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Klöckner C, Murray JPF, Tavasoli M, Sticht H, Stoltenburg-Didinger G, Scholle LM, Bakhtiari S, Kruer MC, Darvish H, Firouzabadi SG, Pagnozzi A, Shukla A, Girisha KM, Narayanan DL, Kaur P, Maroofian R, Zaki MS, Noureldeen MM, Merkenschlager A, Gburek-Augustat J, Cali E, Banu S, Nahar K, Efthymiou S, Houlden H, Jamra RA, Williams J, McMaster CR, Platzer K. Bi-allelic variants in CHKA cause a neurodevelopmental disorder with epilepsy and microcephaly. Brain 2022; 145:1916-1923. [PMID: 35202461 DOI: 10.1093/brain/awac074] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 12/15/2021] [Accepted: 02/06/2022] [Indexed: 11/14/2022] Open
Abstract
The Kennedy pathways catalyze the de novo synthesis of phosphatidylcholine and phosphatidylethanolamine, the most abundant components of eukaryotic cell membranes. In recent years, these pathways have moved into clinical focus since four out of ten genes involved have been associated with a range of autosomal recessive rare diseases such as a neurodevelopmental disorder with muscular dystrophy (CHKB), bone abnormalities and cone-rod dystrophy (PCYT1A), and spastic paraplegia (PCYT2, SELENOI). We identified six individuals from five families with bi-allelic variants in CHKA presenting with severe global developmental delay, epilepsy, movement disorders, and microcephaly. Using structural molecular modeling and functional testing of the variants in a in a cell-based S. cerevisiae model, we determined that these variants reduce the enzymatic activity of CHKA and confer a significant impairment of the first enzymatic step of the Kennedy pathway. In summary, we present CHKA as a novel autosomal recessive gene for a neurodevelopmental disorder with epilepsy and microcephaly.
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Affiliation(s)
- Chiara Klöckner
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | | | - Mahtab Tavasoli
- Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia B3N 0A1, Canada
| | - Heinrich Sticht
- Institute of Biochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | | | | | - Somayeh Bakhtiari
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, Arizona, USA.,Departments of Child Health, Neurology, Cellular & Molecular Medicine and Program in Genetics, University of Arizona College of Medicine, Phoenix, Arizona, USA
| | - Michael C Kruer
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, Arizona, USA.,Departments of Child Health, Neurology, Cellular & Molecular Medicine and Program in Genetics, University of Arizona College of Medicine, Phoenix, Arizona, USA
| | - Hossein Darvish
- Neuroscience Research Center, Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran
| | | | - Alex Pagnozzi
- CSIRO Health and Biosecurity, The Australian e-Health Research Centre, Brisbane, QLD 4029, Australia
| | - Anju Shukla
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Katta Mohan Girisha
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Dhanya Lakshmi Narayanan
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Parneet Kaur
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Reza Maroofian
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Mahmoud M Noureldeen
- Department of Pediatrics, Faculty of Medicine, Beni-Suef University, Beni-Suef, Egypt
| | - Andreas Merkenschlager
- Division of Neuropaediatrics, Hospital for Children and Adolescents, University Hospital Leipzig, Leipzig, Germany
| | - Janina Gburek-Augustat
- Division of Neuropaediatrics, Hospital for Children and Adolescents, University Hospital Leipzig, Leipzig, Germany
| | - Elisa Cali
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Selina Banu
- Department of Pediatric Neurology, Dr. M.R. Khan Shishu (Children) Hospital and ICH, Mirpur, Dhaka, Bangladesh
| | - Kamrun Nahar
- Department of Pediatric Neurology, Dr. M.R. Khan Shishu (Children) Hospital and ICH, Mirpur, Dhaka, Bangladesh
| | - Stephanie Efthymiou
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Henry Houlden
- Department of Neuromuscular Disorders, Queen Square Institute of Neurology, University College London, London, UK
| | - Rami Abou Jamra
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Jason Williams
- Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia B3N 0A1, Canada
| | | | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
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Liu R, Lee JH, Li J, Yu R, Tan L, Xia Y, Zheng Y, Bian XL, Lorenzi PL, Chen Q, Lu Z. Choline kinase alpha 2 acts as a protein kinase to promote lipolysis of lipid droplets. Mol Cell 2021; 81:2722-2735.e9. [PMID: 34077757 DOI: 10.1016/j.molcel.2021.05.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/02/2021] [Accepted: 05/07/2021] [Indexed: 02/08/2023]
Abstract
Lipid droplets are important for cancer cell growth and survival. However, the mechanism underlying the initiation of lipid droplet lipolysis is not well understood. We demonstrate here that glucose deprivation induces the binding of choline kinase (CHK) α2 to lipid droplets, which is sequentially mediated by AMPK-dependent CHKα2 S279 phosphorylation and KAT5-dependent CHKα2 K247 acetylation. Importantly, CHKα2 with altered catalytic domain conformation functions as a protein kinase and phosphorylates PLIN2 at Y232 and PLIN3 at Y251. The phosphorylated PLIN2/3 dissociate from lipid droplets and are degraded by Hsc70-mediated autophagy, thereby promoting lipid droplet lipolysis, fatty acid oxidation, and brain tumor growth. In addition, levels of CHKα2 S279 phosphorylation, CHKα2 K247 acetylation, and PLIN2/3 phosphorylation are positively correlated with one another in human glioblastoma specimens and are associated with poor prognosis in glioblastoma patients. These findings underscore the role of CHKα2 as a protein kinase in lipolysis and glioblastoma development.
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Affiliation(s)
- Rui Liu
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, 310029, China; State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Chinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and Management, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, 610041, China.
| | - Jong-Ho Lee
- Department of Health Sciences, The Graduate School of Dong-A University, Busan, 49315, Republic of Korea; Department of Biological Sciences, Dong-A University, Busan 49315, Republic of Korea
| | - Jingyi Li
- The Second Affiliated Hospital of Chengdu Medical College, China National Nuclear Corporation 416 Hospital, Chengdu, Sichuan, 610051, China
| | - Rilei Yu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong 266003, China
| | - Lin Tan
- The Proteomics and Metabolomics Core Facility, Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Yan Xia
- Department of Neuro-Oncology and Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Yanhua Zheng
- Department of Neuro-Oncology and Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Xue-Li Bian
- The Affiliated Hospital of Qingdao University, Qingdao Cancer Institute, Qingdao, Shandong 266071, China
| | - Philip L Lorenzi
- The Proteomics and Metabolomics Core Facility, Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Qianming Chen
- Stomatology Hospital, School of Stomatology, Cancer Center, Zhejiang University School of Medicine, and Key Laboratory of Oral Biomedical Research of Zhejiang Province, Clinical Research Center of Oral Diseases of Zhejiang Province, Hangzhou, 310006, Zhejiang, China.
| | - Zhimin Lu
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, 310029, China; Zhejiang University Cancer Center, Hangzhou, 310029, China.
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3
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Daneshjoo O, hosseini A, Garshasbi M, Pizzuti A. Evidence of involvement of a novel VUS variant in the CHKB gene to congenital muscular dystrophy affection. Meta Gene 2020. [DOI: 10.1016/j.mgene.2020.100698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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4
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Chen X, Qiu H, Wang C, Yuan Y, Tickner J, Xu J, Zou J. Molecular structure and differential function of choline kinases CHKα and CHKβ in musculoskeletal system and cancer. Cytokine Growth Factor Rev 2016; 33:65-72. [PMID: 27769579 DOI: 10.1016/j.cytogfr.2016.10.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 10/04/2016] [Accepted: 10/06/2016] [Indexed: 12/20/2022]
Abstract
Choline, a hydrophilic cation, has versatile physiological roles throughout the body, including cholinergic neurotransmission, memory consolidation and membrane biosynthesis and metabolism. Choline kinases possess enzyme activity that catalyses the conversion of choline to phosphocholine, which is further converted to cytidine diphosphate-coline (CDP-choline) in the biosynthesis of phosphatidylcholine (PC). PC is a major constituent of the phospholipid bilayer which constitutes the eukaryotic cell membrane, and regulates cell signal transduction. Choline Kinase consists of three isoforms, CHKα1, CHKα2 and CHKβ, encoded by two separate genes (CHKA(Human)/Chka(Mouse) and CHKB(Human)/Chkb(Mouse)). Both isoforms have similar structures and enzyme activity, but display some distinct molecular structural domains and differential tissue expression patterns. Whilst Choline Kinase was discovered in early 1950, its pivotal role in the development of muscular dystrophy, bone deformities, and cancer has only recently been identified. CHKα has been proposed as a cancer biomarker and its inhibition as an anti-cancer therapy. In contrast, restoration of CHKβ deficiency through CDP-choline supplements like citicoline may be beneficial for the treatment of muscular dystrophy, bone metabolic diseases, and cognitive conditions. The molecular structure and expression pattern of Choline Kinase, the differential roles of Choline Kinase isoforms and their potential as novel therapeutic targets for muscular dystrophy, bone deformities, cognitive conditions and cancer are discussed.
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Affiliation(s)
- Xi Chen
- School of Kinesiology, Shanghai University of Sport, Shanghai 200438, PR China; School of Sports Science, Wenzhou Medical University, Wenzhou, 325035, PR China; School of Pathology and Laboratory Medicine, The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Heng Qiu
- School of Pathology and Laboratory Medicine, The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Chao Wang
- School of Pathology and Laboratory Medicine, The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Yu Yuan
- School of Kinesiology, Shanghai University of Sport, Shanghai 200438, PR China; School of Pathology and Laboratory Medicine, The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Jennifer Tickner
- School of Pathology and Laboratory Medicine, The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Jiake Xu
- School of Kinesiology, Shanghai University of Sport, Shanghai 200438, PR China; School of Pathology and Laboratory Medicine, The University of Western Australia, Perth, Western Australia, 6009, Australia.
| | - Jun Zou
- School of Kinesiology, Shanghai University of Sport, Shanghai 200438, PR China.
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5
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Zech SG, Kohlmann A, Zhou T, Li F, Squillace RM, Parillon LE, Greenfield MT, Miller DP, Qi J, Thomas RM, Wang Y, Xu Y, Miret JJ, Shakespeare WC, Zhu X, Dalgarno DC. Novel Small Molecule Inhibitors of Choline Kinase Identified by Fragment-Based Drug Discovery. J Med Chem 2016; 59:671-86. [PMID: 26700752 DOI: 10.1021/acs.jmedchem.5b01552] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Choline kinase α (ChoKα) is an enzyme involved in the synthesis of phospholipids and thereby plays key roles in regulation of cell proliferation, oncogenic transformation, and human carcinogenesis. Since several inhibitors of ChoKα display antiproliferative activity in both cellular and animal models, this novel oncogene has recently gained interest as a promising small molecule target for cancer therapy. Here we summarize our efforts to further validate ChoKα as an oncogenic target and explore the activity of novel small molecule inhibitors of ChoKα. Starting from weakly binding fragments, we describe a structure based lead discovery approach, which resulted in novel highly potent inhibitors of ChoKα. In cancer cell lines, our lead compounds exhibit a dose-dependent decrease of phosphocholine, inhibition of cell growth, and induction of apoptosis at low micromolar concentrations. The druglike lead series presented here is optimizable for improvements in cellular potency, drug target residence time, and pharmacokinetic parameters. These inhibitors may be utilized not only to further validate ChoKα as antioncogenic target but also as novel chemical matter that may lead to antitumor agents that specifically interfere with cancer cell metabolism.
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Affiliation(s)
- Stephan G Zech
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Anna Kohlmann
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Tianjun Zhou
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Feng Li
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Rachel M Squillace
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Lois E Parillon
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Matthew T Greenfield
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - David P Miller
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Jiwei Qi
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - R Mathew Thomas
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Yihan Wang
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Yongjin Xu
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Juan J Miret
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - William C Shakespeare
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - Xiaotian Zhu
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
| | - David C Dalgarno
- ARIAD Pharmaceuticals, Inc. , 26 Landsdowne Street, Cambridge, Massachusetts 02139, United States
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6
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Wang L, Jiang YL, Zhang JR, Zhou CZ, Chen Y. Structural and enzymatic characterization of the choline kinase LicA from Streptococcus pneumoniae. PLoS One 2015; 10:e0120467. [PMID: 25781969 PMCID: PMC4364537 DOI: 10.1371/journal.pone.0120467] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 01/22/2015] [Indexed: 01/07/2023] Open
Abstract
LicA plays a key role in the cell-wall phosphorylcholine biosynthesis of Streptococcus pneumonia. Here we determined the crystal structures of apo-form LicA at 1.94 Å and two complex forms LicA-choline and LicA-AMP-MES, at 2.01 and 1.45 Å resolution, respectively. The overall structure adopts a canonical protein kinase-like fold, with the active site located in the crevice of the N- and C-terminal domains. The three structures present distinct poses of the active site, which undergoes an open-closed-open conformational change upon substrate binding and product release. The structure analyses combined with mutageneses and enzymatic assays enabled us to figure out the key residues for the choline kinase activity of LicA. In addition, structural comparison revealed the loop between helices α7 and α8 might modulate the substrate specificity and catalytic activity. These findings shed light on the structure and mechanism of the prokaryotic choline kinase LicA, and might direct the rational design of novel anti-pneumococcal drugs.
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Affiliation(s)
- Lei Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China
| | - Yong-Liang Jiang
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,* E-mail: (YLJ); (YC)
| | - Jing-Ren Zhang
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing, 100084, People’s Republic of China
| | - Cong-Zhao Zhou
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China
| | - Yuxing Chen
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,* E-mail: (YLJ); (YC)
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7
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Megaconial congenital muscular dystrophy due to loss-of-function mutations in choline kinase β. Curr Opin Neurol 2014; 26:536-43. [PMID: 23945283 DOI: 10.1097/wco.0b013e328364c82d] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
PURPOSE OF REVIEW Recessive mutations in CHKB cause a megaconial congenital muscular dystrophy whose most characteristic feature is mitochondrial enlargement at the periphery of muscle fibers and loss of mitochondria in the center of muscle fibers. This review will summarize clinicopathological features, genetic cause, and biochemical abnormalities of the disease, trying to decipher the mechanism of this complex disorder. RECENT FINDINGS Since our report of CHKB mutations found in 15 cases with megaconial congenital muscular dystrophy from Japanese, Turkish, and British populations, we have further identified two British and one French patients. One African-American patient has also been reported by another group. All patients have relatively homogenous phenotype although severity varies to some extent. The peculiar distribution pattern of enlarged mitochondria on muscle section seems to be due to a compensatory mechanism after the elimination of functionally defective mitochondria by mitophagy. SUMMARY CHKB encodes choline kinase β, an enzyme that catalyzes the first de-novo biosynthetic step of phosphatidylcholine, the most abundant phospholipid in the eukaryotic membrane. The identification of a new muscle disease caused by the defect in phospholipid metabolism will pave the way for a novel biological pathway that connects phospholipid metabolism, mitochondria biology, and muscular dystrophy.
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8
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Gruber J, See Too WC, Wong MT, Lavie A, McSorley T, Konrad M. Balance of human choline kinase isoforms is critical for cell cycle regulation. FEBS J 2012; 279:1915-28. [DOI: 10.1111/j.1742-4658.2012.08573.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Miyake T, Parsons SJ. Functional interactions between Choline kinase α, epidermal growth factor receptor and c-Src in breast cancer cell proliferation. Oncogene 2011; 31:1431-41. [PMID: 21822308 PMCID: PMC3213328 DOI: 10.1038/onc.2011.332] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Epidermal growth factor receptor (EGFR) family members and c-Src are co-overexpressed in many cancers. The synergistic effect of EGFR and c-Src has been shown in the tumorigenesis of breast and other cancers. Reported mechanisms of synergy include transcriptional regulation by STAT5b and the regulation of cellular ATP production by mitochondrial protein COX II. Here, we report a new mechanism of EGFR-c-Src synergy through choline kinase α (CHKA). The first enzyme of the phosphatidyl choline production pathway, CHKA, is overexpressed in many cancers, and the product of the enzyme, phosphocholine, is also increased in tumor cells. In this report, we find that CHKA forms a complex with EGFR in a c-Src-dependent manner. Endogenous CHKA and EGFR co-immunoprecipitated from a variety of breast cancer cell lines and immortalized mammary epithelial cells. CHKA interacted with the EGFR kinase domain upon c-Src co-overexpression and was phosphorylated in a c-Src-dependent manner on Y197 and Y333. Overexpression of EGFR and c-Src increased total cellular activity and protein levels of CHKA. Mutation of CHKA Y197 and Y333 reduced complex formation, EGFR-dependent activation of CHKA enzyme activity and epidermal growth factor (EGF)-dependent DNA synthesis. Furthermore, small interfering RNA-mediated knockdown of CHKA in MCF-7 and MCF-10A cells reduced EGF-dependent cell proliferation. Together, these results strongly implicate a new c-Src-dependent link between CHKA and EGFR, which contributes to the regulation of cell proliferation and tumorigenesis.
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Affiliation(s)
- T Miyake
- Department of Microbiology and Cancer Center, University of Virginia Health System, Charlottesville, VA, USA
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Mitsuhashi S, Ohkuma A, Talim B, Karahashi M, Koumura T, Aoyama C, Kurihara M, Quinlivan R, Sewry C, Mitsuhashi H, Goto K, Koksal B, Kale G, Ikeda K, Taguchi R, Noguchi S, Hayashi Y, Nonaka I, Sher R, Sugimoto H, Nakagawa Y, Cox G, Topaloglu H, Nishino I. A congenital muscular dystrophy with mitochondrial structural abnormalities caused by defective de novo phosphatidylcholine biosynthesis. Am J Hum Genet 2011; 88:845-851. [PMID: 21665002 DOI: 10.1016/j.ajhg.2011.05.010] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 04/21/2011] [Accepted: 05/10/2011] [Indexed: 01/16/2023] Open
Abstract
Congenital muscular dystrophy is a heterogeneous group of inherited muscle diseases characterized clinically by muscle weakness and hypotonia in early infancy. A number of genes harboring causative mutations have been identified, but several cases of congenital muscular dystrophy remain molecularly unresolved. We examined 15 individuals with a congenital muscular dystrophy characterized by early-onset muscle wasting, mental retardation, and peculiar enlarged mitochondria that are prevalent toward the periphery of the fibers but are sparse in the center on muscle biopsy, and we have identified homozygous or compound heterozygous mutations in the gene encoding choline kinase beta (CHKB). This is the first enzymatic step in a biosynthetic pathway for phosphatidylcholine, the most abundant phospholipid in eukaryotes. In muscle of three affected individuals with nonsense mutations, choline kinase activities were undetectable, and phosphatidylcholine levels were decreased. We identified the human disease caused by disruption of a phospholipid de novo biosynthetic pathway, demonstrating the pivotal role of phosphatidylcholine in muscle and brain.
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Aoyama C, Ishidate K, Sugimoto H, Vance DE. Induction of choline kinase alpha by carbon tetrachloride (CCl4) occurs via increased binding of c-jun to an AP-1 element. Biochim Biophys Acta Mol Cell Biol Lipids 2007; 1771:1148-55. [PMID: 17728180 DOI: 10.1016/j.bbalip.2007.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 06/30/2007] [Accepted: 07/14/2007] [Indexed: 10/23/2022]
Abstract
The mechanism by which treatment of mice with CCl4 induces an increase in choline kinase alpha has been investigated. Nuclear run on assays demonstrated a major increase in the transcript for choline kinase alpha in livers from mice 3 h and 6 h after administration of CCl4 compared to vehicle (olive oil). 5'deletion analyses of choline kinase alpha promoter-luciferase constructs expressed in Hepa-1 cells identified a promoter element between -875 and -866 that was nearly identical to an AP-1 consensus site. Mutation of this AP-1 site caused a striking decrease in the expression of choline kinase alpha promoter-luciferase constructs. Electromobility shift assays with nuclear extracts from mouse liver demonstrated that c-Jun, but not c-fos, bound oligonucleotides with the AP-1 site. The amount of c-jun bound was greatly increased when hepatic nuclear extracts from mice treated with CCl4 were used. Chromatin immunoprecipitation assays confirmed that c-jun binds to the choline kinase alpha promoter. The results from these studies provide strong evidence that the choline kinase alpha promoter has a distal element (-875/-867) that binds c-jun and the binding of c-jun is enhanced by treatment with CCl4.
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Affiliation(s)
- Chieko Aoyama
- Department of Biochemistry and the Canadian Institutes of Health Research Group on Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta, Canada T6G 2S2.
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Malito E, Sekulic N, Too WCS, Konrad M, Lavie A. Elucidation of human choline kinase crystal structures in complex with the products ADP or phosphocholine. J Mol Biol 2006; 364:136-51. [PMID: 17007874 PMCID: PMC1885479 DOI: 10.1016/j.jmb.2006.08.084] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 08/25/2006] [Accepted: 08/28/2006] [Indexed: 10/24/2022]
Abstract
Choline kinase, responsible for the phosphorylation of choline to phosphocholine as the first step of the CDP-choline pathway for the biosynthesis of phosphatidylcholine, has been recognized as a new target for anticancer therapy. Crystal structures of human choline kinase in its apo, ADP and phosphocholine-bound complexes, respectively, reveal the molecular details of the substrate binding sites. ATP binds in a cavity where residues from both the N and C-terminal lobes contribute to form a cleft, while the choline-binding site constitutes a deep hydrophobic groove in the C-terminal domain with a rim composed of negatively charged residues. Upon binding of choline, the enzyme undergoes conformational changes independently affecting the N-terminal domain and the ATP-binding loop. From this structural analysis and comparison with other kinases, and from mutagenesis data on the homologous Caenorhabditis elegans choline kinase, a model of the ternary ADP.phosphocholine complex was built that reveals the molecular basis for the phosphoryl transfer activity of this enzyme.
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Affiliation(s)
- Enrico Malito
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois, 60607
| | - Nikolina Sekulic
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois, 60607
| | - Wei Cun See Too
- Department of Molecular Genetics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany, D-37077
| | - Manfred Konrad
- Department of Molecular Genetics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany, D-37077
| | - Arnon Lavie
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois, 60607
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