellular events in which they take part. These include, among others, insulin signaling and intracellular trafficking in mammals, as well as innate immunity and hormone and phosphate signaling in plants. The molecular mechanisms by which PP-InsPs exert such functions are proposed to rely on the allosteric regulation via direct binding to proteins, by competing with other ligands, or by protein pyrophosphorylation. The latter is the focus of this review, where we outline a historical perspective surrounding the first findings, almost 20 years ago, that certain proteins can be phosphorylated by PP-InsPs in vitro. Strikingly, in vitro phosphorylation occurs by an apparent enzyme-independent but Mg2+-dependent transfer of the β-phosphoryl group of an inositol pyrophosphate to an already phosphorylated serine residue at Glu/Asp-rich protein regions. Ribosome biogenesis, vesicle trafficking and transcription are among the cellular events suggested to be modulated by protein pyrophosphorylation in yeast and mammals. Here we discuss the latest efforts in identifying targets of protein pyrophosphorylation, pointing out the methodological challenges that have hindered the full understanding of this unique post-translational modification, and focusing on the latest advances in mass spectrometry that finally provided convincing evidence that PP-InsP-mediated pyrophosphorylation also occurs in vivo. We also speculate about the relevance of this post-translational modification in plants in a discussion centered around the protein kinase CK2, whose activity is critical for pyrophosphorylation of animal and yeast proteins. This enzyme is widely present in plant species and several of its functions overlap with those of PP-InsPs. Until now, there is virtually no data on pyrophosphorylation of plant proteins, which is an exciting field that remains to be explored.
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Affiliation(s)
| | | | - Marília Kamleitner
- Department of Plant Nutrition, Institute of Crop Science and Resource Conservation, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
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5
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Heitmann T, Liao G, de León P, Ernst G, Buchler I, Wei H, Shlevkov E, Brown D, Fitzek M, Collier M, Smith DM, Barrow JC. Fragment-Based Screening Identifies New Quinazolinone-Based Inositol Hexakisphosphate Kinase (IP6K) Inhibitors. ACS Med Chem Lett 2023; 14:1760-1766. [PMID: 38116421 PMCID: PMC10726443 DOI: 10.1021/acsmedchemlett.3c00409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/15/2023] [Accepted: 11/17/2023] [Indexed: 12/21/2023] Open
Abstract
A high-throughput fragment-based screen has been employed to discover a series of quinazolinone inositol hexakisphosphate kinase (IP6K) inhibitors. IP6Ks have been studied for their role in glucose homeostasis, metabolic disease, fatty liver disease, chronic kidney disease, blood coagulation, neurological development, and psychiatric disease. IP6Ks phosphorylate inositol hexakisphosphate (IP6) to form pyrophosphate 5-diphospho-1,2,3,4,6-pentakisphosphate (IP7). Molecular docking studies and investigation of structure-activity relationships around the quinazolinone core resulted in compounds with submicromolar potency and interesting selectivity for IP6K1 versus the closely related IP6K2 and IP6K3 isoforms.
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Affiliation(s)
- Tyler Heitmann
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Gangling Liao
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Pablo de León
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Glen Ernst
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Ingrid Buchler
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Huijun Wei
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
- Department
of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Evgeny Shlevkov
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Dean Brown
- Hit
Discovery, Discovery Sciences, R&D, AstraZeneca, Boston, Massachusetts 02451, United States
| | - Martina Fitzek
- Hit
Discovery, Discovery Sciences, R&D, AstraZeneca, Alderley Park, Macclesfield SK10 4TG, U.K.
| | - Matthew Collier
- Hit
Discovery, Discovery Sciences, R&D, AstraZeneca, Alderley Park, Macclesfield SK10 4TG, U.K.
| | - David M. Smith
- Emerging
Innovations Unit, Discovery Sciences, R&D, AstraZeneca, Cambridge CB2 0AA, U.K.
| | - James C. Barrow
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
- Department
of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
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6
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Heitmann T, Barrow JC. The Role of Inositol Hexakisphosphate Kinase in the Central Nervous System. Biomolecules 2023; 13:1317. [PMID: 37759717 PMCID: PMC10526494 DOI: 10.3390/biom13091317] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/23/2023] [Accepted: 08/26/2023] [Indexed: 09/29/2023] Open
Abstract
Inositol is a unique biological small molecule that can be phosphorylated or even further pyrophosphorylated on each of its six hydroxyl groups. These numerous phosphorylation states of inositol along with the kinases and phosphatases that interconvert them comprise the inositol phosphate signaling pathway. Inositol hexakisphosphate kinases, or IP6Ks, convert the fully mono-phosphorylated inositol to the pyrophosphate 5-IP7 (also denoted IP7). There are three isoforms of IP6K: IP6K1, 2, and 3. Decades of work have established a central role for IP6Ks in cell signaling. Genetic and pharmacologic manipulation of IP6Ks in vivo and in vitro has shown their importance in metabolic disease, chronic kidney disease, insulin signaling, phosphate homeostasis, and numerous other cellular and physiologic processes. In addition to these peripheral processes, a growing body of literature has shown the role of IP6Ks in the central nervous system (CNS). IP6Ks have a key role in synaptic vesicle regulation, Akt/GSK3 signaling, neuronal migration, cell death, autophagy, nuclear translocation, and phosphate homeostasis. IP6Ks' regulation of these cellular processes has functional implications in vivo in behavior and CNS anatomy.
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Affiliation(s)
- Tyler Heitmann
- Department of Pharmacology and Molecular Sciences, School of Medicine, Johns Hopkins University, 725 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
- The Lieber Institute for Brain Development, 855 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
| | - James C. Barrow
- Department of Pharmacology and Molecular Sciences, School of Medicine, Johns Hopkins University, 725 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
- The Lieber Institute for Brain Development, 855 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
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High-Throughput Sequencing Reveals That Rotundine Inhibits Colorectal Cancer by Regulating Prognosis-Related Genes. J Pers Med 2023; 13:jpm13030550. [PMID: 36983731 PMCID: PMC10052610 DOI: 10.3390/jpm13030550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 03/22/2023] Open
Abstract
Background: Rotundine is an herbal medicine with anti-cancer effects. However, little is known about the anti-cancer effect of rotundine on colorectal cancer. Therefore, our study aimed to investigate the specific molecular mechanism of rotundine inhibition of colorectal cancer. Methods: MTT and cell scratch assay were performed to investigate the effects of rotundine on the viability, migration, and invasion ability of SW480 cells. Changes in cell apoptosis were analyzed by flow cytometry. DEGs were detected by high-throughput sequencing after the action of rotundine on SW480 cells, and the DEGs were subjected to function enrichment analysis. Bioinformatics analyses were performed to screen out prognosis-related DEGs of COAD. Followed by enrichment analysis of prognosis-related DEGs. Furthermore, prognostic models were constructed, including ROC analysis, risk curve analysis, PCA and t-SNE, Nomo analysis, and Kaplan–Meier prognostic analysis. Results: In this study, we showed that rotundine concentrations of 50 μM, 100 μM, 150 μM, and 200 μM inhibited the proliferation, migration, and invasion of SW480 cells in a time- and concentration-dependent manner. Rotundine does not induce SW480 cell apoptosis. Compared to the control group, high-throughput results showed that there were 385 DEGs in the SW480 group. And DEGs were associated with the Hippo signaling pathway. In addition, 16 of the DEGs were significantly associated with poorer prognosis in COAD, with MEF2B, CCDC187, PSD2, RGS16, PLXDC1, HELB, ASIC3, PLCH2, IGF2BP3, CLHC1, DNHD1, SACS, H1-4, ANKRD36, and ZNF117 being highly expressed in COAD and ARV1 being lowly expressed. Prognosis-related DEGs were mainly enriched in cancer-related pathways and biological functions, such as inositol phosphate metabolism, enterobactin transmembrane transporter activity, and enterobactin transport. Prognostic modeling also showed that these 16 DEGs could be used as predictors of overall survival prognosis in COAD patients. Conclusions: Rotundine inhibits the development and progression of colorectal cancer by regulating the expression of these prognosis-related genes. Our findings could further provide new directions for the treatment of colorectal cancer.
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Blocking Polyphosphate Mobilization Inhibits Pho4 Activation and Virulence in the Pathogen Candida albicans. mBio 2022; 13:e0034222. [PMID: 35575514 PMCID: PMC9239153 DOI: 10.1128/mbio.00342-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The ability of pathogenic fungi to obtain essential nutrients from the host is vital for virulence. In Candida albicans, acquisition of the macronutrient phosphate is regulated by the Pho4 transcription factor and is important for both virulence and resistance to host-encountered stresses. All cells store phosphate in the form of polyphosphate (polyP), a ubiquitous polymer comprising tens to hundreds of phosphate residues. Release of phosphate from polyP is one of the first responses evoked in response to phosphate starvation, and here, we sought to explore the importance of polyP mobilization in the pathobiology of C. albicans. We found that two polyphosphatases, Ppn1 and Ppx1, function redundantly to release phosphate from polyP in C. albicans. Strikingly, we reveal that blocking polyP mobilization prevents the activation of the Pho4 transcription factor: following Pi starvation, Pho4 fails to accumulate in the nucleus and induce Pi acquisition genes in ppn1Δ ppx1Δ cells. Consequently, ppn1Δ ppx1Δ cells display impaired resistance to the same range of stresses that require Pho4 for survival. In addition, cells lacking both polyphosphatases are exquisitely sensitive to DNA replication stress, indicating that polyP mobilization is needed to support the phosphate-demanding process of DNA replication. Blocking polyP mobilization also results in significant morphological defects, as ppn1Δ ppx1Δ cells form large pseudohypha-like cells that are resistant to serum-induced hypha formation. Thus, polyP mobilization impacts key processes important for the pathobiology of C. albicans, and consistent with this, we found that blocking this process attenuates the virulence of this important human fungal pathogen.
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9
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Nagpal L, Kornberg MD, Snyder SH. Inositol hexakisphosphate kinase-2 non-catalytically regulates mitophagy by attenuating PINK1 signaling. Proc Natl Acad Sci U S A 2022; 119:e2121946119. [PMID: 35353626 PMCID: PMC9169102 DOI: 10.1073/pnas.2121946119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 02/08/2022] [Indexed: 11/18/2022] Open
Abstract
Inositol pyrophosphates, such as 5-diphosphoinositol pentakisphosphate (IP7), are generated by a family of inositol hexakisphosphate kinases (IP6Ks), of which IP6K2 has been implicated in various cellular functions including neuroprotection. Absence of IP6K2 causes impairment of oxidative phosphorylation regulated by creatine kinase-B. In the present study, we show that IP6K2 is involved in attenuation of PINK1-mediated mitochondrial autophagy (mitophagy) in the brain. Up-regulation of dynamin-related protein (Drp-1), as well as increased expression of mitochondrial biogenesis markers (PGC1-α and NRF-1) in the cerebella of IP6K2-deleted mice (IP6K2-knockout), point to the involvement of IP6K2 in the regulation of mitochondrial fission. Knockdown of IP6K2 also leads to augmented glycolysis, potentially as a compensatory mechanism for decreased mitochondrial respiration. Overexpressing IP6K2 as well as IP6K2-kinase dead mutant in IP6K2-knockdown N2A cells reverses the expression of mitophagy markers, demonstrating that IP6K2-induced mitoprotection is catalytically/kinase independent. IP6K2 supplementation in K2-PINK1 double-knockdown N2A cells fails to reverse the expression of the mitophagic marker, LC3-II, indicating that the mitoprotective effect of IP6K2 is dependent on PINK1. Overall, our study reveals a key neuroprotective role of IP6K2 in the prevention of PINK1-mediated mitophagy in the brain.
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Affiliation(s)
- Latika Nagpal
- The Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Michael D. Kornberg
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD 21287
| | - Solomon H. Snyder
- The Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD 21205
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21287
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21205
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Whole Body Ip6k1 Deletion Protects Mice from Age-Induced Weight Gain, Insulin Resistance and Metabolic Dysfunction. Int J Mol Sci 2022; 23:ijms23042059. [PMID: 35216174 PMCID: PMC8878859 DOI: 10.3390/ijms23042059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/05/2022] [Accepted: 02/10/2022] [Indexed: 12/21/2022] Open
Abstract
(1) Background: We previously demonstrated that disruption of IP6K1 improves metabolism, protecting mice from high-fat diet-induced obesity, insulin resistance, and non-alcoholic fatty liver disease and steatohepatitis. Age-induced metabolic dysfunction is a major risk factor for metabolic diseases. The involvement of IP6K1 in this process is unknown. (2) Methods: Here, we compared body and fat mass, insulin sensitivity, energy expenditure and serum-, adipose tissue- and liver-metabolic parameters of chow-fed, aged, wild type (aWT) and whole body Ip6k1 knockout (aKO) mice. (3) Results: IP6K1 was upregulated in the adipose tissue and liver of aWT mice compared to young WT mice. Moreover, Ip6k1 deletion blocked age-induced increase in body- and fat-weight and insulin resistance in mice. aKO mice oxidized carbohydrates more efficiently. The knockouts displayed reduced levels of serum insulin, triglycerides, and non-esterified fatty acids. Ip6k1 deletion partly protected age-induced decline of the thermogenic uncoupling protein UCP1 in inguinal white adipose tissue. Targets inhibited by IP6K1 activity such as the insulin sensitivity- and energy expenditure-inducing protein kinases, protein kinase B (PKB/Akt) and AMP-activated protein kinase (AMPK), were activated in the adipose tissue and liver of aKO mice. (4) Conclusions: Ip6k1 deletion maintains healthy metabolism in aging and thus, targeting this kinase may delay the development of age-induced metabolic dysfunction.
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11
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Isomer-selective analysis of inositol phosphates with differential isotope labelling by phosphate methylation using liquid chromatography with tandem mass spectrometry. Anal Chim Acta 2022; 1191:339286. [PMID: 35033253 DOI: 10.1016/j.aca.2021.339286] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/08/2021] [Accepted: 11/14/2021] [Indexed: 11/21/2022]
Abstract
Inositol phosphates belong to a family of structurally diverse signaling molecules playing crucial role in Ca2+ release from intracellular storage vesicles. There are many possibilities of phosphorylation, including their degree and position. Inositol (1,4,5) trisphosphate has been well recognized as the most important second messenger among this family. It remains a challenge to analyse the entire inositol phosphate metabolite family due to its structural complexity, high polarity, and high phosphate density. In this study, we have established an improved UHPLC-ESI-MS/MS method based on a differential isotope labelling methylation strategy. An SPE extraction kit composed of TiO2 and PTFE filter was employed for sample preparation which provided good extraction performance. Samples were methylated (light label) to neutralize the phosphate groups and give better performance in liquid chromatography. Regioisomers and inositol phosphates differing in their number of phosphate residues were successfully separated after optimization on a core-shell cholesterylether-bonded RP-type column (Cosmocore 2.6Cholester) using methanol as organic modifier. Triple quadrupole MS detection was based on selected reaction monitoring (SRM) acquisition with characteristic fragments. Stable isotope labeling methylation was performed to generate internal standards (heavy label). Limits of quantification from 0.32 to 0.89 pmol on column was achieved. This method was validated to be suitable for inositol phosphate profiling in biological samples. After application in cultured HeLa cells, NIST SRM1950 plasma, and human platelets, distinct inositol profiles were obtained. This newly established method exhibited improved analytical performance, holding the potential to advance the understanding of inositol phosphate signaling.
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12
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Wang Z, Kuo HF, Chiou TJ. Intracellular phosphate sensing and regulation of phosphate transport systems in plants. PLANT PHYSIOLOGY 2021; 187:2043-2055. [PMID: 35235674 PMCID: PMC8644344 DOI: 10.1093/plphys/kiab343] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/29/2021] [Indexed: 05/04/2023]
Abstract
Recent research on the regulation of cellular phosphate (Pi) homeostasis in eukaryotes has collectively made substantial advances in elucidating inositol pyrophosphates (PP-InsP) as Pi signaling molecules that are perceived by the SPX (Syg1, Pho81, and Xpr1) domains residing in multiple proteins involved in Pi transport and signaling. The PP-InsP-SPX signaling module is evolutionarily conserved across eukaryotes and has been elaborately adopted in plant Pi transport and signaling systems. In this review, we have integrated these advances with prior established knowledge of Pi and PP-InsP metabolism, intracellular Pi sensing, and transcriptional responses according to the dynamics of cellular Pi status in plants. Anticipated challenges and pending questions as well as prospects are also discussed.
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Affiliation(s)
- Zhengrui Wang
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Hui-Fen Kuo
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Tzyy-Jen Chiou
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
- Author for communication:
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13
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Mukherjee S, Chakraborty M, Ulmasov B, McCommis K, Zhang J, Carpenter D, Msengi EN, Haubner J, Guo C, Pike DP, Ghoshal S, Ford DA, Neuschwander-Tetri BA, Chakraborty A. Pleiotropic actions of IP6K1 mediate hepatic metabolic dysfunction to promote nonalcoholic fatty liver disease and steatohepatitis. Mol Metab 2021; 54:101364. [PMID: 34757046 PMCID: PMC8609165 DOI: 10.1016/j.molmet.2021.101364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/11/2021] [Accepted: 10/23/2021] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE Obesity and insulin resistance greatly increase the risk of nonalcoholic fatty liver disease and steatohepatitis (NAFLD/NASH). We have previously discovered that whole-body and adipocyte-specific Ip6k1deletion protects mice from high-fat-diet-induced obesity and insulin resistance due to improved adipocyte thermogenesis and insulin signaling. Here, we aimed to determine the impact of hepatocyte-specific and whole-body Ip6k1 deletion (HKO and Ip6k1-KO or KO) on liver metabolism and NAFLD/NASH. METHODS Body weight and composition; energy expenditure; glycemic profiles; and serum and liver metabolic, inflammatory, fibrotic and toxicity parameters were assessed in mice fed Western and high-fructose diet (HFrD) (WD: 40% kcal fat, 1.25% cholesterol, no added choline and HFrD: 60% kcal fructose). Mitochondrial oxidative capacity was evaluated in isolated hepatocytes. RNA-Seq was performed in liver samples. Livers from human NASH patients were analyzed by immunoblotting and mass spectrometry. RESULTS HKO mice displayed increased hepatocyte mitochondrial oxidative capacity and improved insulin sensitivity but were not resistant to body weight gain. Improved hepatocyte metabolism partially protected HKO mice from NAFLD/NASH. In contrast, enhanced whole-body metabolism and reduced body fat accumulation significantly protected whole-body Ip6k1-KO mice from NAFLD/NASH. Mitochondrial oxidative pathways were upregulated, whereas gluconeogenic and fibrogenic pathways were downregulated in Ip6k1-KO livers. Furthermore, IP6K1 was upregulated in human NASH livers and interacted with the enzyme O-GlcNAcase that reduces protein O-GlcNAcylation. Protein O-GlcNAcylation was found to be reduced in Ip6k1-KO and HKO mouse livers. CONCLUSION Pleiotropic actions of IP6K1 in the liver and other metabolic tissues mediate hepatic metabolic dysfunction and NAFLD/NASH, and thus IP6K1 deletion may be a potential treatment target for this disease.
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Affiliation(s)
- Sandip Mukherjee
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Molee Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Barbara Ulmasov
- Division of Gastroenterology and Hepatology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Kyle McCommis
- Department of Biochemistry, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Jinsong Zhang
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Danielle Carpenter
- Department of Pathology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Eliwaza Naomi Msengi
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Jake Haubner
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Chun Guo
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Daniel P Pike
- Department of Biochemistry, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Sarbani Ghoshal
- Department of Biological Sc. and Geology, QCC-CUNY, Bayside, NY, USA
| | - David A Ford
- Department of Biochemistry, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Brent A Neuschwander-Tetri
- Division of Gastroenterology and Hepatology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Anutosh Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA.
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14
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Zhang X, Li N, Zhang J, Zhang Y, Yang X, Luo Y, Zhang B, Xu Z, Zhu Z, Yang X, Yan Y, Lin B, Wang S, Chen D, Ye C, Ding Y, Lou M, Wu Q, Hou Z, Zhang K, Liang Z, Wei A, Wang B, Wang C, Jiang N, Zhang W, Xiao G, Ma C, Ren Y, Qi X, Han W, Wang C, Rao F. 5-IP 7 is a GPCR messenger mediating neural control of synaptotagmin-dependent insulin exocytosis and glucose homeostasis. Nat Metab 2021; 3:1400-1414. [PMID: 34663975 DOI: 10.1038/s42255-021-00468-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 09/02/2021] [Indexed: 11/08/2022]
Abstract
5-diphosphoinositol pentakisphosphate (5-IP7) is a signalling metabolite linked to various cellular processes. How extracellular stimuli elicit 5-IP7 signalling remains unclear. Here we show that 5-IP7 in β cells mediates parasympathetic stimulation of synaptotagmin-7 (Syt7)-dependent insulin release. Mechanistically, vagal stimulation and activation of muscarinic acetylcholine receptors triggers Gαq-PLC-PKC-PKD-dependent signalling and activates IP6K1, the 5-IP7 synthase. Whereas both 5-IP7 and its precursor IP6 compete with PIP2 for binding to Syt7, Ca2+ selectively binds 5-IP7 with high affinity, freeing Syt7 to enable fusion of insulin-containing vesicles with the cell membrane. β-cell-specific IP6K1 deletion diminishes insulin secretion and glucose clearance elicited by muscarinic stimulation, whereas mice carrying a phosphorylation-mimicking, hyperactive IP6K1 mutant display augmented insulin release, congenital hyperinsulinaemia and obesity. These phenotypes are absent in mice lacking Syt7. Our study proposes a new conceptual framework for inositol pyrophosphate physiology in which 5-IP7 acts as a GPCR second messenger at the interface between peripheral nervous system and metabolic organs, transmitting Gq-coupled GPCR stimulation to unclamp Syt7-dependent, and perhaps other, exocytotic events.
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Affiliation(s)
- Xiaozhe Zhang
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Na Li
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Jun Zhang
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Yanshen Zhang
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Department of Neurology, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Xiaoli Yang
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Yifan Luo
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Bobo Zhang
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Zhixue Xu
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Zhenhua Zhu
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Xiuyan Yang
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Yuan Yan
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Biao Lin
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China
| | - Shen Wang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Da Chen
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Department of Neurology, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Caichao Ye
- Department of Physics and Shenzhen Institute for Quantum Science & Technology, Southern University of Science and Technology, Shenzhen, China
| | - Yan Ding
- National Institute of Biological Sciences, Beijing, China
| | - Mingliang Lou
- National Institute of Biological Sciences, Beijing, China
| | - Qingcui Wu
- National Institute of Biological Sciences, Beijing, China
| | - Zhanfeng Hou
- National Institute of Biological Sciences, Beijing, China
| | - Keren Zhang
- BGI-Shenzhen, Beishan Industrial Zone 11th building, Shenzhen, China
| | - Ziming Liang
- Department of Hepatic Surgery, the Third People's Hospital of Shenzhen and the Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, China
| | - Anqi Wei
- Neuroscience Research Center, Institute of Mitochondrial Biology and Medicine, Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Bianbian Wang
- Neuroscience Research Center, Institute of Mitochondrial Biology and Medicine, Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Changhe Wang
- Neuroscience Research Center, Institute of Mitochondrial Biology and Medicine, Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Nan Jiang
- Department of Hepatic Surgery, the Third People's Hospital of Shenzhen and the Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, China
| | - Wenqing Zhang
- Department of Physics and Shenzhen Institute for Quantum Science & Technology, Southern University of Science and Technology, Shenzhen, China
| | - Guozhi Xiao
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, China
| | - Cong Ma
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Yan Ren
- BGI-Shenzhen, Beishan Industrial Zone 11th building, Shenzhen, China
| | - Xiangbing Qi
- National Institute of Biological Sciences, Beijing, China
| | - Weiping Han
- Institute of Molecular and Cell Biology, Agency for Science, Technology, and Research, Singapore, Singapore
- Center for Neuro-Metabolism and Regeneration Research, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Chao Wang
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
- Department of Neurology, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
| | - Feng Rao
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China.
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15
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Inositol hexakisphosphate kinase-2 determines cellular energy dynamics by regulating creatine kinase-B. Proc Natl Acad Sci U S A 2021; 118:2020695118. [PMID: 33547244 DOI: 10.1073/pnas.2020695118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Inositol hexakisphosphate kinases (IP6Ks) regulate various biological processes. IP6Ks convert IP6 to pyrophosphates such as diphosphoinositol pentakisphosphate (IP7) and bis-diphosphoinositol tetrakisphosphate (IP8). IP7 is produced in mammals by a family of inositol hexakisphosphate kinases, IP6K1, IP6K2, and IP6K3, which have distinct biological functions. The inositol hexakisphosphate kinase 2 (IP6K2) controls cellular apoptosis. To explore roles for IP6K2 in brain function, we elucidated its protein interactome in mouse brain revealing a robust association of IP6K2 with creatine kinase-B (CK-B), a key enzyme in energy homeostasis. Cerebella of IP6K2-deleted mice (IP6K2-knockout [KO]) produced less phosphocreatine and ATP and generated higher levels of reactive oxygen species and protein oxidative damage. In IP6K2-KO mice, mitochondrial dysfunction was associated with impaired expression of the cytochrome-c1 subunit of complex III of the electron transport chain. We reversed some of these effects by combined treatment with N-acetylcysteine and phosphocreatine. These findings establish a role for IP6K2-CK-B interaction in energy homeostasis associated with neuroprotection.
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16
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Márquez-Moñino MÁ, Ortega-García R, Shipton ML, Franco-Echevarría E, Riley AM, Sanz-Aparicio J, Potter BVL, González B. Multiple substrate recognition by yeast diadenosine and diphosphoinositol polyphosphate phosphohydrolase through phosphate clamping. SCIENCE ADVANCES 2021; 7:7/17/eabf6744. [PMID: 33893105 PMCID: PMC8064635 DOI: 10.1126/sciadv.abf6744] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/04/2021] [Indexed: 06/12/2023]
Abstract
The yeast diadenosine and diphosphoinositol polyphosphate phosphohydrolase DDP1 is a Nudix enzyme with pyrophosphatase activity on diphosphoinositides, dinucleotides, and polyphosphates. These substrates bind to diverse protein targets and participate in signaling and metabolism, being essential for energy and phosphate homeostasis, ATPase pump regulation, or protein phosphorylation. An exhaustive structural study of DDP1 in complex with multiple ligands related to its three diverse substrate classes is reported. This allowed full characterization of the DDP1 active site depicting the molecular basis for endowing multisubstrate abilities to a Nudix enzyme, driven by phosphate anchoring following a defined path. This study, combined with multiple enzyme variants, reveals the different substrate binding modes, preferences, and selection. Our findings expand current knowledge on this important structural superfamily with implications extending beyond inositide research. This work represents a valuable tool for inhibitor/substrate design for ScDDP1 and orthologs as potential targets to address fungal infections and other health concerns.
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Affiliation(s)
- María Ángeles Márquez-Moñino
- Department of Crystallography and Structural Biology, Institute of Physical-Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Raquel Ortega-García
- Department of Crystallography and Structural Biology, Institute of Physical-Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Megan L Shipton
- Drug Discovery and Medicinal Chemistry, Department of Pharmacology, University of Oxford Mansfield Road, Oxford OX1 3QT, UK
| | - Elsa Franco-Echevarría
- Department of Crystallography and Structural Biology, Institute of Physical-Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Andrew M Riley
- Drug Discovery and Medicinal Chemistry, Department of Pharmacology, University of Oxford Mansfield Road, Oxford OX1 3QT, UK
| | - Julia Sanz-Aparicio
- Department of Crystallography and Structural Biology, Institute of Physical-Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Barry V L Potter
- Drug Discovery and Medicinal Chemistry, Department of Pharmacology, University of Oxford Mansfield Road, Oxford OX1 3QT, UK
| | - Beatriz González
- Department of Crystallography and Structural Biology, Institute of Physical-Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain.
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17
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Weinberg SE, Sun LY, Yang AL, Liao J, Yang GY. Overview of Inositol and Inositol Phosphates on Chemoprevention of Colitis-Induced Carcinogenesis. Molecules 2020; 26:E31. [PMID: 33374769 PMCID: PMC7796135 DOI: 10.3390/molecules26010031] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 12/18/2020] [Accepted: 12/20/2020] [Indexed: 12/17/2022] Open
Abstract
Chronic inflammation is one of the most common and well-recognized risk factors for human cancer, including colon cancer. Inflammatory bowel disease (IBD) is defined as a longstanding idiopathic chronic active inflammatory process in the colon, including ulcerative colitis and Crohn's disease. Importantly, patients with IBD have a significantly increased risk for the development of colorectal carcinoma. Dietary inositol and its phosphates, as well as phospholipid derivatives, are well known to benefit human health in diverse pathologies including cancer prevention. Inositol phosphates including InsP3, InsP6, and other pyrophosphates, play important roles in cellular metabolic and signal transduction pathways involved in the control of cell proliferation, differentiation, RNA export, DNA repair, energy transduction, ATP regeneration, and numerous others. In the review, we highlight the biologic function and health effects of inositol and its phosphates including the nature and sources of these molecules, potential nutritional deficiencies, their biologic metabolism and function, and finally, their role in the prevention of colitis-induced carcinogenesis.
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Affiliation(s)
- Samuel E. Weinberg
- Department of Pathology, Northwestern University Feinberg School of Medicine, 303 East Chicago Avenue, Chicago, IL 60611, USA; (S.E.W.); (L.Y.S.); (J.L.)
| | - Le Yu Sun
- Department of Pathology, Northwestern University Feinberg School of Medicine, 303 East Chicago Avenue, Chicago, IL 60611, USA; (S.E.W.); (L.Y.S.); (J.L.)
| | - Allison L. Yang
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, 1293 York Avenue, New York, NY 10065, USA;
| | - Jie Liao
- Department of Pathology, Northwestern University Feinberg School of Medicine, 303 East Chicago Avenue, Chicago, IL 60611, USA; (S.E.W.); (L.Y.S.); (J.L.)
| | - Guang Yu Yang
- Department of Pathology, Northwestern University Feinberg School of Medicine, 303 East Chicago Avenue, Chicago, IL 60611, USA; (S.E.W.); (L.Y.S.); (J.L.)
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18
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Chin AC, Gao Z, Riley AM, Furkert D, Wittwer C, Dutta A, Rojas T, Semenza ER, Felder RA, Pluznick JL, Jessen HJ, Fiedler D, Potter BVL, Snyder SH, Fu C. The inositol pyrophosphate 5-InsP 7 drives sodium-potassium pump degradation by relieving an autoinhibitory domain of PI3K p85α. SCIENCE ADVANCES 2020; 6:6/44/eabb8542. [PMID: 33115740 PMCID: PMC7608788 DOI: 10.1126/sciadv.abb8542] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 09/14/2020] [Indexed: 05/10/2023]
Abstract
Sodium/potassium-transporting adenosine triphosphatase (Na+/K+-ATPase) is one of the most abundant cell membrane proteins and is essential for eukaryotes. Endogenous negative regulators have long been postulated to play an important role in regulating the activity and stability of Na+/K+-ATPase, but characterization of these regulators has been elusive. Mechanisms of regulating Na+/K+-ATPase homeostatic turnover are unknown. Here, we report that 5-diphosphoinositol 1,2,3,4,6-pentakisphosphate (5-InsP7), generated by inositol hexakisphosphate kinase 1 (IP6K1), promotes physiological endocytosis and downstream degradation of Na+/K+-ATPase-α1. Deletion of IP6K1 elicits a twofold enrichment of Na+/K+-ATPase-α1 in plasma membranes of multiple tissues and cell types. Using a suite of synthetic chemical biology tools, we found that 5-InsP7 binds the RhoGAP domain of phosphatidylinositol 3-kinase (PI3K) p85α to disinhibit its interaction with Na+/K+-ATPase-α1. This recruits adaptor protein 2 (AP2) and triggers the clathrin-mediated endocytosis of Na+/K+-ATPase-α1. Our study identifies 5-InsP7 as an endogenous negative regulator of Na+/K+-ATPase-α1.
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Affiliation(s)
- Alfred C Chin
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zhe Gao
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, Tianjin, China
| | - Andrew M Riley
- Medicinal Chemistry and Drug Discovery, Department of Pharmacology, University of Oxford, Oxford, UK
| | - David Furkert
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Christopher Wittwer
- Institute of Organic Chemistry and CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, D-79104 Freiburg, Germany
| | - Amit Dutta
- Institute of Organic Chemistry and CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, D-79104 Freiburg, Germany
| | - Tomas Rojas
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Evan R Semenza
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robin A Felder
- Department of Pathology, University of Virginia, Charlottesville, VA, USA
| | - Jennifer L Pluznick
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Henning J Jessen
- Institute of Organic Chemistry and CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, D-79104 Freiburg, Germany
| | - Dorothea Fiedler
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Barry V L Potter
- Medicinal Chemistry and Drug Discovery, Department of Pharmacology, University of Oxford, Oxford, UK
| | - Solomon H Snyder
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Chenglai Fu
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China.
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, Tianjin, China
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19
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Minini M, Senni A, Unfer V, Bizzarri M. The Key Role of IP 6K: A Novel Target for Anticancer Treatments? Molecules 2020; 25:molecules25194401. [PMID: 32992691 PMCID: PMC7583815 DOI: 10.3390/molecules25194401] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 12/29/2022] Open
Abstract
Inositol and its phosphate metabolites play a pivotal role in several biochemical pathways and gene expression regulation: inositol pyrophosphates (PP-IPs) have been increasingly appreciated as key signaling modulators. Fluctuations in their intracellular levels hugely impact the transfer of phosphates and the phosphorylation status of several target proteins. Pharmacological modulation of the proteins associated with PP-IP activities has proved to be beneficial in various pathological settings. IP7 has been extensively studied and found to play a key role in pathways associated with PP-IP activities. Three inositol hexakisphosphate kinase (IP6K) isoforms regulate IP7 synthesis in mammals. Genomic deletion or enzymic inhibition of IP6K1 has been shown to reduce cell invasiveness and migration capacity, protecting against chemical-induced carcinogenesis. IP6K1 could therefore be a useful target in anticancer treatment. Here, we summarize the current understanding that established IP6K1 and the other IP6K isoforms as possible targets for cancer therapy. However, it will be necessary to determine whether pharmacological inhibition of IP6K is safe enough to begin clinical study. The development of safe and selective inhibitors of IP6K isoforms is required to minimize undesirable effects.
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Affiliation(s)
- Mirko Minini
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy;
- Department of Surgery ‘P. Valdoni’, Sapienza University of Rome, 00161 Rome, Italy
- Systems Biology Group Lab, Sapienza University of Rome, 00185 Rome, Italy;
- Correspondence: (M.M.); (M.B.)
| | - Alice Senni
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy;
- Department of Surgery ‘P. Valdoni’, Sapienza University of Rome, 00161 Rome, Italy
| | - Vittorio Unfer
- Systems Biology Group Lab, Sapienza University of Rome, 00185 Rome, Italy;
| | - Mariano Bizzarri
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy;
- Systems Biology Group Lab, Sapienza University of Rome, 00185 Rome, Italy;
- Correspondence: (M.M.); (M.B.)
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Furkert D, Hostachy S, Nadler-Holly M, Fiedler D. Triplexed Affinity Reagents to Sample the Mammalian Inositol Pyrophosphate Interactome. Cell Chem Biol 2020; 27:1097-1108.e4. [PMID: 32783964 DOI: 10.1016/j.chembiol.2020.07.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 06/19/2020] [Accepted: 07/22/2020] [Indexed: 11/15/2022]
Abstract
The inositol pyrophosphates (PP-InsPs) are a ubiquitous group of highly phosphorylated eukaryotic messengers. They have been linked to a panoply of central cellular processes, but a detailed understanding of the discrete signaling events is lacking in most cases. To create a more mechanistic picture of PP-InsP signaling, we sought to annotate the mammalian interactome of the most abundant inositol pyrophosphate 5PP-InsP5. To do so, triplexed affinity reagents were developed, in which a metabolically stable PP-InsP analog was immobilized in three different ways. Application of these triplexed reagents to mammalian lysates identified between 300 and 400 putative interacting proteins. These interactomes revealed connections between 5PP-InsP5 and central cellular regulators, such as lipid phosphatases, protein kinases, and GTPases, and identified protein domains commonly targeted by 5PP-InsP5. Both the triplexed affinity reagents, and the proteomic datasets, constitute powerful resources for the community, to launch future investigations into the multiple signaling modalities of inositol pyrophosphates.
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Affiliation(s)
- David Furkert
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany; Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Sarah Hostachy
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Michal Nadler-Holly
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Dorothea Fiedler
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany; Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany.
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21
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Inositol Pyrophosphates: Signaling Molecules with Pleiotropic Actions in Mammals. Molecules 2020; 25:molecules25092208. [PMID: 32397291 PMCID: PMC7249018 DOI: 10.3390/molecules25092208] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/01/2020] [Accepted: 05/07/2020] [Indexed: 02/07/2023] Open
Abstract
Inositol pyrophosphates (PP-IPs) such as 5-diphosphoinositol pentakisphosphate (5-IP7) are inositol metabolites containing high-energy phosphoanhydride bonds. Biosynthesis of PP-IPs is mediated by IP6 kinases (IP6Ks) and PPIP5 kinases (PPIP5Ks), which transfer phosphate to inositol hexakisphosphate (IP6). Pleiotropic actions of PP-IPs are involved in many key biological processes, including growth, vesicular remodeling, and energy homeostasis. PP-IPs function to regulate their target proteins through allosteric interactions or protein pyrophosphorylation. This review summarizes the current understanding of how PP-IPs control mammalian cellular signaling networks in physiology and disease.
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Case KC, Salsaa M, Yu W, Greenberg ML. Regulation of Inositol Biosynthesis: Balancing Health and Pathophysiology. Handb Exp Pharmacol 2020; 259:221-260. [PMID: 30591968 DOI: 10.1007/164_2018_181] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Inositol is the precursor for all inositol compounds and is essential for viability of eukaryotic cells. Numerous cellular processes and signaling functions are dependent on inositol compounds, and perturbation of their synthesis leads to a wide range of human diseases. Although considerable research has been directed at understanding the function of inositol compounds, especially phosphoinositides and inositol phosphates, a focus on regulatory and homeostatic mechanisms controlling inositol biosynthesis has been largely neglected. Consequently, little is known about how synthesis of inositol is regulated in human cells. Identifying physiological regulators of inositol synthesis and elucidating the molecular mechanisms that regulate inositol synthesis will contribute fundamental insight into cellular processes that are mediated by inositol compounds and will provide a foundation to understand numerous disease processes that result from perturbation of inositol homeostasis. In addition, elucidating the mechanisms of action of inositol-depleting drugs may suggest new strategies for the design of second-generation pharmaceuticals to treat psychiatric disorders and other illnesses.
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Affiliation(s)
- Kendall C Case
- Department of Biological Sciences, Wayne State University, Detroit, MI, USA
| | - Michael Salsaa
- Department of Biological Sciences, Wayne State University, Detroit, MI, USA
| | - Wenxi Yu
- Department of Biological Sciences, Wayne State University, Detroit, MI, USA
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Miriam L Greenberg
- Department of Biological Sciences, Wayne State University, Detroit, MI, USA.
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23
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Ganguli S, Shah A, Hamid A, Singh A, Palakurti R, Bhandari R. A high energy phosphate jump - From pyrophospho-inositol to pyrophospho-serine. Adv Biol Regul 2020; 75:100662. [PMID: 31668836 DOI: 10.1016/j.jbior.2019.100662] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 09/26/2019] [Accepted: 09/30/2019] [Indexed: 06/10/2023]
Abstract
Inositol pyrophosphates (PP-IPs) are a class of energy rich metabolites present in all eukaryotic cells. The hydroxyl groups on these water soluble derivatives of inositol are substituted with diphosphate and monophosphate moieties. Since the discovery of PP-IPs in the early 1990s, enormous progress has been made in uncovering pleiotropic roles for these small molecules in cellular physiology. PP-IPs exert their effect on proteins in two ways - allosteric regulation by direct binding, or post-translational regulation by serine pyrophosphorylation, a modification unique to PP-IPs. Serine pyrophosphorylation is achieved by Mg2+-dependent, but enzyme independent transfer of a β-phosphate from a PP-IP to a pre-phosphorylated serine residue located in an acidic motif, within an intrinsically disordered protein sequence. This distinctive post-translational modification has been shown to regulate diverse cellular processes, including rRNA synthesis, glycolysis, and vesicle transport. However, our understanding of the molecular details of this phosphotransfer from pyrophospho-inositol to generate pyrophospho-serine, is still nascent. This review discusses our current knowledge of protein pyrophosphorylation, and recent advances in understanding the mechanism of this important yet overlooked post-translational modification.
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Affiliation(s)
- Shubhra Ganguli
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India; Manipal Academy of Higher Education, Manipal, 576104, India
| | - Akruti Shah
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India; Manipal Academy of Higher Education, Manipal, 576104, India
| | - Aisha Hamid
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India
| | - Arpita Singh
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India
| | - Ravichand Palakurti
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India
| | - Rashna Bhandari
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India.
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24
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Wormald MM, Ernst G, Wei H, Barrow JC. Synthesis and characterization of novel isoform-selective IP6K1 inhibitors. Bioorg Med Chem Lett 2019; 29:126628. [PMID: 31445853 DOI: 10.1016/j.bmcl.2019.126628] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/15/2019] [Accepted: 08/17/2019] [Indexed: 11/25/2022]
Abstract
Inositol hexakisphosphate kinases (IP6Ks) have been increasingly studied as therapeutically interesting enzymes. IP6K isoform specific knock-outs have been used to successfully explore inositol pyrophosphate physiology and related pathologies. A pan-IP6K inhibitor, N2-(m-trifluorobenzyl)-N6-(p-nitrobenzyl) purine (TNP), has been used to confirm phenotypes observed in genetic knock-out experiments; however, it suffers by having modest potency and poor solubility making it difficult to handle for in vitro applications in the absence of DMSO. Moreover, TNP's pan-IP6K inhibitory profile does not inform which IP6K isoform is responsible for which phenotypes. In this report we describe a series of purine-based isoform specific IP6K1 inhibitors. The lead compound was identified after multiple rounds of SAR and has been found to selectively inhibit IP6K1 over IP6K2 or IP6K3 using biochemical and biophysical approaches. It also boasts increased solubility and IP6K1 potency over TNP. These new compounds are useful tools for additional assay development and exploration of IP6K1 specific biology.
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Affiliation(s)
- Michael M Wormald
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, MD 21205, USA
| | - Glen Ernst
- Lieber Institute for Brain Development, 855 North Wolfe Street, Baltimore, MD 21205, USA
| | - Huijun Wei
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, MD 21205, USA; Lieber Institute for Brain Development, 855 North Wolfe Street, Baltimore, MD 21205, USA
| | - James C Barrow
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, MD 21205, USA; Lieber Institute for Brain Development, 855 North Wolfe Street, Baltimore, MD 21205, USA.
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25
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Zhuang Z, Li S, Ding R, Yang M, Zheng E, Yang H, Gu T, Xu Z, Cai G, Wu Z, Yang J. Meta-analysis of genome-wide association studies for loin muscle area and loin muscle depth in two Duroc pig populations. PLoS One 2019; 14:e0218263. [PMID: 31188900 PMCID: PMC6561594 DOI: 10.1371/journal.pone.0218263] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 05/29/2019] [Indexed: 01/07/2023] Open
Abstract
Loin muscle area (LMA) and loin muscle depth (LMD) are important traits influencing the production performance of breeding pigs. However, the genetic architecture of these two traits is still poorly understood. To discern the genetic architecture of LMA and LMD, a material consisting of 6043 Duroc pigs belonging to two populations with different genetic backgrounds was collected and applied in genome-wide association studies (GWAS) with a genome-wide distributed panel of 50K single nucleotide polymorphisms (SNPs). To improve the power of detection for common SNPs, we conducted a meta-analysis in these two pig populations and uncovered additional significant SNPs. As a result, we identified 75 significant SNPs for LMA and LMD on SSC6, 7, 12, 16, and 18. Among them, 25 common SNPs were associated with LMA and LMD. One pleiotropic quantitative trait locus (QTL), which was located on SSC7 with a 283 kb interval, was identified to affect LMA and LMD. Marker ALGA0040260 is a key SNP for this QTL, explained 1.77% and 2.48% of the phenotypic variance for LMA and LMD, respectively. Another genetic region on SSC16 (709 kb) was detected and displayed prominent association with LMA and the peak SNP, WU_10.2_16_35829257, contributed 1.83% of the phenotypic variance for LMA. Further bioinformatics analysis determined eight promising candidate genes (GCLC, GPX8, DAXX, FGF21, TAF11, SPDEF, NUDT3, and PACSIN1) with functions in glutathione metabolism, adipose and muscle tissues development and lipid metabolism. This study provides the first GWAS for the LMA and LMD of Duroc breed to analyze the underlying genetic variants through a large sample size. The findings further advance our understanding and help elucidate the genetic architecture of LMA, LMD and growth-related traits in pigs.
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Affiliation(s)
- Zhanwei Zhuang
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
| | - Shaoyun Li
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
| | - Rongrong Ding
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
| | - Ming Yang
- National Engineering Research Center for Breeding Swine Industry, Guangdong Wens Foodstuffs Group Co., Ltd, Guangdong, P.R. China
| | - Enqin Zheng
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
| | - Huaqiang Yang
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
| | - Ting Gu
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
| | - Zheng Xu
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
| | - Gengyuan Cai
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
| | - Zhenfang Wu
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
- National Engineering Research Center for Breeding Swine Industry, Guangdong Wens Foodstuffs Group Co., Ltd, Guangdong, P.R. China
- * E-mail: (JY); (ZW)
| | - Jie Yang
- College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangdong, P.R. China
- * E-mail: (JY); (ZW)
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26
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Wilson MS, Jessen HJ, Saiardi A. The inositol hexakisphosphate kinases IP6K1 and -2 regulate human cellular phosphate homeostasis, including XPR1-mediated phosphate export. J Biol Chem 2019; 294:11597-11608. [PMID: 31186349 PMCID: PMC6663863 DOI: 10.1074/jbc.ra119.007848] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 06/04/2019] [Indexed: 01/08/2023] Open
Abstract
Phosphate's central role in most biochemical reactions in a living organism requires carefully maintained homeostasis. Although phosphate homeostasis in mammals has long been studied at the organismal level, the intracellular mechanisms controlling phosphate metabolism are not well-understood. Inositol pyrophosphates have emerged as important regulatory elements controlling yeast phosphate homeostasis. To verify whether inositol pyrophosphates also regulate mammalian cellular phosphate homeostasis, here we knocked out inositol hexakisphosphate kinase (IP6K) 1 and IP6K2 to generate human HCT116 cells devoid of any inositol pyrophosphates. Using PAGE and HPLC analysis, we observed that the IP6K1/2-knockout cells have nondetectable levels of the IP6-derived IP7 and IP8 and also exhibit reduced synthesis of the IP5-derived PP-IP4. Nucleotide analysis showed that the knockout cells contain increased amounts of ATP, whereas the Malachite green assay found elevated levels of free intracellular phosphate. Furthermore, [32Pi] pulse labeling experiments uncovered alterations in phosphate flux, with both import and export of phosphate being decreased in the knockout cells. Functional analysis of the phosphate exporter xenotropic and polytropic retrovirus receptor 1 (XPR1) revealed that it is regulated by inositol pyrophosphates, which can bind to its SPX domain. We conclude that IP6K1 and -2 together control inositol pyrophosphate metabolism and thereby physiologically regulate phosphate export and other aspects of mammalian cellular phosphate homeostasis.
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Affiliation(s)
- Miranda S Wilson
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Henning J Jessen
- Institute of Organic Chemistry, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Adolfo Saiardi
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
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27
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Kim J, Darè E, Rajasekaran SS, Ryu SH, Berggren PO, Barker CJ. Inositol pyrophosphates and Akt/PKB: Is the pancreatic β-cell the exception to the rule? Cell Signal 2019; 58:131-136. [DOI: 10.1016/j.cellsig.2019.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 01/30/2019] [Accepted: 02/07/2019] [Indexed: 12/14/2022]
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Differential expression and bioinformatics analysis of circRNA in osteosarcoma. Biosci Rep 2019; 39:BSR20181514. [PMID: 31036604 PMCID: PMC6522716 DOI: 10.1042/bsr20181514] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 04/15/2019] [Accepted: 04/24/2019] [Indexed: 01/14/2023] Open
Abstract
AIM This research aims to investigate the expression profile of circRNA in osteosarcoma and to identify the underlying pathogenesis core genes of osteosarcoma.Methods: Illumina HiSeq was used to screen differentially expressed circRNAs between the tumour tissues and paracancerous tissues of three osteosarcoma patients. Bioinformatics analysis was used to analyse their potential functions. Five differentially expressed circRNAs were selected to detect the relative expression level in tumour and paracancerous tissues of ten osteosarcoma patients by real-time PCR. The databases such as DisGeNET and miRWalk were used to collect related genes or miRNAs. RESULTS A total of 259 differentially expressed circRNAs were evaluated in patients with osteosarcoma, of which 132 were up-regulated and 127 were down-regulated. Compared with that in paracancerous tissues, circ_32279 and circ_24831 were significantly down-regulated while circ_2137 and circ_20403 were significantly up-regulated in osteosarcoma tissues. The differential expression of circRNA is closely linked to biological processes and molecular functions. The difference in circRNA was mainly linked to the 'phosphatidylinositol signalling system' signal pathway and the 'inositol phosphate metabolism' signal pathway. CONCLUSION The present study identified a profile of abnormal regulation of circRNA in osteosarcoma. Bioinformatics analysis indicates that the deregulated circRNAs may be related to the occurrence and development of osteosarcoma.
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Hauke S, Dutta AK, Eisenbeis VB, Bezold D, Bittner T, Wittwer C, Thakor D, Pavlovic I, Schultz C, Jessen HJ. Photolysis of cell-permeant caged inositol pyrophosphates controls oscillations of cytosolic calcium in a β-cell line. Chem Sci 2019; 10:2687-2692. [PMID: 30996985 PMCID: PMC6419925 DOI: 10.1039/c8sc03479f] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 01/09/2019] [Indexed: 12/16/2022] Open
Abstract
β-Cells respond directly to the intracellular photochemical release of caged inositol pyrophosphate isomers with modulations of oscillations in cytosolic Ca2+.
Among many cellular functions, inositol pyrophosphates (PP-InsPs) are metabolic messengers involved in the regulation of glucose uptake, insulin sensitivity, and weight gain. However, their mechanisms of action are still poorly understood. So far, the influence of PP-InsPs on cellular metabolism has been studied by overexpression or knockout/inhibition of relevant metabolizing kinases (IP6Ks, PPIP5Ks). These approaches are, inter alia, limited by time-resolution and potential compensation mechanisms. Here, we describe the synthesis of cell-permeant caged PP-InsPs as tools to rapidly modulate intracellular levels of defined isomers of PP-InsPs in a genetically non-perturbed cellular environment. We show that caged prometabolites readily enter live cells where they are enzymatically converted into still inactive, metabolically stable, photocaged PP-InsPs. Upon light-triggered release of 5-PP-InsP5, the major cellular inositol pyrophosphate, oscillations of intracellular Ca2+ levels in MIN6 cells were transiently reduced to spontaneously recover again. In contrast, uncaging of 1-PP-InsP5, a minor cellular isomer, was without effect. These results provide evidence that PP-InsPs play an active role in regulating [Ca2+]i oscillations, a key element in triggering exocytosis and secretion in β-cells.
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Affiliation(s)
- S Hauke
- EMBL, Heidelberg , 69117 Heidelberg , Germany .
| | - A K Dutta
- University of Freiburg , Institute of Organic Chemistry , 79104 Freiburg , Germany .
| | - V B Eisenbeis
- University of Freiburg , Institute of Organic Chemistry , 79104 Freiburg , Germany .
| | - D Bezold
- University of Freiburg , Institute of Organic Chemistry , 79104 Freiburg , Germany .
| | - T Bittner
- University of Freiburg , Institute of Organic Chemistry , 79104 Freiburg , Germany .
| | - C Wittwer
- University of Freiburg , Institute of Organic Chemistry , 79104 Freiburg , Germany .
| | - D Thakor
- University of Freiburg , Institute of Organic Chemistry , 79104 Freiburg , Germany .
| | - I Pavlovic
- University of Freiburg , Institute of Organic Chemistry , 79104 Freiburg , Germany .
| | - C Schultz
- EMBL, Heidelberg , 69117 Heidelberg , Germany . .,OHSU , Dept. Physiology & Pharmacology , Portland , OR , USA .
| | - H J Jessen
- University of Freiburg , Institute of Organic Chemistry , 79104 Freiburg , Germany .
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Do inositol supplements enhance phosphatidylinositol supply and thus support endoplasmic reticulum function? Br J Nutr 2018; 120:301-316. [PMID: 29859544 DOI: 10.1017/s0007114518000946] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This review attempts to explain why consuming extra myoinositol (Ins), an essential component of membrane phospholipids, is often beneficial for patients with conditions characterised by insulin resistance, non-alcoholic fatty liver disease and endoplasmic reticulum (ER) stress. For decades we assumed that most human diets provide an adequate Ins supply, but newer evidence suggests that increasing Ins intake ameliorates several disorders, including polycystic ovary syndrome, gestational diabetes, metabolic syndrome, poor sperm development and retinopathy of prematurity. Proposed explanations often suggest functional enhancement of minor facets of Ins Biology such as insulin signalling through putative inositol-containing 'mediators', but offer no explanation for this selectivity. It is more likely that eating extra Ins corrects a deficiency of an abundant Ins-containing cell constituent, probably phosphatidylinositol (PtdIns). Much of a cell's PtdIns is in ER membranes, and an increase in ER membrane synthesis, enhancing the ER's functional capacity, is often an important part of cell responses to ER stress. This review: (a) reinterprets historical information on Ins deficiency as describing a set of events involving a failure of cells adequately to adapt to ER stress; (b) proposes that in the conditions that respond to dietary Ins there is an overstretching of Ins reserves that limits the stressed ER's ability to make the 'extra' PtdIns needed for ER membrane expansion; and (c) suggests that eating Ins supplements increases the Ins supply to Ins-deficient and ER-stressed cells, allowing them to make more PtdIns and to expand the ER membrane system and sustain ER functions.
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Chakraborty A. The inositol pyrophosphate pathway in health and diseases. Biol Rev Camb Philos Soc 2018; 93:1203-1227. [PMID: 29282838 PMCID: PMC6383672 DOI: 10.1111/brv.12392] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 11/28/2017] [Accepted: 12/05/2017] [Indexed: 12/11/2022]
Abstract
Inositol pyrophosphates (IPPs) are present in organisms ranging from plants, slime moulds and fungi to mammals. Distinct classes of kinases generate different forms of energetic diphosphate-containing IPPs from inositol phosphates (IPs). Conversely, polyphosphate phosphohydrolase enzymes dephosphorylate IPPs to regenerate the respective IPs. IPPs and/or their metabolizing enzymes regulate various cell biological processes by modulating many proteins via diverse mechanisms. In the last decade, extensive research has been conducted in mammalian systems, particularly in knockout mouse models of relevant enzymes. Results obtained from these studies suggest impacts of the IPP pathway on organ development, especially of brain and testis. Conversely, deletion of specific enzymes in the pathway protects mice from various diseases such as diet-induced obesity (DIO), type-2 diabetes (T2D), fatty liver, bacterial infection, thromboembolism, cancer metastasis and aging. Furthermore, pharmacological inhibition of the same class of enzymes in mice validates the therapeutic importance of this pathway in cardio-metabolic diseases. This review critically analyses these findings and summarizes the significance of the IPP pathway in mammalian health and diseases. It also evaluates benefits and risks of targeting this pathway in disease therapies. Finally, future directions of mammalian IPP research are discussed.
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Affiliation(s)
- Anutosh Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO 63104, U.S.A
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32
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Yousaf R, Gu C, Ahmed ZM, Khan SN, Friedman TB, Riazuddin S, Shears SB, Riazuddin S. Mutations in Diphosphoinositol-Pentakisphosphate Kinase PPIP5K2 are associated with hearing loss in human and mouse. PLoS Genet 2018; 14:e1007297. [PMID: 29590114 PMCID: PMC5891075 DOI: 10.1371/journal.pgen.1007297] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 04/09/2018] [Accepted: 03/06/2018] [Indexed: 01/07/2023] Open
Abstract
Autosomal recessive nonsyndromic hearing loss is a genetically heterogeneous disorder. Here, we report a severe-to-profound sensorineural hearing loss locus, DFNB100 on chromosome 5q13.2-q23.2. Exome enrichment followed by massive parallel sequencing revealed a c.2510G>A transition variant in PPIP5K2 that segregated with DFNB100-associated hearing loss in two large apparently unrelated Pakistani families. PPIP5Ks enzymes interconvert 5-IP7 and IP8, two key members of the inositol pyrophosphate (PP-IP) cell-signaling family. Their actions at the interface of cell signaling and bioenergetic homeostasis can impact many biological processes. The c.2510G>A transition variant is predicted to substitute a highly invariant arginine residue with histidine (p.Arg837His) in the phosphatase domain of PPIP5K2. Biochemical studies revealed that the p.Arg837His variant reduces the phosphatase activity of PPIP5K2 and elevates its kinase activity. We found that in mouse inner ear, PPIP5K2 is expressed in the cochlear and vestibular sensory hair cells, supporting cells and spiral ganglion neurons. Mice homozygous for a targeted deletion of the Ppip5k2 phosphatase domain exhibit degeneration of cochlear outer hair cells and elevated hearing thresholds. Our demonstration that PPIP5K2 has a role in hearing in humans indicates that PP-IP signaling is important to hair cell maintenance and function within inner ear. Exome sequencing coupled with homozygosity mapping was used to identify a missense variant [c.2510G>A; p.(Arg837His)] in PPIP5K2 at the DFNB100 locus that is associated with nonsyndromic, prelingual sensorineural deafness in two large consanguineous Pakistani families. PPIP5Ks are pivotal enzymes for regulating inositol pyrophosphate (PP-IP) turnover. Biochemical analyses revealed that, compared to wild type human PPIP5K2, the PPIP5K2R837H variant exhibited lower phosphatase activity and higher kinase activity, indicating that it promotes increased metabolic flux from 5-IP7 to IP8 in vivo. In rodent inner ears, PPIP5K2 immunoreactivity was observed in the cochlear and vestibular hair cells, supporting cells, and spiral ganglion neurons. Mouse mutants homozygous for the targeted deletion of Ppip5k2 phosphatase domain exhibit degeneration of cochlear outer hair cells and progressive hearing loss. Our work provides the first description of any amino acid variant of PPIP5K2 that is both functionally-significant and associates with a human disorder. The ‘futile cycling’ of the kinase/phosphatase activity of PPIP5K2 makes inner ear function particularly susceptible to even minor changes in the phosphatase activity of PPIP5K2. We have shown that a pathogenic variant in PPIP5K2 is associated with hearing loss in humans. Thus, PPIP5K2 is given new clinical significance by our observations.
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Affiliation(s)
- Rizwan Yousaf
- Laboratory of Molecular Genetics, Department of Otorhinolaryngology-Head & Neck Surgery, School of Medicine University of Maryland, Baltimore, MD, United States of America
| | - Chunfang Gu
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, United States of America
| | - Zubair M. Ahmed
- Laboratory of Neurogenetics and Regenerative Medicine, Department of Otorhinolaryngology-Head & Neck Surgery, School of Medicine University of Maryland, Baltimore, MD, United States of America
| | - Shaheen N. Khan
- National Center for Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Thomas B. Friedman
- Section on Human Genetics, Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States of America
| | - Sheikh Riazuddin
- Shaheed Zulfiqar Ali Bhutto Medical University, Pakistan Institute of Medical Sciences, Islamabad, Pakistan
| | - Stephen B. Shears
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, United States of America
| | - Saima Riazuddin
- Laboratory of Molecular Genetics, Department of Otorhinolaryngology-Head & Neck Surgery, School of Medicine University of Maryland, Baltimore, MD, United States of America
- * E-mail:
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Rajasekaran SS, Kim J, Gaboardi GC, Gromada J, Shears SB, Dos Santos KT, Nolasco EL, Ferreira SDS, Illies C, Köhler M, Gu C, Ryu SH, Martins JO, Darè E, Barker CJ, Berggren PO. Inositol hexakisphosphate kinase 1 is a metabolic sensor in pancreatic β-cells. Cell Signal 2018. [PMID: 29522819 PMCID: PMC5899964 DOI: 10.1016/j.cellsig.2018.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Diphosphoinositol pentakisphosphate (IP7) is critical for the exocytotic capacity of the pancreatic β-cell, but its regulation by the primary instigator of β-cell exocytosis, glucose, is unknown. The high Km for ATP of the IP7-generating enzymes, the inositol hexakisphosphate kinases (IP6K1 and 2) suggests that these enzymes might serve as metabolic sensors in insulin secreting β-cells and act as translators of disrupted metabolism in diabetes. We investigated this hypothesis and now show that glucose stimulation, which increases the ATP/ADP ratio, leads to an early rise in IP7 concentration in β-cells. RNAi mediated knock down of the IP6K1 isoform inhibits both glucose-mediated increase in IP7 and first phase insulin secretion, demonstrating that IP6K1 integrates glucose metabolism and insulin exocytosis. In diabetic mouse islets the deranged ATP/ADP levels under both basal and glucose-stimulated conditions are mirrored in both disrupted IP7 generation and insulin release. Thus the unique metabolic sensing properties of IP6K1 guarantees appropriate concentrations of IP7 and thereby both correct basal insulin secretion and intact first phase insulin release. In addition, our data suggest that a specific cell signaling defect, namely, inappropriate IP7 generation may be an essential convergence point integrating multiple metabolic defects into the commonly observed phenotype in diabetes. Glucose increases IP7 levels transiently through IP6K1 in pancreatic β-cells. IP6K1 decodes glucose-driven increases in ATP/ADP ratio into 1st phase insulin release. IP7 production and insulin release mirror perturbed metabolism in diabetic islets. IP6K1 acts as a β-cell metabolic sensor under normal and pathological conditions.
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Affiliation(s)
- Subu Surendran Rajasekaran
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Jaeyoon Kim
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Gian-Carlo Gaboardi
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | | | - Stephen B Shears
- Signal Transduction Laboratory/Inositol Signaling Group, NIEHS, Building 101, Room F239,111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Karen Tiago Dos Santos
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Eduardo Lima Nolasco
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Sabrina de Souza Ferreira
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Christopher Illies
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Martin Köhler
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Chunfang Gu
- Signal Transduction Laboratory/Inositol Signaling Group, NIEHS, Building 101, Room F239,111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Joilson O Martins
- Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Elisabetta Darè
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Christopher J Barker
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden.
| | - Per-Olof Berggren
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea.
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Zhang Q, van Wijk R, Shahbaz M, Roels W, Schooten BV, Vermeer JEM, Zarza X, Guardia A, Scuffi D, García-Mata C, Laha D, Williams P, Willems LAJ, Ligterink W, Hoffmann-Benning S, Gillaspy G, Schaaf G, Haring MA, Laxalt AM, Munnik T. Arabidopsis Phospholipase C3 is Involved in Lateral Root Initiation and ABA Responses in Seed Germination and Stomatal Closure. PLANT & CELL PHYSIOLOGY 2018; 59:469-486. [PMID: 29309666 DOI: 10.1093/pcp/pcx194] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 12/01/2017] [Indexed: 05/10/2023]
Abstract
Phospholipase C (PLC) is well known for its role in animal signaling, where it generates the second messengers, inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG), by hydrolyzing the minor phospholipid, phosphatidylinositol 4,5-bisphosphate (PIP2), upon receptor stimulation. In plants, PLC's role is still unclear, especially because the primary targets of both second messengers are lacking, i.e. the ligand-gated Ca2+ channel and protein kinase C, and because PIP2 levels are extremely low. Nonetheless, the Arabidopsis genome encodes nine PLCs. We used a reversed-genetic approach to explore PLC's function in Arabidopsis, and report here that PLC3 is required for proper root development, seed germination and stomatal opening. Two independent knock-down mutants, plc3-2 and plc3-3, were found to exhibit reduced lateral root densities by 10-20%. Mutant seeds germinated more slowly but were less sensitive to ABA to prevent germination. Guard cells of plc3 were also compromised in ABA-dependent stomatal closure. Promoter-β-glucuronidase (GUS) analyses confirmed PLC3 expression in guard cells and germinating seeds, and revealed that the majority is expressed in vascular tissue, most probably phloem companion cells, in roots, leaves and flowers. In vivo 32Pi labeling revealed that ABA stimulated the formation of PIP2 in germinating seeds and guard cell-enriched leaf peels, which was significantly reduced in plc3 mutants. Overexpression of PLC3 had no effect on root system architecture or seed germination, but increased the plant's tolerance to drought. Our results provide genetic evidence for PLC's involvement in plant development and ABA signaling, and confirm earlier observations that overexpression increases drought tolerance. Potential molecular mechanisms for the above observations are discussed.
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Affiliation(s)
- Qianqian Zhang
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
- Swammerdam Institute for Life Sciences, section Plant Cell Biology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
| | - Ringo van Wijk
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
- Swammerdam Institute for Life Sciences, section Plant Cell Biology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
| | - Muhammad Shahbaz
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
| | - Wendy Roels
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
| | - Bas van Schooten
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
| | - Joop E M Vermeer
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Xavier Zarza
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
- Swammerdam Institute for Life Sciences, section Plant Cell Biology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
| | - Aisha Guardia
- Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| | - Denise Scuffi
- Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| | - Carlos García-Mata
- Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| | - Debabrata Laha
- Center for Plant Molecular Biology, University of Tübingen, Tübingen, Germany
- Institute of Crop Science and Resource Conservation, Department of Plant Nutrition, University of Bonn, Bonn, Germany
| | - Phoebe Williams
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Leo A J Willems
- Laboratory of Plant Physiology, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Wilco Ligterink
- Laboratory of Plant Physiology, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Susanne Hoffmann-Benning
- Departement of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Glenda Gillaspy
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Gabriel Schaaf
- Center for Plant Molecular Biology, University of Tübingen, Tübingen, Germany
- Institute of Crop Science and Resource Conservation, Department of Plant Nutrition, University of Bonn, Bonn, Germany
| | - Michel A Haring
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
| | - Ana M Laxalt
- Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| | - Teun Munnik
- Swammerdam Institute for Life Sciences, section Plant Physiology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
- Swammerdam Institute for Life Sciences, section Plant Cell Biology, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands
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Belgaroui N, Lacombe B, Rouached H, Hanin M. Phytase overexpression in Arabidopsis improves plant growth under osmotic stress and in combination with phosphate deficiency. Sci Rep 2018; 8:1137. [PMID: 29348608 PMCID: PMC5773496 DOI: 10.1038/s41598-018-19493-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 12/07/2017] [Indexed: 12/28/2022] Open
Abstract
Engineering osmotolerant plants is a challenge for modern agriculture. An interaction between osmotic stress response and phosphate homeostasis has been reported in plants, but the identity of molecules involved in this interaction remains unknown. In this study we assessed the role of phytic acid (PA) in response to osmotic stress and/or phosphate deficiency in Arabidopsis thaliana. For this purpose, we used Arabidopsis lines (L7 and L9) expressing a bacterial beta-propeller phytase PHY-US417, and a mutant in inositol polyphosphate kinase 1 gene (ipk1-1), which were characterized by low PA content, 40% (L7 and L9) and 83% (ipk1-1) of the wild-type (WT) plants level. We show that the PHY-overexpressor lines have higher osmotolerance and lower sensitivity to abscisic acid than ipk1-1 and WT. Furthermore, PHY-overexpressors showed an increase by more than 50% in foliar ascorbic acid levels and antioxidant enzyme activities compared to ipk1-1 and WT plants. Finally, PHY-overexpressors are more tolerant to combined mannitol stresses and phosphate deficiency than WT plants. Overall, our results demonstrate that the modulation of PA improves plant growth under osmotic stress, likely via stimulation of enzymatic and non-enzymatic antioxidant systems, and that beside its regulatory role in phosphate homeostasis, PA may be also involved in fine tuning osmotic stress response in plants.
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Affiliation(s)
- Nibras Belgaroui
- Laboratoire de Biotechnologie et Amélioration des Plantes, Centre de Biotechnologie de Sfax, BP "1177", 3018, Sfax, Tunisia
| | - Benoit Lacombe
- BPMP, CNRS, INRA, Montpellier SupAgro, Univ Montpellier, Montpellier, France
| | - Hatem Rouached
- BPMP, CNRS, INRA, Montpellier SupAgro, Univ Montpellier, Montpellier, France.
| | - Moez Hanin
- Laboratoire de Biotechnologie et Amélioration des Plantes, Centre de Biotechnologie de Sfax, BP "1177", 3018, Sfax, Tunisia. .,Unité de Génomique Fonctionnelle et Physiologie des Plantes, Institut Supérieur de Biotechnologie, Université de Sfax, BP "1175", 3038, Sfax, Tunisia.
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Brown NW, Marmelstein AM, Fiedler D. Chemical tools for interrogating inositol pyrophosphate structure and function. Chem Soc Rev 2018; 45:6311-6326. [PMID: 27462803 DOI: 10.1039/c6cs00193a] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The inositol pyrophosphates (PP-InsPs) are a unique group of intracellular messengers that represent some of the most highly phosphorylated molecules in nature. Genetic perturbation of the PP-InsP biosynthetic network indicates a central role for these metabolites in maintaining cellular energy homeostasis and in controlling signal transduction networks. However, despite their discovery over two decades ago, elucidating their physiologically relevant isomers, the biochemical pathways connecting these molecules to their associated phenotypes, and their modes of signal transduction has often been stymied by technical challenges. Many of the advances in understanding these molecules to date have been facilitated by the total synthesis of the various PP-InsP isomers and by the development of new methods that are capable of identifying their downstream signalling partners. Chemical tools have also been developed to distinguish between the proposed PP-InsP signal transduction mechanisms: protein binding, and a covalent modification of proteins termed protein pyrophosphorylation. In this article, we review these recent developments, discuss how they have helped to illuminate PP-InsP structure and function, and highlight opportunities for future discovery.
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Affiliation(s)
- Nathaniel W Brown
- Princeton University, Frick Chemistry Laboratory, Washington Road, Princeton, NJ 08544, USA and Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str 10, 13125 Berlin, Berlin, Germany.
| | - Alan M Marmelstein
- Princeton University, Frick Chemistry Laboratory, Washington Road, Princeton, NJ 08544, USA and Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str 10, 13125 Berlin, Berlin, Germany.
| | - Dorothea Fiedler
- Princeton University, Frick Chemistry Laboratory, Washington Road, Princeton, NJ 08544, USA and Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str 10, 13125 Berlin, Berlin, Germany.
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37
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Park SJ, Lee S, Park SE, Kim S. Inositol pyrophosphates as multifaceted metabolites in the regulation of mammalian signaling networks. Anim Cells Syst (Seoul) 2017. [DOI: 10.1080/19768354.2017.1408684] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Seung Ju Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Seulgi Lee
- 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
| | - Seyun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- KAIST Institute for the BioCentury, KAIST, Daejeon, Republic of Korea
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Rajasekaran SS, Illies C, Shears SB, Wang H, Ayala TS, Martins JO, Daré E, Berggren PO, Barker CJ. Protein kinase- and lipase inhibitors of inositide metabolism deplete IP 7 indirectly in pancreatic β-cells: Off-target effects on cellular bioenergetics and direct effects on IP6K activity. Cell Signal 2017; 42:127-133. [PMID: 29042286 PMCID: PMC5765549 DOI: 10.1016/j.cellsig.2017.10.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 10/11/2017] [Accepted: 10/13/2017] [Indexed: 12/22/2022]
Abstract
Inositol pyrophosphates have emerged as important regulators of many critical cellular processes from vesicle trafficking and cytoskeletal rearrangement to telomere length regulation and apoptosis. We have previously demonstrated that 5-di-phosphoinositol pentakisphosphate, IP7, is at a high level in pancreatic β-cells and is important for insulin exocytosis. To better understand IP7 regulation in β-cells, we used an insulin secreting cell line, HIT-T15, to screen a number of different pharmacological inhibitors of inositide metabolism for their impact on cellular IP7. Although the inhibitors have diverse targets, they all perturbed IP7 levels. This made us suspicious that indirect, off-target effects of the inhibitors could be involved. It is known that IP7 levels are decreased by metabolic poisons. The fact that the inositol hexakisphosphate kinases (IP6Ks) have a high Km for ATP makes IP7 synthesis potentially vulnerable to ATP depletion. Furthermore, many kinase inhibitors are targeted to the ATP binding site of kinases, but given the similarity of such sites, high specificity is difficult to achieve. Here, we show that IP7 concentrations in HIT-T15 cells were reduced by inhibitors of PI3K (wortmannin, LY294002), PI4K (Phenylarsine Oxide, PAO), PLC (U73122) and the insulin receptor (HNMPA). Each of these inhibitors also decreased the ATP/ADP ratio. Thus reagents that compromise energy metabolism reduce IP7 indirectly. Additionally, PAO, U73122 and LY294002 also directly inhibited the activity of purified IP6K. These data are of particular concern for those studying signal transduction in pancreatic β-cells, but also highlight the fact that employment of these inhibitors could have erroneously suggested the involvement of key signal transduction pathways in various cellular processes. Conversely, IP7’s role in cellular signal transduction is likely to have been underestimated. In pancreatic β-cells several inhibitors of signal transduction reduce IP7 levels. There is a positive correlation between IP7 reduction and decrease in ATP/ADP. Inhibitors deplete IP7 levels indirectly by decreasing ATP/ADP levels. Some purportedly specific cell-signaling inhibitors directly target IP6K activity. Caution is required in interpreting data obtained using inhibitors of inositide metabolism.
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Affiliation(s)
- Subu Surendran Rajasekaran
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Christopher Illies
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Stephen B Shears
- Signal Transduction Laboratory/Inositol Signaling Group, NIEHS, Building 101, Room F239, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Huanchen Wang
- Signal Transduction Laboratory/Inositol Signaling Group, NIEHS, Building 101, Room F239, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Thais S Ayala
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Joilson O Martins
- Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Elisabetta Daré
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Per-Olof Berggren
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden.
| | - Christopher J Barker
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden.
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Abstract
Genetic ablation of inositol pyrophosphate synthesis has established the fundamental importance of this class of molecules to the eukaryote cell. These studies, however, must be complemented by cell biology and biochemical approaches to appreciate the signalling involved in the processes regulated by inositol pyrophosphates. A recent study by Chanduri et al. published in the Biochemical Journal, by integrating multiple experimental approaches, demonstrated that inositol pyrophosphates regulate intracellular vesicular movement. In particular, the vesicular transport along the microtubule that is driven by the motor protein complex dynein. Importantly, one subunit of this cellular motor, dynein 1 intermediate chain 2, undergoes serine pyrophosphorylation, a post-translational modification driven by inositol pyrophosphates. The pyrophosphorylation status of this dynein intermediate chain regulates its interaction with dynactin, which recruits the motor to vesicles. This mechanistically might explain how inositol pyrophosphates control intracellular membrane trafficking. By dissecting the serine pyrophosphorylation process, this work increases our awareness of this modification, underappreciated by the scientific literature but probably not by the eukaryotic cell.
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40
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Has Inositol Played Any Role in the Origin of Life? Life (Basel) 2017; 7:life7020024. [PMID: 28587245 PMCID: PMC5492146 DOI: 10.3390/life7020024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 05/26/2017] [Accepted: 06/02/2017] [Indexed: 12/11/2022] Open
Abstract
Phosphorus, as phosphate, plays a paramount role in biology. Since phosphate transfer reactions are an integral part of contemporary life, phosphate may have been incorporated into the initial molecules at the very beginning. To facilitate the studies into early phosphate utilization, we should look retrospectively to phosphate-rich molecules present in today’s cells. Overlooked by origin of life studies until now, inositol and the inositol phosphates, of which some species possess more phosphate groups that carbon atoms, represent ideal molecules to consider in this context. The current sophisticated association of inositol with phosphate, and the roles that some inositol phosphates play in regulating cellular phosphate homeostasis, intriguingly suggest that inositol might have played some role in the prebiotic process of phosphate exploitation. Inositol can be synthesized abiotically and, unlike glucose or ribose, is chemically stable. This stability makes inositol the ideal candidate for the earliest organophosphate molecules, as primitive inositol phosphates. I also present arguments suggesting roles for some inositol phosphates in early chemical evolution events. Finally, the possible prebiotic synthesis of inositol pyrophosphates could have generated high-energy molecules to be utilized in primitive trans-phosphorylating processes.
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Srouji JR, Xu A, Park A, Kirsch JF, Brenner SE. The evolution of function within the Nudix homology clan. Proteins 2017; 85:775-811. [PMID: 27936487 PMCID: PMC5389931 DOI: 10.1002/prot.25223] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 10/15/2016] [Accepted: 11/28/2016] [Indexed: 01/01/2023]
Abstract
The Nudix homology clan encompasses over 80,000 protein domains from all three domains of life, defined by homology to each other. Proteins with a domain from this clan fall into four general functional classes: pyrophosphohydrolases, isopentenyl diphosphate isomerases (IDIs), adenine/guanine mismatch-specific adenine glycosylases (A/G-specific adenine glycosylases), and nonenzymatic activities such as protein/protein interaction and transcriptional regulation. The largest group, pyrophosphohydrolases, encompasses more than 100 distinct hydrolase specificities. To understand the evolution of this vast number of activities, we assembled and analyzed experimental and structural data for 205 Nudix proteins collected from the literature. We corrected erroneous functions or provided more appropriate descriptions for 53 annotations described in the Gene Ontology Annotation database in this family, and propose 275 new experimentally-based annotations. We manually constructed a structure-guided sequence alignment of 78 Nudix proteins. Using the structural alignment as a seed, we then made an alignment of 347 "select" Nudix homology domains, curated from structurally determined, functionally characterized, or phylogenetically important Nudix domains. Based on our review of Nudix pyrophosphohydrolase structures and specificities, we further analyzed a loop region downstream of the Nudix hydrolase motif previously shown to contact the substrate molecule and possess known functional motifs. This loop region provides a potential structural basis for the functional radiation and evolution of substrate specificity within the hydrolase family. Finally, phylogenetic analyses of the 347 select protein domains and of the complete Nudix homology clan revealed general monophyly with regard to function and a few instances of probable homoplasy. Proteins 2017; 85:775-811. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- John R. Srouji
- Plant and Microbial Biology DepartmentUniversity of CaliforniaBerkeleyCalifornia94720
- Molecular and Cell Biology DepartmentUniversity of CaliforniaBerkeleyCalifornia94720
- Present address: Molecular and Cellular Biology DepartmentHarvard UniversityCambridgeMassachusetts02138
| | - Anting Xu
- Graduate Study in Comparative Biochemistry, University of CaliforniaBerkeleyCalifornia94720
| | - Annsea Park
- Molecular and Cell Biology DepartmentUniversity of CaliforniaBerkeleyCalifornia94720
| | - Jack F. Kirsch
- Molecular and Cell Biology DepartmentUniversity of CaliforniaBerkeleyCalifornia94720
- Graduate Study in Comparative Biochemistry, University of CaliforniaBerkeleyCalifornia94720
| | - Steven E. Brenner
- Plant and Microbial Biology DepartmentUniversity of CaliforniaBerkeleyCalifornia94720
- Molecular and Cell Biology DepartmentUniversity of CaliforniaBerkeleyCalifornia94720
- Graduate Study in Comparative Biochemistry, University of CaliforniaBerkeleyCalifornia94720
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42
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Azevedo C, Saiardi A. Eukaryotic Phosphate Homeostasis: The Inositol Pyrophosphate Perspective. Trends Biochem Sci 2017; 42:219-231. [DOI: 10.1016/j.tibs.2016.10.008] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 10/21/2016] [Accepted: 10/25/2016] [Indexed: 12/24/2022]
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Shah A, Ganguli S, Sen J, Bhandari R. Inositol Pyrophosphates: Energetic, Omnipresent and Versatile Signalling Molecules. J Indian Inst Sci 2017; 97:23-40. [PMID: 32214696 PMCID: PMC7081659 DOI: 10.1007/s41745-016-0011-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 11/16/2016] [Indexed: 12/21/2022]
Abstract
Inositol pyrophosphates (PP-IPs) are a class of energy-rich signalling molecules found in all eukaryotic cells. These are derivatives of inositol that contain one or more diphosphate (or pyrophosphate) groups in addition to monophosphates. The more abundant and best studied PP-IPs are diphosphoinositol pentakisphosphate (IP7) and bis-diphosphoinositol tetrakisphosphate (IP8). These molecules can influence protein function by two mechanisms: binding and pyrophosphorylation. The former involves the specific interaction of a particular inositol pyrophosphate with a binding site on a protein, while the latter is a unique attribute of inositol pyrophosphates, wherein the β-phosphate moiety is transferred from a PP-IP to a pre-phosphorylated serine residue in a protein to generate pyrophosphoserine. Both these events can result in changes in the target protein’s activity, localisation or its interaction with other partners. As a consequence of their ubiquitous presence in all eukaryotic organisms and all cell types examined till date, and their ability to modify protein function, PP-IPs have been found to participate in a wide range of metabolic, developmental, and signalling pathways. This review highlights
many of the known functions of PP-IPs in the context of their temporal and spatial distribution in eukaryotic cells.
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Affiliation(s)
- Akruti Shah
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana India
- Graduate Studies, Manipal University, Manipal, Karnataka India
| | - Shubhra Ganguli
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana India
- Graduate Studies, Manipal University, Manipal, Karnataka India
| | - Jayraj Sen
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana India
- Graduate Studies, Manipal University, Manipal, Karnataka India
| | - Rashna Bhandari
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana India
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Gu C, Nguyen HN, Hofer A, Jessen HJ, Dai X, Wang H, Shears SB. The Significance of the Bifunctional Kinase/Phosphatase Activities of Diphosphoinositol Pentakisphosphate Kinases (PPIP5Ks) for Coupling Inositol Pyrophosphate Cell Signaling to Cellular Phosphate Homeostasis. J Biol Chem 2017; 292:4544-4555. [PMID: 28126903 PMCID: PMC5377771 DOI: 10.1074/jbc.m116.765743] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 01/25/2017] [Indexed: 12/31/2022] Open
Abstract
Proteins responsible for Pi homeostasis are critical for all life. In Saccharomyces cerevisiae, extracellular [Pi] is "sensed" by the inositol-hexakisphosphate kinase (IP6K) that synthesizes the intracellular inositol pyrophosphate 5-diphosphoinositol 1,2,3,4,6-pentakisphosphate (5-InsP7) as follows: during a period of Pi starvation, there is a decline in cellular [ATP]; the unusually low affinity of IP6Ks for ATP compels 5-InsP7 levels to fall in parallel (Azevedo, C., and Saiardi, A. (2017) Trends. Biochem. Sci. 42, 219-231. Hitherto, such Pi sensing has not been documented in metazoans. Here, using a human intestinal epithelial cell line (HCT116), we show that levels of both 5-InsP7 and ATP decrease upon [Pi] starvation and subsequently recover during Pi replenishment. However, a separate inositol pyrophosphate, 1,5-bisdiphosphoinositol 2,3,4,6-tetrakisphosphate (InsP8), reacts more dramatically (i.e. with a wider dynamic range and greater sensitivity). To understand this novel InsP8 response, we characterized kinetic properties of the bifunctional 5-InsP7 kinase/InsP8 phosphatase activities of full-length diphosphoinositol pentakisphosphate kinases (PPIP5Ks). These data fulfil previously published criteria for any bifunctional kinase/phosphatase to exhibit concentration robustness, permitting levels of the kinase product (InsP8 in this case) to fluctuate independently of varying precursor (i.e. 5-InsP7) pool size. Moreover, we report that InsP8 phosphatase activities of PPIP5Ks are strongly inhibited by Pi (40-90% within the 0-1 mm range). For PPIP5K2, Pi sensing by InsP8 is amplified by a 2-fold activation of 5-InsP7 kinase activity by Pi within the 0-5 mm range. Overall, our data reveal mechanisms that can contribute to specificity in inositol pyrophosphate signaling, regulating InsP8 turnover independently of 5-InsP7, in response to fluctuations in extracellular supply of a key nutrient.
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Affiliation(s)
- Chunfang Gu
- From the Laboratory of Signal Transduction, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina, 27709
| | - Hoai-Nghia Nguyen
- From the Laboratory of Signal Transduction, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina, 27709
| | - Alexandre Hofer
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Henning J Jessen
- Institute of Organic Chemistry, Albert Ludwigs University, Albertstrasse 21, 79104 Freiburg, Germany, and
| | - Xuming Dai
- Division of Cardiology, McAllister Heart Institute, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Huanchen Wang
- From the Laboratory of Signal Transduction, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina, 27709
| | - Stephen B Shears
- From the Laboratory of Signal Transduction, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina, 27709,
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Wilson MSC, Saiardi A. Importance of Radioactive Labelling to Elucidate Inositol Polyphosphate Signalling. Top Curr Chem (Cham) 2017; 375:14. [PMID: 28101851 PMCID: PMC5396384 DOI: 10.1007/s41061-016-0099-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 12/21/2016] [Indexed: 01/09/2023]
Abstract
Inositol polyphosphates, in their water-soluble or lipid-bound forms, represent a large and multifaceted family of signalling molecules. Some inositol polyphosphates are well recognised as defining important signal transduction pathways, as in the case of the calcium release factor Ins(1,4,5)P3, generated by receptor activation-induced hydrolysis of the lipid PtdIns(4,5)P2 by phospholipase C. The birth of inositol polyphosphate research would not have occurred without the use of radioactive phosphate tracers that enabled the discovery of the “PI response”. Radioactive labels, mainly of phosphorus but also carbon and hydrogen (tritium), have been instrumental in the development of this research field and the establishment of the inositol polyphosphates as one of the most important networks of regulatory molecules present in eukaryotic cells. Advancements in microscopy and mass spectrometry and the development of colorimetric assays have facilitated inositol polyphosphate research, but have not eliminated the need for radioactive experimental approaches. In fact, such experiments have become easier with the cloning of the inositol polyphosphate kinases, enabling the systematic labelling of specific positions of the inositol ring with radioactive phosphate. This approach has been valuable for elucidating their metabolic pathways and identifying specific and novel functions for inositol polyphosphates. For example, the synthesis of radiolabelled inositol pyrophosphates has allowed the discovery of a new protein post-translational modification. Therefore, radioactive tracers have played and will continue to play an important role in dissecting the many complex aspects of inositol polyphosphate physiology. In this review we aim to highlight the historical importance of radioactivity in inositol polyphosphate research, as well as its modern usage.
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Affiliation(s)
- Miranda S C Wilson
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Adolfo Saiardi
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK.
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Negrão F, Abánades DR, Jaeeger CF, Rocha DFO, Belaz KRA, Giorgio S, Eberlin MN, Angolini CFF. Lipidomic alterations of in vitro macrophage infection by L. infantum and L. amazonensis. ACTA ACUST UNITED AC 2017; 13:2401-2406. [DOI: 10.1039/c7mb00381a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Lipidomics ofLeishmaniahas been demonstrated and related to its adaptation mechanisms during host-cells infection and its different clinical manifestations.
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Affiliation(s)
- Fernanda Negrão
- ThoMSon Mass Spectrometry Laboratory
- Institute of Chemistry
- University of Campinas
- UNICAMP 13083-970 Campinas – SP
- Brazil
| | - Daniel R. Abánades
- Laboratory of Leishmaniasis
- Department of Animal Biology
- Institute of Biology
- University of Campinas
- UNICAMP 13083-970 Campinas – SP
| | - Caroline F. Jaeeger
- ThoMSon Mass Spectrometry Laboratory
- Institute of Chemistry
- University of Campinas
- UNICAMP 13083-970 Campinas – SP
- Brazil
| | - Daniele F. O. Rocha
- ThoMSon Mass Spectrometry Laboratory
- Institute of Chemistry
- University of Campinas
- UNICAMP 13083-970 Campinas – SP
- Brazil
| | - Katia R. A. Belaz
- ThoMSon Mass Spectrometry Laboratory
- Institute of Chemistry
- University of Campinas
- UNICAMP 13083-970 Campinas – SP
- Brazil
| | - Selma Giorgio
- Laboratory of Leishmaniasis
- Department of Animal Biology
- Institute of Biology
- University of Campinas
- UNICAMP 13083-970 Campinas – SP
| | - Marcos N. Eberlin
- ThoMSon Mass Spectrometry Laboratory
- Institute of Chemistry
- University of Campinas
- UNICAMP 13083-970 Campinas – SP
- Brazil
| | - Célio F. F. Angolini
- ThoMSon Mass Spectrometry Laboratory
- Institute of Chemistry
- University of Campinas
- UNICAMP 13083-970 Campinas – SP
- Brazil
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Gu C, Wilson MSC, Jessen HJ, Saiardi A, Shears SB. Inositol Pyrophosphate Profiling of Two HCT116 Cell Lines Uncovers Variation in InsP8 Levels. PLoS One 2016; 11:e0165286. [PMID: 27788189 PMCID: PMC5082907 DOI: 10.1371/journal.pone.0165286] [Citation(s) in RCA: 27] [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: 05/03/2016] [Accepted: 09/09/2016] [Indexed: 11/18/2022] Open
Abstract
The HCT116 cell line, which has a pseudo-diploid karotype, is a popular model in the fields of cancer cell biology, intestinal immunity, and inflammation. In the current study, we describe two batches of diverged HCT116 cells, which we designate as HCT116NIH and HCT116UCL. Using both gel electrophoresis and HPLC, we show that HCT116UCL cells contain 6-fold higher levels of InsP8 than HCT116NIH cells. This observation is significant because InsP8 is one of a group of molecules collectively known as ‘inositol pyrophosphates’ (PP-InsPs)—highly ‘energetic’ and conserved regulators of cellular and organismal metabolism. Variability in the cellular levels of InsP8 within divergent HCT116 cell lines could have impacted the phenotypic data obtained in previous studies. This difference in InsP8 levels is more remarkable for being specific; levels of other inositol phosphates, and notably InsP6 and 5-InsP7, are very similar in both HCT116NIH and HCT116UCL lines. We also developed a new HPLC procedure to record 1-InsP7 levels directly (for the first time in any mammalian cell line); 1-InsP7 comprised <2% of total InsP7 in HCT116NIH and HCT116UCL lines. The elevated levels of InsP8 in the HCT116UCL lines were not due to an increase in expression of the PP-InsP kinases (IP6Ks and PPIP5Ks), nor to a decrease in the capacity to dephosphorylate InsP8. We discuss how the divergent PP-InsP profiles of the newly-designated HCT116NIH and HCT116UCL lines should be considered an important research opportunity: future studies using these two lines may uncover new features that regulate InsP8 turnover, and may also yield new directions for studying InsP8 function.
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Affiliation(s)
- Chunfang Gu
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, 101 T.W. Alexander Drive, Research Triangle Park, North Carolina, 27709, United States of America
| | - Miranda S. C. Wilson
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Henning J. Jessen
- Institute of Organic Chemistry, Albert-Ludwigs-University, Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Adolfo Saiardi
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- * E-mail: (AS); (SS)
| | - Stephen B. Shears
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, 101 T.W. Alexander Drive, Research Triangle Park, North Carolina, 27709, United States of America
- * E-mail: (AS); (SS)
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Baughman BM, Wang H, An Y, Kireev D, Stashko MA, Jessen HJ, Pearce KH, Frye SV, Shears SB. A High-Throughput Screening-Compatible Strategy for the Identification of Inositol Pyrophosphate Kinase Inhibitors. PLoS One 2016; 11:e0164378. [PMID: 27736936 PMCID: PMC5063353 DOI: 10.1371/journal.pone.0164378] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/24/2016] [Indexed: 11/22/2022] Open
Abstract
Pharmacological tools-'chemical probes'-that intervene in cell signaling cascades are important for complementing genetically-based experimental approaches. Probe development frequently begins with a high-throughput screen (HTS) of a chemical library. Herein, we describe the design, validation, and implementation of the first HTS-compatible strategy against any inositol phosphate kinase. Our target enzyme, PPIP5K, synthesizes 'high-energy' inositol pyrophosphates (PP-InsPs), which regulate cell function at the interface between cellular energy metabolism and signal transduction. We optimized a time-resolved, fluorescence resonance energy transfer ADP-assay to record PPIP5K-catalyzed, ATP-driven phosphorylation of 5-InsP7 to 1,5-InsP8 in 384-well format (Z' = 0.82 ± 0.06). We screened a library of 4745 compounds, all anticipated to be membrane-permeant, which are known-or conjectured based on their structures-to target the nucleotide binding site of protein kinases. At a screening concentration of 13 μM, fifteen compounds inhibited PPIP5K >50%. The potency of nine of these hits was confirmed by dose-response analyses. Three of these molecules were selected from different structural clusters for analysis of binding to PPIP5K, using isothermal calorimetry. Acceptable thermograms were obtained for two compounds, UNC10112646 (Kd = 7.30 ± 0.03 μM) and UNC10225498 (Kd = 1.37 ± 0.03 μM). These Kd values lie within the 1-10 μM range generally recognized as suitable for further probe development. In silico docking data rationalizes the difference in affinities. HPLC analysis confirmed that UNC10225498 and UNC10112646 directly inhibit PPIP5K-catalyzed phosphorylation of 5-InsP7 to 1,5-InsP8; kinetic experiments showed inhibition to be competitive with ATP. No other biological activity has previously been ascribed to either UNC10225498 or UNC10112646; moreover, at 10 μM, neither compound inhibits IP6K2, a structurally-unrelated PP-InsP kinase. Our screening strategy may be generally applicable to inhibitor discovery campaigns for other inositol phosphate kinases.
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Affiliation(s)
- Brandi M. Baughman
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, United States of America
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Huanchen Wang
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, United States of America
| | - Yi An
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Dmitri Kireev
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Michael A. Stashko
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Henning J. Jessen
- Institute of Organic Chemistry, Albert-Ludwigs-University of Freiburg, Freiburg 79104, Germany
| | - Kenneth H. Pearce
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Stephen V. Frye
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Stephen B. Shears
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, United States of America
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Zhu Q, Ghoshal S, Rodrigues A, Gao S, Asterian A, Kamenecka TM, Barrow JC, Chakraborty A. Adipocyte-specific deletion of Ip6k1 reduces diet-induced obesity by enhancing AMPK-mediated thermogenesis. J Clin Invest 2016; 126:4273-4288. [PMID: 27701146 DOI: 10.1172/jci85510] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 08/29/2016] [Indexed: 12/15/2022] Open
Abstract
Enhancing energy expenditure (EE) is an attractive strategy to combat obesity and diabetes. Global deletion of Ip6k1 protects mice from diet-induced obesity (DIO) and insulin resistance, but the tissue-specific mechanism by which IP6K1 regulates body weight is unknown. Here, we have demonstrated that IP6K1 regulates fat accumulation by modulating AMPK-mediated adipocyte energy metabolism. Cold exposure led to downregulation of Ip6k1 in murine inguinal and retroperitoneal white adipose tissue (IWAT and RWAT) depots. Adipocyte-specific deletion of Ip6k1 (AdKO) enhanced thermogenic EE, which protected mice from high-fat diet-induced weight gain at ambient temperature (23°C), but not at thermoneutral temperature (30°C). AdKO-induced increases in thermogenesis also protected mice from cold-induced decreases in body temperature. UCP1, PGC1α, and other markers of browning and thermogenesis were elevated in IWAT and RWAT of AdKO mice. Cold-induced activation of sympathetic signaling was unaltered, whereas AMPK was enhanced, in AdKO IWAT. Moreover, beige adipocytes from AdKO IWAT displayed enhanced browning, which was diminished by AMPK depletion. Furthermore, we determined that IP6 and IP6K1 differentially regulate upstream kinase-mediated AMPK stimulatory phosphorylation in vitro. Finally, treating mildly obese mice with the IP6K inhibitor TNP enhanced thermogenesis and inhibited progression of DIO. Thus, IP6K1 regulates energy metabolism via a mechanism that could potentially be targeted in obesity.
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Couso I, Evans BS, Li J, Liu Y, Ma F, Diamond S, Allen DK, Umen JG. Synergism between Inositol Polyphosphates and TOR Kinase Signaling in Nutrient Sensing, Growth Control, and Lipid Metabolism in Chlamydomonas. THE PLANT CELL 2016; 28:2026-2042. [PMID: 27600537 PMCID: PMC5059802 DOI: 10.1105/tpc.16.00351] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 08/19/2016] [Accepted: 09/02/2016] [Indexed: 05/17/2023]
Abstract
The networks that govern carbon metabolism and control intracellular carbon partitioning in photosynthetic cells are poorly understood. Target of Rapamycin (TOR) kinase is a conserved growth regulator that integrates nutrient signals and modulates cell growth in eukaryotes, though the TOR signaling pathway in plants and algae has yet to be completely elucidated. We screened the unicellular green alga Chlamydomonas reinhardtii using insertional mutagenesis to find mutants that conferred hypersensitivity to the TOR inhibitor rapamycin. We characterized one mutant, vip1-1, that is predicted to encode a conserved inositol hexakisphosphate kinase from the VIP family that pyrophosphorylates phytic acid (InsP6) to produce the low abundance signaling molecules InsP7 and InsP8 Unexpectedly, the rapamycin hypersensitive growth arrest of vip1-1 cells was dependent on the presence of external acetate, which normally has a growth-stimulatory effect on Chlamydomonas. vip1-1 mutants also constitutively overaccumulated triacylglycerols (TAGs) in a manner that was synergistic with other TAG inducing stimuli such as starvation. vip1-1 cells had reduced InsP7 and InsP8, both of which are dynamically modulated in wild-type cells by TOR kinase activity and the presence of acetate. Our data uncover an interaction between the TOR kinase and inositol polyphosphate signaling systems that we propose governs carbon metabolism and intracellular pathways that lead to storage lipid accumulation.
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Affiliation(s)
| | - Bradley S Evans
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Jia Li
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Yu Liu
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Fangfang Ma
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Spencer Diamond
- Earth and Planetary Science, University of California, Berkeley, California 94720
| | - Doug K Allen
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
- Agricultural Research Service, U.S. Department of Agriculture, St. Louis, Missouri 63132
| | - James G Umen
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
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