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Zhang S, Yamada S, Park S, Klepinin A, Kaambre T, Terzic A, Dzeja P. Adenylate kinase AK2 isoform integral in embryo and adult heart homeostasis. Biochem Biophys Res Commun 2021; 546:59-64. [PMID: 33571905 DOI: 10.1016/j.bbrc.2021.01.097] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 01/28/2021] [Indexed: 12/21/2022]
Abstract
Adenylate kinase2 (AK2) catalyzes trans-compartmental nucleotide exchange, but the functional implications of this mitochondrial intermembrane isoform is only partially understood. Here, transgenic AK2-/- null homozygosity was lethal early in embryo, indicating a mandatory role for intact AK2 in utero development. In the adult, conditional organ-specific ablation of AK2 precipitated abrupt heart failure with Krebs cycle and glycolytic metabolite buildup, suggesting a vital contribution to energy demanding cardiac performance. Depressed pump function recovered to pre-deletion levels overtime, suggestive of an adaptive response. Compensatory upregulation of phosphotransferase AK1, AK3, AK4 isozymes, creatine kinase isoforms, and hexokinase, along with remodeling of cell cycle/growth genes and mitochondrial ultrastructure supported organ rescue. Taken together, the requirement of AK2 in early embryonic stages, and the immediate collapse of heart performance in the AK2-deficient postnatal state underscore a primordial function of the AK2 isoform. Unsalvageable in embryo, loss of AK2 in the adult heart was recoverable, underscoring an AK2-integrated bioenergetics system with innate plasticity to maintain homeostasis on demand.
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Affiliation(s)
- Song Zhang
- Department of Cardiovascular Medicine and Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, 55905, USA
| | - Satsuki Yamada
- Department of Cardiovascular Medicine and Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, 55905, USA; Division of Geriatric Medicine and Gerontology, Department of Medicine, Mayo Clinic, Rochester, MN, 55905, USA
| | - Sungjo Park
- Department of Cardiovascular Medicine and Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, 55905, USA
| | - Aleksandr Klepinin
- Department of Cardiovascular Medicine and Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, 55905, USA; Laboratory of Chemical Biology, National Institute of Chemical Physics and Biophysics, Tallinn, 12618, Estonia
| | - Tuuli Kaambre
- Laboratory of Chemical Biology, National Institute of Chemical Physics and Biophysics, Tallinn, 12618, Estonia
| | - Andre Terzic
- Department of Cardiovascular Medicine and Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, 55905, USA; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA; Department of Clinical Genomics, Mayo Clinic, Rochester, MN, 55905, USA.
| | - Petras Dzeja
- Department of Cardiovascular Medicine and Center for Regenerative Medicine, Mayo Clinic, Rochester, MN, 55905, USA.
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Li WR, Shi QS, Dai HQ, Liang Q, Xie XB, Huang XM, Zhao GZ, Zhang LX. Antifungal activity, kinetics and molecular mechanism of action of garlic oil against Candida albicans. Sci Rep 2016; 6:22805. [PMID: 26948845 PMCID: PMC4779998 DOI: 10.1038/srep22805] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 02/19/2016] [Indexed: 11/21/2022] Open
Abstract
The antifungal activity, kinetics, and molecular mechanism of action of garlic oil against Candida albicans were investigated in this study using multiple methods. Using the poisoned food technique, we determined that the minimum inhibitory concentration of garlic oil was 0.35 μg/mL. Observation by transmission electron microscopy indicated that garlic oil could penetrate the cellular membrane of C. albicans as well as the membranes of organelles such as the mitochondria, resulting in organelle destruction and ultimately cell death. RNA sequencing analysis showed that garlic oil induced differential expression of critical genes including those involved in oxidation-reduction processes, pathogenesis, and cellular response to drugs and starvation. Moreover, the differentially expressed genes were mainly clustered in 19 KEGG pathways, representing vital cellular processes such as oxidative phosphorylation, the spliceosome, the cell cycle, and protein processing in the endoplasmic reticulum. In addition, four upregulated proteins selected after two-dimensional fluorescence difference in gel electrophoresis (2D-DIGE) analysis were identified with high probability by mass spectrometry as putative cytoplasmic adenylate kinase, pyruvate decarboxylase, hexokinase, and heat shock proteins. This is suggestive of a C. albicans stress responses to garlic oil treatment. On the other hand, a large number of proteins were downregulated, leading to significant disruption of the normal metabolism and physical functions of C. albicans.
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Affiliation(s)
- Wen-Ru Li
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, 510070, China
| | - Qing-Shan Shi
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, 510070, China
| | - Huan-Qin Dai
- Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing, 100101, China
| | - Qing Liang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, 510070, China
| | - Xiao-Bao Xie
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, 510070, China
| | - Xiao-Mo Huang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, 510070, China
| | - Guang-Ze Zhao
- Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing, 100101, China
| | - Li-Xin Zhang
- Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing, 100101, China
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Rissone A, Weinacht KG, la Marca G, Bishop K, Giocaliere E, Jagadeesh J, Felgentreff K, Dobbs K, Al-Herz W, Jones M, Chandrasekharappa S, Kirby M, Wincovitch S, Simon KL, Itan Y, DeVine A, Schlaeger T, Schambach A, Sood R, Notarangelo LD, Candotti F. Reticular dysgenesis-associated AK2 protects hematopoietic stem and progenitor cell development from oxidative stress. ACTA ACUST UNITED AC 2015; 212:1185-202. [PMID: 26150473 PMCID: PMC4516804 DOI: 10.1084/jem.20141286] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 06/01/2015] [Indexed: 12/23/2022]
Abstract
Rissone et al. demonstrate that adenylate kinase AK2, an enzyme mutated in reticular dysgenesis (RD) in humans, prevents oxidative stress during hematopoiesis. Using a zebrafish model, as well as induced pluripotent stem cells derived from an RD patient, they find that AK2 deficiency affects hematopoietic stem and progenitor development with increased oxidative stress. Antioxidant treatment rescues the hematopoietic phenotypes. Adenylate kinases (AKs) are phosphotransferases that regulate the cellular adenine nucleotide composition and play a critical role in the energy homeostasis of all tissues. The AK2 isoenzyme is expressed in the mitochondrial intermembrane space and is mutated in reticular dysgenesis (RD), a rare form of severe combined immunodeficiency (SCID) in humans. RD is characterized by a maturation arrest in the myeloid and lymphoid lineages, leading to early onset, recurrent, and overwhelming infections. To gain insight into the pathophysiology of RD, we studied the effects of AK2 deficiency using the zebrafish model and induced pluripotent stem cells (iPSCs) derived from fibroblasts of an RD patient. In zebrafish, Ak2 deficiency affected hematopoietic stem and progenitor cell (HSPC) development with increased oxidative stress and apoptosis. AK2-deficient iPSCs recapitulated the characteristic myeloid maturation arrest at the promyelocyte stage and demonstrated an increased AMP/ADP ratio, indicative of an energy-depleted adenine nucleotide profile. Antioxidant treatment rescued the hematopoietic phenotypes in vivo in ak2 mutant zebrafish and restored differentiation of AK2-deficient iPSCs into mature granulocytes. Our results link hematopoietic cell fate in AK2 deficiency to cellular energy depletion and increased oxidative stress. This points to the potential use of antioxidants as a supportive therapeutic modality for patients with RD.
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Affiliation(s)
- Alberto Rissone
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Katja Gabriele Weinacht
- Division of Hematology/Oncology and Division of Immunology, Boston Children's Hospital, Boston, MA 02115 Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115
| | - Giancarlo la Marca
- Department of Neurosciences, Psychology, Pharmacology, and Child Health, University of Florence, 51039 Florence, Italy Meyer Children's University Hospital, 50141 Florence, Italy
| | - Kevin Bishop
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | | | - Jayashree Jagadeesh
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Kerstin Felgentreff
- Division of Hematology/Oncology and Division of Immunology, Boston Children's Hospital, Boston, MA 02115
| | - Kerry Dobbs
- Division of Hematology/Oncology and Division of Immunology, Boston Children's Hospital, Boston, MA 02115
| | - Waleed Al-Herz
- Department of Pediatrics, Faculty of Medicine, Kuwait University, 13110 Kuwait City, Kuwait Allergy and Clinical Immunology Unit, Pediatric Department, Al-Sabah Hospital, 70459 Kuwait City, Kuwait
| | - Marypat Jones
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Settara Chandrasekharappa
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Martha Kirby
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Stephen Wincovitch
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Karen Lyn Simon
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Yuval Itan
- St. Giles Laboratory of Human Genetics of Infectious Disease, Rockefeller Branch, The Rockefeller University, New York, NY 10065
| | - Alex DeVine
- Division of Hematology/Oncology and Division of Immunology, Boston Children's Hospital, Boston, MA 02115
| | - Thorsten Schlaeger
- Division of Hematology/Oncology and Division of Immunology, Boston Children's Hospital, Boston, MA 02115
| | - Axel Schambach
- Division of Hematology/Oncology and Division of Immunology, Boston Children's Hospital, Boston, MA 02115 Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Raman Sood
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892 Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Luigi D Notarangelo
- Division of Hematology/Oncology and Division of Immunology, Boston Children's Hospital, Boston, MA 02115 Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138
| | - Fabio Candotti
- Disorders of Immunity Section, Genetics and Molecular Biology Branch; Zebrafish Core and Oncogenesis and Development Section, Translational and Functional Genomics Branch; Genomics Core, Cancer Genetics and Comparative Genomics Branch; Division of Intramural Research Flow Cytometry Core; and Cytogenetics and Microscopy Core, Genetic Disease Research Branch; National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892 Division of Immunology and Allergy, University Hospital of Lausanne, 1011 Lausanne, Switzerland
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Mechanisms and physiological impact of the dual localization of mitochondrial intermembrane space proteins. Biochem Soc Trans 2015; 42:952-8. [PMID: 25109985 DOI: 10.1042/bst20140104] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Eukaryotic cells developed diverse mechanisms to guide proteins to more than one destination within the cell. Recently, the proteome of the IMS (intermembrane space) of mitochondria of yeast cells was identified showing that approximately 20% of all soluble IMS proteins are dually localized to the IMS, as well as to other cellular compartments. Half of these dually localized proteins are important for oxidative stress defence and the other half are involved in energy homoeostasis. In the present review, we discuss the mechanisms leading to the dual localization of IMS proteins and the implications for mitochondrial function.
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Differential expression of adenine nucleotide converting enzymes in mitochondrial intermembrane space: a potential role of adenylate kinase isozyme 2 in neutrophil differentiation. PLoS One 2014; 9:e89916. [PMID: 24587121 PMCID: PMC3934953 DOI: 10.1371/journal.pone.0089916] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 01/29/2014] [Indexed: 02/06/2023] Open
Abstract
Adenine nucleotide dynamics in the mitochondrial intermembrane space (IMS) play a key role in oxidative phosphorylation. In a previous study, Drosophila adenylate kinase isozyme 2 (Dak2) knockout was reported to cause developmental lethality at the larval stage in Drosophila melanogaster. In addition, two other studies reported that AK2 is a responsible gene for reticular dysgenesis (RD), a human disease that is characterized by severe combined immunodeficiency and deafness. Therefore, mitochondrial AK2 may play an important role in hematopoietic differentiation and ontogenesis. Three additional adenine nucleotide metabolizing enzymes, including mitochondrial creatine kinases (CKMT1 and CKMT2) and nucleoside diphosphate kinase isoform D (NDPK-D), have been found in IMS. Although these kinases generate ADP for ATP synthesis, their involvement in RD remains unclear and still an open question. In this study, mRNA and protein expressions of these mitochondrial kinases were firstly examined in mouse ES cells, day 8 embryos, and 7-week-old adult mice. It was found that their expressions are spatiotemporally regulated, and Ak2 is exclusively expressed in bone marrow, which is a major hematopoietic tissue in adults. In subsequent experiments, we identified increased expression of both AK2 and CKMT1 during macrophage differentiation and exclusive production of AK2 during neutrophil differentiation using HL-60 cells as an in vitro model of hematopoietic differentiation. Furthermore, AK2 knockdown specifically inhibited neutrophil differentiation without affecting macrophage differentiation. These data suggest that AK2 is indispensable for neutrophil differentiation and indicate a possible causative link between AK2 deficiency and neutropenia in RD.
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Long-lasting effects of oxy- and sulfoanalogues of L-arginine on enzyme actions. JOURNAL OF AMINO ACIDS 2013; 2013:407616. [PMID: 24282631 PMCID: PMC3824642 DOI: 10.1155/2013/407616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 08/20/2013] [Accepted: 09/15/2013] [Indexed: 11/22/2022]
Abstract
Arginine residues are very important for the structure of proteins and their action. Arginine is essential for many natural processes because it has unique ionizable group under physiological conditions. Numerous mimetics of arginine were synthesized and their biological effects were evaluated, but the mechanisms of actions are still unknown.
The aim of this study is to see if oxy- and sulfoanalogues of arginine can be recognized by human arginyl-tRNA synthetase (HArgS)—an enzyme responsible for coupling of L-arginine with its cognate tRNA in a two-step catalytic reaction. We make use of modeling and docking studies of adenylate kinase (ADK) to reveal the effects produced by the incorporation of the arginine mimetics on the structure of ADK and its action. Three analogues of arginine, L-canavanine (Cav), L-norcanavanine (NCav), and L-sulfoarginine (sArg), can be recognized as substrates of HArgS when incorporated in different peptide and protein sequences instead of L-arginine. Mutation in the enzyme active center by arginine mimetics leads to conformational changes, which produce a decrease the rate of the enzyme catalyzed reaction and even a loss of enzymatic action. All these observations could explain the long-lasting nature of the effects of the arginine analogues.
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Chen RP, Liu CY, Shao HL, Zheng WW, Wang JX, Zhao XF. Adenylate kinase 2 (AK2) promotes cell proliferation in insect development. BMC Mol Biol 2012; 13:31. [PMID: 23020757 PMCID: PMC3583204 DOI: 10.1186/1471-2199-13-31] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 09/20/2012] [Indexed: 11/25/2022] Open
Abstract
Background Adenylate kinase 2 (AK2) is a phosphotransferase that catalyzes the reversible reaction 2ADP(GDP) ↔ ATP(GTP) + AMP and influences cellular energy homeostasis. However, the role of AK2 in regulating cell proliferation remains unclear because AK2 has been reported to be involved in either cell proliferation or cell apoptosis in different cell types of various organisms. Results This study reports AK2 promotion of cell proliferation using the lepidopteran insect Helicoverpa armigera and its epidermal cell line HaEpi as models. Western blot analysis indicates that AK2 constitutively expresses in various tissues during larval development. Immunocytochemistry analysis indicates that AK2 localizes in the mitochondria. The recombinant expressed AK2 in E. coli promotes cell growth and viability of HaEpi cell line by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. AK2 knockdown in larvae by RNA interference causes larval growth defects, including body weight decrease and development delay. AK2 knockdown in larvae also decreases the number of circulating haemocytes. The mechanism for such effects might be the suppression of gene transcription involved in insect development caused by AK2 knockdown. Conclusion These results show that AK2 regulates cell growth, viability, and proliferation in insect growth and development.
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Affiliation(s)
- Ru-Ping Chen
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, Shandong University, Shandong, Jinan, 250100, China
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Abstract
The enzyme fumarase is a conserved protein in all organisms with regard to its sequence, structure and function. This enzyme participates in the tricarboxylic acid cycle in mitochondria which is essential for cellular respiration in eukaryotes. However, a common theme conserved from yeast to humans is the existence of a cytosolic form of fumarase; hence this protein is dual localized. We have coined identical (or nearly identical) proteins situated in different subcellular locations 'echoforms' or 'echoproteins'. Fumarase was the first example of a dual localized protein whose mechanism of distribution was found to be based on a single translation product. Consequently, fumarase has become a paradigm for three unique eukaryotic cellular phenomena related to protein dual localization: (a) distribution between mitochondria and the cytoplasm involves reverse translocation; (b) targeting to mitochondria involves translation coupled import; and (c) there are two echoforms possessing distinct functions in the respective subcellular compartments. Here we describe and discuss these fumarase related phenomena and in addition point out approaches for studying dual function of distributed proteins, in particular compartment-specific depletion. In the case of fumarase, the cytoplasmic function was only recently discovered; the enzyme was found to participate in the cellular response to DNA double strand breaks. Strikingly, upon DNA damage the protein is transported from the cytosol to the nucleus, where by virtue of its enzymatic activity it participates in the DNA damage response.
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Affiliation(s)
- Ohad Yogev
- Department of Microbiology and Molecular Genetics, IMRIC, Faculty of Medicine, Hebrew University, Jerusalem, Israel
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9
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ACoM: A classification method for elementary flux modes based on motif finding. Biosystems 2011; 103:410-9. [DOI: 10.1016/j.biosystems.2010.12.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2009] [Revised: 11/15/2010] [Accepted: 12/01/2010] [Indexed: 11/19/2022]
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Dzeja P, Terzic A. Adenylate kinase and AMP signaling networks: metabolic monitoring, signal communication and body energy sensing. Int J Mol Sci 2009; 10:1729-1772. [PMID: 19468337 PMCID: PMC2680645 DOI: 10.3390/ijms10041729] [Citation(s) in RCA: 318] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 03/26/2009] [Accepted: 04/02/2009] [Indexed: 12/20/2022] Open
Abstract
Adenylate kinase and downstream AMP signaling is an integrated metabolic monitoring system which reads the cellular energy state in order to tune and report signals to metabolic sensors. A network of adenylate kinase isoforms (AK1-AK7) are distributed throughout intracellular compartments, interstitial space and body fluids to regulate energetic and metabolic signaling circuits, securing efficient cell energy economy, signal communication and stress response. The dynamics of adenylate kinase-catalyzed phosphotransfer regulates multiple intracellular and extracellular energy-dependent and nucleotide signaling processes, including excitation-contraction coupling, hormone secretion, cell and ciliary motility, nuclear transport, energetics of cell cycle, DNA synthesis and repair, and developmental programming. Metabolomic analyses indicate that cellular, interstitial and blood AMP levels are potential metabolic signals associated with vital functions including body energy sensing, sleep, hibernation and food intake. Either low or excess AMP signaling has been linked to human disease such as diabetes, obesity and hypertrophic cardiomyopathy. Recent studies indicate that derangements in adenylate kinase-mediated energetic signaling due to mutations in AK1, AK2 or AK7 isoforms are associated with hemolytic anemia, reticular dysgenesis and ciliary dyskinesia. Moreover, hormonal, food and antidiabetic drug actions are frequently coupled to alterations of cellular AMP levels and associated signaling. Thus, by monitoring energy state and generating and distributing AMP metabolic signals adenylate kinase represents a unique hub within the cellular homeostatic network.
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Affiliation(s)
- Petras Dzeja
- Author to whom correspondence should be addressed; E-mail:
(P.D.)
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11
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Yogev O, Karniely S, Pines O. Translation-coupled Translocation of Yeast Fumarase into Mitochondria in Vivo. J Biol Chem 2007; 282:29222-9. [PMID: 17666392 DOI: 10.1074/jbc.m704201200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fumarase represents proteins that cannot be imported into mitochondria after the termination of translation (post-translationally). Utilizing mitochondrial and cytosolic versions of the tobacco etch virus (TEV) protease, we show that mitochondrially targeted fumarase harboring a TEV protease recognition sequence is efficiently cleaved by the mitochondrial but not by the cytosolic TEV protease. Nonetheless, fumarase was readily cleaved by cytosolic TEV when its import into mitochondria was slowed down by either (i) disrupting the activity of the TOM complex, (ii) lowering the growth temperature, or (iii) reducing the inner membrane electrochemical potential. Accessibility of the fumarase nascent chain to TEV protease under such conditions was prevented by low cycloheximide concentrations, which impede translation. In addition, depletion of the ribosome-associated nascent polypeptide-associated complex (NAC) reduced the fumarase rate of translocation into mitochondria and exposed it to TEV cleavage in the cytosol. These results indicate that cytosolic exposure of the fumarase nascent chain depends on both translocation and translation rates, allowing us to discuss the possibility that import of fumarase into mitochondria occurs while the ribosome is still attached to the nascent chain.
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Affiliation(s)
- Ohad Yogev
- Department of Molecular Biology, Hebrew University Medical School, Jerusalem 91120, Israel
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Cao W, Haig-Ladewig L, Gerton GL, Moss SB. Adenylate Kinases 1 and 2 Are Part of the Accessory Structures in the Mouse Sperm Flagellum1. Biol Reprod 2006; 75:492-500. [PMID: 16790685 DOI: 10.1095/biolreprod.106.053512] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Proper sperm function depends on adequate ATP levels. In the mammalian flagellum, ATP is generated in the midpiece by oxidative respiration and in the principal piece by glycolysis. In locations where ATP is rapidly utilized or produced, adenylate kinases (AKs) maintain a constant adenylate energy charge by interconverting stoichiometric amounts of ATP and AMP with two ADP molecules. We previously identified adenylate kinase 1 and 2 (AK1 and AK2) by mass spectrometry as part of a mouse SDS-insoluble flagellar preparation containing the accessory structures (fibrous sheath, outer dense fibers, and mitochondrial sheath). A germ cell-specific cDNA encoding AK1 was characterized and found to contain a truncated 3' UTR and a different 5' UTR compared to the somatic Ak1 mRNA; however, it encoded an identical protein. Ak1 mRNA was upregulated during late spermiogenesis, a time when the flagellum is being assembled. AK1 was first seen in condensing spermatids and was associated with the outer microtubular doublets and outer dense fibers of sperm. This localization would allow the interconversion of ATP and ADP between the fibrous sheath where ATP is produced by glycolysis and the axonemal dynein ATPases where ATP is consumed. Ak2 mRNA was expressed at relatively low levels throughout spermatogenesis, and the protein was localized to the mitochondrial sheath in the sperm midpiece. AK1 and AK2 in the flagellar accessory structures provide a mechanism to buffer the adenylate energy charge for sperm motility.
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Affiliation(s)
- Wenlei Cao
- Center for Research on Reproduction and Women's Health, Department of Obstetrics and Gynecology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104, USA
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Karniely S, Regev-Rudzki N, Pines O. The presequence of fumarase is exposed to the cytosol during import into mitochondria. J Mol Biol 2006; 358:396-405. [PMID: 16530220 DOI: 10.1016/j.jmb.2006.02.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2006] [Revised: 02/07/2006] [Accepted: 02/09/2006] [Indexed: 11/28/2022]
Abstract
The majority of mitochondrial proteins can be imported into mitochondria following termination of their translation in the cytosol. Import of fumarase and several other proteins into mitochondria does not appear to occur post-translationally according to standard in vivo and in vitro assays. However, the nature of interaction between the translation and translocation apparatuses during import of these proteins is unknown. Therefore, a major question is whether the nascent chains of these proteins are exposed to the cytosol during import into mitochondria. We asked directly if the presequence of fumarase can be cleaved by externally added mitochondrial processing peptidase (MPP) during import, using an in vitro translation-translocation coupled reaction. The presequence of fumarase was cleaved by externally added MPP during import, indicating a lack of, or a loose physical connection between, the translation and translocation of this protein. Exchanging the authentic presequence of fumarase for that of the more efficient Su9-ATPase presequence reduced the exposure of fumarase precursors to externally added MPP en route to mitochondria. Therefore, exposure to cytosolic MPP is dependent on the presequence and not on the mature part of fumarase. On the other hand, following translation in the absence of mitochondria, the authentic fumarase presequence and that of Su9-ATPase become inaccessible to added MPP when attached to mature fumarase. Thus, folding of the mature portion of fumarase, which conceals the presequence, is the reason for its inability to be imported in classical post-translational assays. Another unique feature of fumarase is its distribution between the mitochondria and the cytosol. We show that in vivo the switch of the authentic presequence with that of Su9-ATPase caused more fumarase molecules to be localized to the mitochondria. A possible mechanism by which the cytosolic exposure, the targeting efficiency, and the subcellular distribution of fumarase are dictated by the presequence is discussed.
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Affiliation(s)
- Sharon Karniely
- Department of Molecular Biology, Hebrew University Medical School, Jerusalem 91120, Israel
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14
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Zuzuarregui A, Monteoliva L, Gil C, del Olmo ML. Transcriptomic and proteomic approach for understanding the molecular basis of adaptation of Saccharomyces cerevisiae to wine fermentation. Appl Environ Microbiol 2006; 72:836-47. [PMID: 16391125 PMCID: PMC1352203 DOI: 10.1128/aem.72.1.836-847.2006] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2005] [Accepted: 11/01/2005] [Indexed: 11/20/2022] Open
Abstract
Throughout alcoholic fermentation, Saccharomyces cerevisiae cells have to cope with several stress conditions that could affect their growth and viability. In addition, the metabolic activity of yeast cells during this process leads to the production of secondary compounds that contribute to the organoleptic properties of the resulting wine. Commercial strains have been selected during the last decades for inoculation into the must to carry out the alcoholic fermentation on the basis of physiological traits, but little is known about the molecular basis of the fermentative behavior of these strains. In this work, we present the first transcriptomic and proteomic comparison between two commercial strains with different fermentative behaviors. Our results indicate that some physiological differences between the fermentative behaviors of these two strains could be related to differences in the mRNA and protein profiles. In this sense, at the level of gene expression, we have found differences related to carbohydrate metabolism, nitrogen catabolite repression, and response to stimuli, among other factors. In addition, we have detected a relative increase in the abundance of proteins involved in stress responses (the heat shock protein Hsp26p, for instance) and in fermentation (in particular, the major cytosolic aldehyde dehydrogenase Ald6p) in the strain with better behavior during vinification. Moreover, in the case of the other strain, higher levels of enzymes required for sulfur metabolism (Cys4p, Hom6p, and Met22p) are observed, which could be related to the production of particular organoleptic compounds or to detoxification processes.
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Affiliation(s)
- Aurora Zuzuarregui
- Departament de Bioquímica i Biologia Molecular, Facultat de Ciències Biològiques, Universitat de València, Dr. Moliner, 50, E-46100 Burjassot (Valencia), Spain
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15
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Ginger ML, Ngazoa ES, Pereira CA, Pullen TJ, Kabiri M, Becker K, Gull K, Steverding D. Intracellular Positioning of Isoforms Explains an Unusually Large Adenylate Kinase Gene Family in the Parasite Trypanosoma brucei. J Biol Chem 2005; 280:11781-9. [PMID: 15657034 DOI: 10.1074/jbc.m413821200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Adenylate kinases occur classically as cytoplasmic and mitochondrial enzymes, but the expression of seven adenylate kinases in the flagellated protozoan parasite Trypanosoma brucei (order, Kinetoplastida; family, Trypanosomatidae) easily exceeds the number of isoforms previously observed within a single cell and raises questions as to their location and function. We show that a requirement to target adenylate kinase into glycosomes, which are unique kinetoplastid-specific microbodies of the peroxisome class in which many reactions of carbohydrate metabolism are compartmentalized, and two different flagellar structures as well as cytoplasm and mitochondrion explains the expansion of this gene family in trypanosomes. The three isoforms that are selectively built into either the flagellar axoneme or the extra-axonemal paraflagellar rod, which is essential for motility, all contain long N-terminal extensions. Biochemical analysis of the only short form trypanosome adenylate kinase revealed that this enzyme catalyzes phosphotransfer of gamma-phosphate from ATP to AMP, CMP, and UMP acceptors; its high activity and specificity toward CMP is likely to reflect an adaptation to very low intracellular cytidine nucleotide pools. Analysis of some of the phosphotransfer network using RNA interference suggests considerable complexity within the homeostasis of cellular energetics. The anchoring of specific adenylate kinases within two distinct flagellar structures provides a paradigm for metabolic organization and efficiency in other flagellates.
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Affiliation(s)
- Michael L Ginger
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE, United Kingdom
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16
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Abstract
Precise coupling of spatially separated intracellular ATP-producing and ATP-consuming processes is fundamental to the bioenergetics of living organisms, ensuring a fail-safe operation of the energetic system over a broad range of cellular functional activities. Here, we provide an overview of the role of spatially arranged enzymatic networks, catalyzed by creatine kinase, adenylate kinase, carbonic anhydrase and glycolytic enzymes, in efficient high-energy phosphoryl transfer and signal communication in the cell. Studies of transgenic creatine kinase and adenylate kinase deficient mice, along with pharmacological targeting of individual enzymes, have revealed the importance of near-equilibrium reactions in the dissipation of metabolite gradients and communication of energetic signals to distinct intracellular compartments, including the cell nucleus and membrane metabolic sensors. Enzymatic capacities, isoform distribution and the dynamics of net phosphoryl flux through the integrated phosphotransfer systems tightly correlate with cellular functions, indicating a critical role of such networks in efficient energy transfer and distribution, thereby securing the cellular economy and energetic homeostasis under stress.
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Affiliation(s)
- Petras P Dzeja
- Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Mayo Foundation, Rochester, MN 55905, USA.
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17
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Angermayr M, Oechsner U, Gregor K, Schroth GP, Bandlow W. Transcription initiation in vivo without classical transactivators: DNA kinks flanking the core promoter of the housekeeping yeast adenylate kinase gene, AKY2, position nucleosomes and constitutively activate transcription. Nucleic Acids Res 2002; 30:4199-207. [PMID: 12364598 PMCID: PMC140550 DOI: 10.1093/nar/gkf551] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2002] [Revised: 07/26/2002] [Accepted: 08/13/2002] [Indexed: 11/13/2022] Open
Abstract
The housekeeping gene of the major adenylate kinase in Saccharomyces cerevisiae (AKY2, ADK1) is constitutively transcribed at a moderate level. The promoter has been dissected in order to define elements that effect constitutive transcription. Initiation of mRNA synthesis at the AKY2 promoter is shown to be mediated by a non-canonic core promoter, (TA)(6). Nucleotide sequences 5' of this element only marginally affect transcription suggesting that promoter activation can dispense with transactivators and essentially involves basal transcription. We show that the core promoter of AKY2 is constitutively kept free of nucleosomes. Analyses of permutated AKY2 promoter DNA revealed the presence of bent DNA. DNA structure analysis by computer and by mutation identified two kinks flanking an interstitial stretch of 65 bp of moderately bent core promoter DNA. Kinked DNA is likely incompatible with packaging into nucleosomes and responsible for positioning nucleosomes at the flanks allowing unimpeded access of the basal transcription machinery to the core promoter. The data show that in yeast, constitutive gene expression can dispense with classical transcriptional activator proteins, if two prerequisites are met: (i) the core promoter is kept free of nucleosomes; this can be due to structural properties of the DNA as an alternative to chromatin remodeling factors; and (ii) the core promoter is pre-bent to allow a high rate of basal transcription initiation.
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Affiliation(s)
- Michaela Angermayr
- Department Biologie I, Bereich Genetik, Ludwig-Maximilians-Universität München, Maria-Ward-Strasse 1a, D-80638 Munich, Germany.
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18
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Schricker R, Angermayr M, Strobel G, Klinke S, Korber D, Bandlow W. Redundant mitochondrial targeting signals in yeast adenylate kinase. J Biol Chem 2002; 277:28757-64. [PMID: 12045196 DOI: 10.1074/jbc.m201561200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Yeast adenylate kinase (Aky2p, Adk1p) occurs simultaneously in cytoplasm and mitochondrial intermembrane space. It has no cleavable mitochondrial targeting sequence, and the signal for mitochondrial import and submitochondrial sorting is largely unknown. The extreme N terminus of Aky2p is able to direct cytoplasmic passengers to mitochondria. However, an Aky2 mutant lacking this sequence is imported with about the same efficiency as the wild type. To identify possible import-relevant information in the interior, parts of Aky2p were exchanged by homologous in vitro recombination for the respective segments of the purely cytoplasmic isozyme, Ura6p. Import studies revealed an internal region of about 40 amino acids, which was sufficient to direct the chimera to mitochondria but not for correct submitochondrial sorting. The respective Ura6p hybrid was arrested in the mitochondrial membrane at a position where it was inaccessible to protease but was released by alkaline extraction, suggesting that it had entered an import channel and passed the initial steps of recognition and uptake. Site-specific mutations within the presumptive address-specifying segment identified the amphipathic helix 5. A Ura6 mutant protein in which helix 5 had been replaced with the respective sequence from Aky2p was imported, and this address sequence cooperates with the N terminus in the respective double mutant in a synergistic fashion.
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Affiliation(s)
- Roland Schricker
- Department Biologie I, Bereich Genetik, Ludwig Maximilians Universität München, Maria-Ward-Strasse 1a, D-80638 Munich, Germany
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19
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Dzeja PP, Bortolon R, Perez-Terzic C, Holmuhamedov EL, Terzic A. Energetic communication between mitochondria and nucleus directed by catalyzed phosphotransfer. Proc Natl Acad Sci U S A 2002; 99:10156-61. [PMID: 12119406 PMCID: PMC126640 DOI: 10.1073/pnas.152259999] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Exchange of information between the nucleus and cytosol depends on the metabolic state of the cell, yet the energy-supply pathways to the nuclear compartment are unknown. Here, the energetics of nucleocytoplasmic communication was determined by imaging import of a constitutive nuclear protein histone H1. Translocation of H1 through nuclear pores in cardiac cells relied on ATP supplied by mitochondrial oxidative phosphorylation, but not by glycolysis. Although mitochondria clustered around the nucleus, reducing the distance for energy transfer, simple nucleotide diffusion was insufficient to meet the energetic demands of nuclear transport. Rather, the integrated phosphotransfer network was required for delivery of high-energy phosphoryls from mitochondria to the nucleus. In neonatal cardiomyocytes with low creatine kinase activity, inhibition of adenylate kinase-catalyzed phosphotransfer abolished nuclear import. With deficient adenylate kinase, nucleoside diphosphate kinase, which secures phosphoryl exchange between ATP and GTP, was unable to sustain nuclear import. Up-regulation of creatine kinase phosphotransfer, to mimic metabolic conditions of adult cardiac cells, rescued H1 import, suggesting a developmental plasticity of the cellular energetic system. Thus, mitochondrial oxidative phosphorylation coupled with phosphotransfer relays provides an efficient energetic unit in support of nuclear transport.
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Affiliation(s)
- Petras P Dzeja
- Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
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20
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Strobel G, Zollner A, Angermayr M, Bandlow W. Competition of spontaneous protein folding and mitochondrial import causes dual subcellular location of major adenylate kinase. Mol Biol Cell 2002; 13:1439-48. [PMID: 12006643 PMCID: PMC111117 DOI: 10.1091/mbc.01-08-0396] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Sorting of cytoplasmically synthesized proteins to their target compartments usually is highly efficient so that cytoplasmic precursor pools are negligible and a particular gene product occurs at one subcellular location only. Yeast major adenylate kinase (Adk1p/Aky2p) is one prominent exception to this rule. In contrast to most mitochondrial proteins, only a minor fraction (6-8%) is taken up into the mitochondrial intermembrane space, whereas the bulk of the protein remains in the cytosol in sequence-identical form. We demonstrate that Adk1p/Aky2p uses a novel mechanism for subcellular partitioning between cytoplasm and mitochondria, which is based on competition between spontaneous protein folding and mitochondrial targeting and import. Folding is spontaneous and rapid and can dispense with molecular chaperons. After denaturation, enzymatic activity of Adk1p/Aky2p returns within a few minutes and, once folded, the protein is thermally and proteolytically very stable. In an uncoupled cell-free organellar import system, uptake of Adk1p/Aky2p is negligible, but can be improved by previous chaotropic denaturation. Import ensues independently of Hsp70 or membrane potential. Thus, nascent Adk1p/Aky2p has two options: either it is synthesized to completion and folds into an enzymatically active import-incompetent conformation that remains in the cytosol; or, during synthesis and before commencement of significant tertiary structure formation, it reaches a mitochondrial surface receptor and is internalized.
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Affiliation(s)
- Gertrud Strobel
- Institut für Genetik und Mikrobiologie der Universität München, D-80638 Munich, Germany
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21
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Angermayr M, Strobel G, Zollner A, Korber D, Bandlow W. Two parameters improve efficiency of mitochondrial uptake of adenylate kinase: decreased folding velocity and increased propensity of N-terminal alpha-helix formation. FEBS Lett 2001; 508:427-32. [PMID: 11728466 DOI: 10.1016/s0014-5793(01)03122-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The long isoform of eukaryotic adenylate kinase has a dual subcellular location in the cytoplasm and in the mitochondrial intermembrane space. Protein sequences and modifications are identical in both locations. In yeast, the bulk of the major form of adenylate kinase (Aky2p) is in the cytoplasm and, in the steady state, only 5-8% is sorted to the mitochondrial intermembrane space. Since the reasons for exclusion from mitochondrial import are unclear, we have constructed aky2 mutants with elevated mitochondrial uptake efficiency of Aky2p in vivo and in vitro. We have analyzed the effect of the mutations on secondary structure prediction in silico and have tested folding velocity and folding stability. One type of mutants displayed decreased proteolytic stability and retarded renaturation kinetics after chaotropic denaturation implying that deterioration of folding leads to prolonged presentation of target information to mitochondrial import receptors, thereby effecting improved uptake. In a second type of mutants, increased import efficiency was correlated with an increased probability of formation of an alpha-helix with increased amphipathic moment at the N-terminus suggesting that targeting interactions with mitochondrial import receptors had been improved at the level of binding affinity.
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Affiliation(s)
- M Angermayr
- Institut für Genetik und Mikrobiologie der Universität München, Maria-Ward-Strasse 1a, D-80638, Munich, Germany
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22
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Carrasco AJ, Dzeja PP, Alekseev AE, Pucar D, Zingman LV, Abraham MR, Hodgson D, Bienengraeber M, Puceat M, Janssen E, Wieringa B, Terzic A. Adenylate kinase phosphotransfer communicates cellular energetic signals to ATP-sensitive potassium channels. Proc Natl Acad Sci U S A 2001; 98:7623-8. [PMID: 11390963 PMCID: PMC34718 DOI: 10.1073/pnas.121038198] [Citation(s) in RCA: 198] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Transduction of energetic signals into membrane electrical events governs vital cellular functions, ranging from hormone secretion and cytoprotection to appetite control and hair growth. Central to the regulation of such diverse cellular processes are the metabolism sensing ATP-sensitive K+ (K(ATP)) channels. However, the mechanism that communicates metabolic signals and integrates cellular energetics with K(ATP) channel-dependent membrane excitability remains elusive. Here, we identify that the response of K(ATP) channels to metabolic challenge is regulated by adenylate kinase phosphotransfer. Adenylate kinase associates with the K(ATP) channel complex, anchoring cellular phosphotransfer networks and facilitating delivery of mitochondrial signals to the membrane environment. Deletion of the adenylate kinase gene compromised nucleotide exchange at the channel site and impeded communication between mitochondria and K(ATP) channels, rendering cellular metabolic sensing defective. Assigning a signal processing role to adenylate kinase identifies a phosphorelay mechanism essential for efficient coupling of cellular energetics with K(ATP) channels and associated functions.
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Affiliation(s)
- A J Carrasco
- Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Mayo Foundation, Guggenheim 7, 200 First Street Southwest, Rochester, MN 55905, USA
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23
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Zikmanis P, Kruce R, Auzina L. Interrelationships between Growth Yield, ATPase and Adenylate Kinase Activities inZymomonas mobilis. ACTA ACUST UNITED AC 2001. [DOI: 10.1002/1521-3846(200105)21:2<171::aid-abio171>3.0.co;2-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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24
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Janssen E, Dzeja PP, Oerlemans F, Simonetti AW, Heerschap A, de Haan A, Rush PS, Terjung RR, Wieringa B, Terzic A. Adenylate kinase 1 gene deletion disrupts muscle energetic economy despite metabolic rearrangement. EMBO J 2000; 19:6371-81. [PMID: 11101510 PMCID: PMC305872 DOI: 10.1093/emboj/19.23.6371] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Efficient cellular energy homeostasis is a critical determinant of muscle performance, providing evolutionary advantages responsible for species survival. Phosphotransfer reactions, which couple ATP production and utilization, are thought to play a central role in this process. Here, we provide evidence that genetic disruption of AK1-catalyzed ss-phosphoryl transfer in mice decreases the potential of myofibers to sustain nucleotide ratios despite up-regulation of high-energy phosphoryl flux through glycolytic, guanylate and creatine kinase phosphotransfer pathways. A maintained contractile performance of AK1-deficient muscles was associated with higher ATP turnover rate and larger amounts of ATP consumed per contraction. Metabolic stress further aggravated the energetic cost in AK1(-/-) muscles. Thus, AK1-catalyzed phosphotransfer is essential in the maintenance of cellular energetic economy, enabling skeletal muscle to perform at the lowest metabolic cost.
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Affiliation(s)
- E Janssen
- Departments of Cell Biology and Diagnostic Radiology, University Medical Center, University of Nijmegen, Institute for Fundamental and Clinical Human Movement Sciences, Vrije University Amsterdam, The Netherlands
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25
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Dzeja PP, Vitkevicius KT, Redfield MM, Burnett JC, Terzic A. Adenylate kinase-catalyzed phosphotransfer in the myocardium : increased contribution in heart failure. Circ Res 1999; 84:1137-43. [PMID: 10347088 DOI: 10.1161/01.res.84.10.1137] [Citation(s) in RCA: 152] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Although the downregulation of creatine kinase activity has been associated with heart failure, creatine kinase-deficient transgenic hearts have a preserved contractile function. This suggests the existence of alternative phosphotransfer pathways in the myocardium, the identity of which is still unknown. In this study, we examined the contribution of adenylate kinase-catalyzed phosphotransfer to myocardial energetics. In the isolated mitochondria/actomyosin system, which possesses endogenous adenylate kinase activity in both compartments, substrates for adenylate kinase promoted the rate and amplitude of actomyosin contraction that was further enhanced by purified adenylate kinase. Inhibition of adenylate kinase activity diminished both actomyosin contraction and mitochondrial respiration, which indicated reduced energy flow between mitochondria and myofibrils. In intact myocardium, the net adenylate kinase-catalyzed phosphotransfer rate was 10% of the total ATP turnover rate as measured by 18O-phosphoryl labeling in conjunction with gas chromatography and mass spectrometry. In pacing-induced failing heart, adenylate kinase-catalyzed phosphotransfer increased by 134% and contributed 21% to the total ATP turnover. Concomitantly, the contribution by creatine kinase dropped from 89% in normal hearts to 40% in failing hearts. These phosphotransfer changes were associated with reduced levels of metabolically active ATP but maintained overall ATP turnover rate. Thus, this study provides evidence that adenylate kinase facilitates the transfer of high-energy phosphoryls and signal communication between mitochondria and actomyosin in cardiac muscle, with an increased contribution to cellular phosphotransfer in heart failure. This phosphotransfer function renders adenylate kinase an important component for optimal myocardial bioenergetics and a compensatory mechanism in response to impaired intracellular energy flux in the failing heart.
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Affiliation(s)
- P P Dzeja
- Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN 55905, USA
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26
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Bandlow W, Strobel G, Schricker R. Influence of N-terminal sequence variation on the sorting of major adenylate kinase to the mitochondrial intermembrane space in yeast. Biochem J 1998; 329 ( Pt 2):359-67. [PMID: 9425120 PMCID: PMC1219052 DOI: 10.1042/bj3290359] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Major adenylate kinase (Aky2p) from yeast has no cleavable presequence and occurs in identical form in the mitochondrial intermembrane space (6-8%) and in the cytoplasm (approx. 90%). To identify the signal(s) on Aky2p that might be required for mitochondrial import, the N-terminal region was examined. The N-terminus of Aky2p can guide at least two cytoplasmic passengers, dihydrofolate reductase from mouse and UMP kinase (Ura6p) from yeast, to the intermembrane space in vivo, showing that the N-terminus harbours import information. In contrast, deletion of the eight N-terminal amino acid residues or the introduction of two compensating frameshifts into this segment does not abolish translocation into the organelle's intermembrane space. Thus internal targeting and sorting information must be present in Aky2p as well. Neither a pronounced amphiphilic alpha-helical moment nor positive charges in the N-terminal region is a necessary prerequisite for Aky2p to reach the intermembrane space. Even a surplus of negative charges in mutant N-termini does not impede basal import into the correct submitochondrial compartment. The potential to form an amphipathic alpha-helical structure of five to eight residues close to the N-terminus significantly improves import efficiency, whereas extension of this amphipathic structure, e.g. by replacing it with the homologous segment of Aky3p, a mitochondrial matrix protein from yeast, leads to misdirection of the chimaera to the matrix compartment. This shows that the topogenic N-terminal signal of Aky3p is dominant over the presumptive internal intermembrane space-targeting signal of Aky2p and argues that the sorting of wild-type Aky2p to the intermembrane space is not due to the presence in the protein of a specific sorting sequence for the intermembrane space, but rather is the consequence of being imported but not being sorted to the inner compartment. Some Aky2 mutant proteins are susceptible to proteolysis in the cytoplasm, indicating incorrect folding. They are nevertheless efficiently rescued by uptake into mitochondria, suggesting a negative correlation between folding velocity (or folding stability) and efficiency of import.
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Affiliation(s)
- W Bandlow
- Institut für Genetik und Mikrobiologie, Universität München, Maria-Ward-Strasse 1a, D-80638 München, Federal Republic of Germany
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27
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Fukami-Kobayashi K, Nosaka M, Nakazawa A, Go M. Ancient divergence of long and short isoforms of adenylate kinase: molecular evolution of the nucleoside monophosphate kinase family. FEBS Lett 1996; 385:214-20. [PMID: 8647254 DOI: 10.1016/0014-5793(96)00367-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Adenylate kinases (AK) from vertebrates are separated into three isoforms, AK1, AK2 and AK3, based on structure, subcellular localization and substrate specificity. AK1 is the short type with the amino acid sequence being 27 residues shorter than sequences of the long types, AK2 and AK3. A phylogenetic tree prepared for the AK isozymes and other members of the nucleoside monophosphate (NMP) kinase family shows that the divergence of long and short types occurred first and then differentiation in subcellular localization or substrate specificity took place. The first step involved a drastic change in the three-dimensional structure of the LID domain. The second step was caused mainly by smaller changes in amino acid sequences.
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28
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Klier H, Magdolen V, Schricker R, Strobel G, Lottspeich F, Bandlow W. Cytoplasmic and mitochondrial forms of yeast adenylate kinase 2 are N-acetylated. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1280:251-6. [PMID: 8639701 DOI: 10.1016/0005-2736(95)00304-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Yeast major adenylate kinase (Aky2p), encoded by a single gene, occurs in two subcellular compartments, mitochondria and cytoplasm. Only 6-8% of the protein which has no cleavable presequence is imported into the organelle (Bandlow et al. (1988) Eur. J. Biochem. 178, 451-457). In the wild type two AKY2-derived signals (a major and a minor one) were detected by a monospecific antibody after two-dimensional gel electrophoresis and Western blotting. The signals reflected identical electrophoretic mobilities and were absent from an AKY2-disrupted strain suggesting that they were due to differently modified forms of Aky2p. Two similar signals were found in a mutant defective in protein N-acetylation, however, the pI values of both spots were shifted towards alkaline pH by one charge. This indicated that both forms of Aky2p were N-acetylated in the wild type and that their charge difference was not caused by incomplete N-acetylation. This observation furthermore suggested that, in the wild type, two different modifications exist one of which is N-acetylation. The second modification remains unidentified. We analysed the influence of protein N-acetylation on mitochondrial import. Both versions of Aky2p occurred in the cytoplasm and in mitochondria. Their proportion was unchanged in the N-acetylation mutant showing that neither modification affected the efficiency of import of adenylate kinase into mitochondria. It is discussed that N-acetylation occurs during or immediately after translation in the cytoplasm so that import of adenylate kinase may ensue co-translationally.
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Affiliation(s)
- H Klier
- Max-Planck-Institut für Biochemie, Martinsried, Germany
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29
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Schricker R, Magdolen V, Strobel G, Bogengruber E, Breitenbach M, Bandlow W. Strain-dependent occurrence of functional GTP:AMP phosphotransferase (AK3) in Saccharomyces cerevisiae. J Biol Chem 1995; 270:31103-10. [PMID: 8537371 DOI: 10.1074/jbc.270.52.31103] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The gene for yeast GTP:AMP phosphotransferase (PAK3) was found to encode a nonfunctional protein in 10 laboratory strains and one brewers' strain. The protein product showed high similarity to vertebrate AK3 and was located exclusively in the mitochondrial matrix. The deduced amino acid sequence revealed a protein that was shorter at the carboxyl terminus than all other known adenylate kinases. Introduction of a +1 frameshift into the 3'-terminal region of the gene extended homology of the deduced amino acid sequence to other members of the adenylate kinase family including vertebrate AK3. Frameshift mutations obtained after in vitro and in vivo mutagenesis were capable of complementing the adk1 temperature-conditional deficiency in Escherichia coli, indicating that the frameshift led to the expression of a protein that could phosphorylate AMP. Some yeasts, however, including strain D273-10B, two wine yeasts, and two more distantly related yeast genera, harbored an active allele, named AKY3, which contained a +1 frameshift close to the carboxyl terminus as compared with the laboratory strains. The encoded protein exhibited GTP:AMP and ITP:AMP phosphotransferase activities but did not accept ATP as phosphate donor. Although single copy in the haploid genome, disruption of the AKY3 allele displayed no phenotype, excluding the possibility that laboratory and brewers' strains had collected second site suppressors. It must be concluded that yeast mitochondria can completely dispense with GTP:AMP phosphotransferase activity.
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Affiliation(s)
- R Schricker
- Institut für Genetik und Mikrobiologie, Universität München, Germany
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Nyame K, Do-Thi CD, Opperdoes FR, Michels PA. Subcellular distribution and characterization of glucosephosphate isomerase in Leishmania mexicana mexicana. Mol Biochem Parasitol 1994; 67:269-79. [PMID: 7870131 DOI: 10.1016/0166-6851(94)00139-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The glycolytic enzyme glucosephosphate isomerase (PGI) is present in two different cell compartments of Leishmania mexicana promastigotes; more than 90% of the activity was detected in the cytosol, the remainder in glycosomes. This subcellular distribution contrasts with that in Trypanosoma brucei, in which the enzyme activity has been mainly located in the glycosomes. PGI was partially purified from L. mexicana cell extracts. Throughout the purification procedure only one single PGI activity could be detected. The partially purified protein had the same subunit molecular mass (65 kDa) as the previously characterized glycosomal protein of T. brucei. Both proteins were also very similar with respect to their kinetic and antigenic properties. Using the T. brucei glycosomal PGI gene as a hybridization probe, we cloned the corresponding gene of L. mexicana. Only a single PGI locus could be detected in the L. mexicana genome. Characterization of the cloned gene showed that it codes for a polypeptide of 604 amino acids, with a molecular mass of 67,113. The sequences of the Leishmania and Trypanosoma polypeptides are 69% identical. They differ in calculated net charge (-8 versus -2, respectively) and isoelectric point (6.65 versus 7.35). Our data strongly suggest that the PGI activity in the two cell compartments of L. mexicana and T. brucei is not attributable to different isoenzymes. We discuss the possible metabolic function of the highly different enzyme distribution in the two organisms, and the molecular mechanism that could be responsible for it.
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Affiliation(s)
- K Nyame
- International Institute of Cellular and Molecular Pathology, Research Unit for Tropical Diseases, Brussels, Belgium
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31
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Länge S, Rozario C, Müller M. Primary structure of the hydrogenosomal adenylate kinase of Trichomonas vaginalis and its phylogenetic relationships. Mol Biochem Parasitol 1994; 66:297-308. [PMID: 7808479 DOI: 10.1016/0166-6851(94)90156-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Hydrogenosomal adenylate kinase of the amitochondriate protist, Trichomonas vaginalis, has been purified and the sequence of its 39 amino-terminal residues established. Based on this sequence and a conserved internal region of the enzyme, a probe was obtained by DNA polymerase chain reaction and used to isolate a genomic DNA clone containing the gene of this enzyme. This gene exists probably as a single copy in T. vaginalis and is not interrupted by introns. The open reading frame obtained codes for a large type adenylate kinase with a mature molecular mass of 24.5 kDa. The T. vaginalis enzyme is homologous with adenylate kinases of other eukaryotes and eubacteria. Strongly conserved parts and residues of the molecule are conserved also in this enzyme. Phylogenetic trees obtained with various methods placed the T. vaginalis adenylate kinase close to the point where the different subfamilies of this enzyme branch from each other, indicating that the T. vaginalis enzyme has no close relationship to any of these subfamilies and that it separated early from other adenylate kinases. The conceptual translation predicts the existence of an amino-terminal nonapeptide absent from the protein purified from hydrogenosomes, similar to the processed amino-terminal extensions of other hydrogenosomal proteins. These extensions have been considered as putative targeting and import signals.
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Affiliation(s)
- S Länge
- Rockefeller University, New York, NY 10021
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32
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Konrad M. Identification and characterization of a yeast gene encoding an adenylate kinase homolog. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1172:12-6. [PMID: 8439550 DOI: 10.1016/0167-4781(93)90262-c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Screening for genes homologous to adenylate kinase in the yeast Saccharomyces cerevisiae resulted in the isolation of a homolog of the previously characterized ADK1. The derived protein sequence is most closely related to mammalian GTP:AMP phosphotransferase (adenylate kinase isozyme 3; AK3); this novel gene is therefore named ADK3. Its deletion from the yeast genome does not lead to an observable change in cellular phenotype. A strain defective for both ADK1 and ADK3 is viable. When introduced on a multicopy plasmid into an ADK1-deficient yeast strain, which shows a reduced proliferation rate, ADK3 did not rescue this growth defect. The protein was also highly overexpressed in E. coli cells. However, no change in enzymatic activity was detected in cellular extracts of yeast or bacteria.
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Affiliation(s)
- M Konrad
- Department of Molecular Genetics, Max-Planck-Institute for Biophysical Chemistry, Götting, Germany
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Schricker R, Magdolen V, Kaniak A, Wolf K, Bandlow W. The adenylate kinase family in yeast: identification of URA6 as a multicopy suppressor of deficiency in major AMP kinase. Gene 1992; 122:111-8. [PMID: 1333436 DOI: 10.1016/0378-1119(92)90038-q] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The gene URA6 encoding uridylate kinase (UK) from Saccharomyces cerevisiae was isolated as a multicopy suppressor of the respiratory-deficient phenotype of an S. cerevisiae mutant defective in the gene AKY2 encoding AMP kinase (AK). The URA6 gene also restored temperature resistance to two different temperature-sensitive mutations in the gene encoding Escherichia coli AK. By contrast, the gene encoding UK of Dictyostelium discoideum on a multicopy yeast shuttle plasmid, expressed under control of the constitutive yeast AKY2 promoter, failed to complement the deficiency in yeast, although such transformants expressed high UK activity. We show that yeast UK exerts significant AK activity which is responsible for the complementation and is absent in the analogous enzyme from D. discoideum. Since UK also significantly phosphorylates CMP (but not GMP), it must be considered an unspecific short-form nucleoside monophosphate kinase. Wild-type mitochondria lack UK activity, but import AKY2. Since multicopy transformation with URA6 heals the Pet- phenotype of AKY2 disruption mutants, the presence of AKY2 in the mitochondrial intermembrane space is not required to maintain respiratory competence. However, furnishing UK with the bipartite intermembrane space-targeting presequence of cytochrome c1 improves the growth rates of AKY2 mutants with nonfermentable substrates, suggesting that AK activity in mitochondria is helpful, though not essential for oxidative growth.
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Affiliation(s)
- R Schricker
- Institut für Genetik und Mikrobiologie, Universität München, Germany
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34
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Schricker R, Magdolen V, Bandlow W. A new member of the adenylate kinase family in yeast: PAK3 is highly homologous to mammalian AK3 and is targeted to mitochondria. MOLECULAR & GENERAL GENETICS : MGG 1992; 233:363-71. [PMID: 1620094 DOI: 10.1007/bf00265432] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Making use of the polymerase chain reaction primed by oligonucleotides corresponding to regions conserved between members of the nucleoside monophosphate kinase family, we have isolated the yeast gene PAK3. Pak3p belongs to the subgroup of long-form adenylate kinase isozymes (deduced molecular mass 25.3 kDa) and exhibits highest sequence similarity to bovine AK3 rather than to the yeast isozyme, Aky2p. The gene is shown to be non-essential because haploid disruption mutants are viable, both in the presence and absence of a functional AKY2 allele. It maps on chromosome V upstream of RAD3. Its expression level is low when cells are grown on glucose or other fermentable carbon sources and about threefold higher on glycerol, but can be significantly induced by ethanol. A PAK3/mouse dihydrofolate reductase fusion construct expressed in yeast is targeted to mitochondria. Transformation with PAK3 on a multicopy plasmid complements neither adenylate kinase deficiency in an aky2-disrupted yeast strain nor in Escherichia coli cells conditionally defective in adenylate kinase.
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Affiliation(s)
- R Schricker
- Institut für Pathologie, Universität Ulm, FRG
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35
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Cooper AJ, Friedberg EC. A putative second adenylate kinase-encoding gene from the yeast Saccharomyces cerevisiae. Gene 1992; 114:145-8. [PMID: 1587477 DOI: 10.1016/0378-1119(92)90721-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Sequencing of the region upstream from the yeast RAD3 gene has revealed an open reading frame (ORF) of 225 amino acids (aa) that could encode a 25.3-kDa polypeptide. The predicted aa sequence of this ORF is homologous with that of several eukaryotic adenylate kinase (Adk)-encoding genes, including the yeast gene, ADK1. These findings suggest that the yeast Saccharomyces cerevisiae has a second Adk-encoding gene, tentatively designated as ADK2.
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Affiliation(s)
- A J Cooper
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235
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36
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Oechsner U, Hermann H, Zollner A, Haid A, Bandlow W. Expression of yeast cytochrome c1 is controlled at the transcriptional level by glucose, oxygen and haem. MOLECULAR & GENERAL GENETICS : MGG 1992; 232:447-59. [PMID: 1316998 DOI: 10.1007/bf00266250] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The nuclear gene for cytochrome c1 in Saccharomyces cerevisiae (CYT1) was localized on chromosome XV. Its upstream region was identified by functional complementation. Fusion to the lacZ reporter gene on a CEN plasmid allowed study of the effect of carbon sources and of specific deletion mutations on expression of the gene in yeast transformants. Detailed promoter analysis combined with expression studies in recipient strains defective in regulatory genes identified cis-acting sites and transcription factors involved in the regulated expression of the cytochrome c1 gene. These analyses showed that, in the presence of glucose, transcription of CYT1 is positively controlled by oxygen, presumably through the haem signal, and mediated by the HAP1-encoded transactivator. It is additionally regulated by the HAP2/3/4 complex which mediates gene activation mainly under glucose-free conditions. Basal transcription is, in part, effected by CPF1, a centromere and promoter-binding factor.
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MESH Headings
- Base Sequence
- Binding Sites
- Chromosome Deletion
- Chromosome Mapping
- Chromosomes, Fungal
- Cloning, Molecular
- Cytochromes c1/genetics
- Cytochromes c1/metabolism
- DNA, Fungal/genetics
- DNA, Fungal/isolation & purification
- Gene Expression Regulation, Fungal/drug effects
- Genes, Fungal
- Genes, Regulator
- Glucose/pharmacology
- Heme/pharmacology
- Molecular Sequence Data
- Oxygen/pharmacology
- Promoter Regions, Genetic
- Recombinant Fusion Proteins/metabolism
- Regulatory Sequences, Nucleic Acid
- Saccharomyces cerevisiae/drug effects
- Saccharomyces cerevisiae/genetics
- Saccharomyces cerevisiae/metabolism
- Sequence Homology, Nucleic Acid
- Transcription Factors/metabolism
- Transcription, Genetic/drug effects
- Transcriptional Activation
- beta-Galactosidase/genetics
- beta-Galactosidase/metabolism
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Affiliation(s)
- U Oechsner
- Institut für Genetik und Mikrobiologie, München, FRG
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Magdolen V, Schricker R, Strobel G, Germaier H, Bandlow W. In vivo import of yeast adenylate kinase into mitochondria affected by site-directed mutagenesis. FEBS Lett 1992; 299:267-72. [PMID: 1544504 DOI: 10.1016/0014-5793(92)80129-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Site-directed mutagenesis and deletions were used to study mitochondrial import of a major yeast adenylate kinase, Aky2p. This enzyme lacks a cleavable presequence and occurs in active and apparently unprocessed form both in mitochondria and cytoplasm. Mutations were applied to regions known to be surface-exposed and to diverge between short and long isoforms. In vertebrates, short adenylate kinase isozymes occur exclusively in the cytoplasm, whereas long versions of the enzyme have mitochondrial locations. Mutations in the extra loop of the yeast (long-form) enzyme did not affect mitochondrial import of the protein, whereas variants altered in the central, N- or C-terminal parts frequently displayed increased or, in the case of a deletion of the 8 N-terminal triplets, decreased import efficiencies. Although the N-terminus is important for targeting adenylate kinase to mitochondria, other parameters like internal sequence determinants and folding velocity of the nascent protein may also play a role.
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Affiliation(s)
- V Magdolen
- Institut für Genetik und Mikrobiologie, Munich, Germany
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