1
|
Pevala V, Truban D, Bauer JA, Košťan J, Kunová N, Bellová J, Brandstetter M, Marini V, Krejčí L, Tomáška Ľ, Nosek J, Kutejová E. The structure and DNA-binding properties of Mgm101 from a yeast with a linear mitochondrial genome. Nucleic Acids Res 2016; 44:2227-39. [PMID: 26743001 PMCID: PMC4797282 DOI: 10.1093/nar/gkv1529] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 12/22/2015] [Indexed: 11/14/2022] Open
Abstract
To study the mechanisms involved in the maintenance of a linear mitochondrial genome we investigated the biochemical properties of the recombination protein Mgm101 from Candida parapsilosis. We show that CpMgm101 complements defects associated with the Saccharomyces cerevisiae mgm101-1(ts) mutation and that it is present in both the nucleus and mitochondrial nucleoids of C. parapsilosis. Unlike its S. cerevisiae counterpart, CpMgm101 is associated with the entire nucleoid population and is able to bind to a broad range of DNA substrates in a non-sequence specific manner. CpMgm101 is also able to catalyze strand annealing and D-loop formation. CpMgm101 forms a roughly C-shaped trimer in solution according to SAXS. Electron microscopy of a complex of CpMgm101 with a model mitochondrial telomere revealed homogeneous, ring-shaped structures at the telomeric single-stranded overhangs. The DNA-binding properties of CpMgm101, together with its DNA recombination properties, suggest that it can play a number of possible roles in the replication of the mitochondrial genome and the maintenance of its telomeres.
Collapse
Affiliation(s)
- Vladimír Pevala
- Department of Biochemistry and Structural Biology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Dominika Truban
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-1, Ilkovičova 6, 842 15 Bratislava, Slovakia
| | - Jacob A Bauer
- Department of Biochemistry and Structural Biology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Július Košťan
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, Dr. Bohr-Gasse 9 (VBC 5), 1030 Vienna, Austria
| | - Nina Kunová
- Department of Biochemistry and Structural Biology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Jana Bellová
- Department of Biochemistry and Structural Biology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Marlene Brandstetter
- Electron Microscopy Facility of the Campus Science Support Facilities GmbH, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Victoria Marini
- Department of Biology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic National Centre for Biomolecular Research, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Lumír Krejčí
- Department of Biology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic National Centre for Biomolecular Research, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Ľubomír Tomáška
- Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynská dolina B-1, Ilkovičova 6, 842 15 Bratislava, Slovakia
| | - Jozef Nosek
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-1, Ilkovičova 6, 842 15 Bratislava, Slovakia
| | - Eva Kutejová
- Department of Biochemistry and Structural Biology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia Institute of Microbiology of the CAS, v. v. i., 142 20 Prague, Czech Republic
| |
Collapse
|
2
|
Wagatsuma A, Kotake N, Mabuchi K, Yamada S. Expression of nuclear-encoded genes involved in mitochondrial biogenesis and dynamics in experimentally denervated muscle. J Physiol Biochem 2011; 67:359-70. [PMID: 21394548 DOI: 10.1007/s13105-011-0083-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 02/22/2011] [Indexed: 12/28/2022]
Abstract
The abundance, morphology, and functional properties of mitochondria become altered in response to denervation. To gain insight into the regulation of this process, mitochondrial enzyme activities and gene expression involved in mitochondrial biogenesis and dynamics in mouse gastrocnemius muscle was investigated. Sciatic nerve transactions were performed on mice, and then gastrocnemius muscles were isolated at days 5 and 30 after surgery. Muscle weight was decreased significantly by 15% and 62% at days 5 and 30 after surgery, respectively. The activity of citrate synthase, a marker of oxidative enzyme, was reduced significantly by 31% and 53% at days 5 and 30, respectively. Enzyme histochemical analysis revealed that subsarcolemmal mitochondria were largely lost than intermyofibrillar mitochondria at day 5, and this trend was further progressed at day 30 after surgery. Expression levels of peroxisome proliferator-activated receptor, γ coactivator 1 (PGC-1)α, estrogen-related receptor α (ERRα), and mitofusin 2 were down-regulated throughout the experimental period, whereas those of PGC-1β, PRC, nuclear respiratory factor (NRF)-1, NRF-2, TFAM, and Lon protease were down-regulated at day 30 after surgery. These results suggest that PGC-1α, ERRα, and mitofusin 2 may be important factors in the process of denervation-induced mitochondrial adaptation. In addition, other PGC-1 family of transcriptional coactivators and DNA binding transcription factors may also contribute to mitochondrial adaptation after early response to denervation.
Collapse
Affiliation(s)
- Akira Wagatsuma
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
| | | | | | | |
Collapse
|
3
|
Shapovalov Y, Hoffman D, Zuch D, de Mesy Bentley KL, Eliseev RA. Mitochondrial dysfunction in cancer cells due to aberrant mitochondrial replication. J Biol Chem 2011; 286:22331-8. [PMID: 21536680 DOI: 10.1074/jbc.m111.250092] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Warburg effect is a hallmark of cancer manifested by continuous prevalence of glycolysis and dysregulation of oxidative metabolism. Glycolysis provides survival advantage to cancer cells. To investigate molecular mechanisms underlying the Warburg effect, we first compared oxygen consumption among hFOB osteoblasts, benign osteosarcoma cells, Saos2, and aggressive osteosarcoma cells, 143B. We demonstrate that, as both proliferation and invasiveness increase in osteosarcoma, cells utilize significantly less oxygen. We proceeded to evaluate mitochondrial morphology and function. Electron microscopy showed that in 143B cells, mitochondria are enlarged and increase in number. Quantitative PCR revealed an increase in mtDNA in 143B cells when compared with hFOB and Saos2 cells. Gene expression studies showed that mitochondrial single-strand DNA-binding protein (mtSSB), a key catalyst of mitochondrial replication, was significantly up-regulated in 143B cells. In addition, increased levels of the mitochondrial respiratory complexes were accompanied by significant reduction of their activities. These changes indicate hyperactive mitochondrial replication in 143B cells. Forced overexpression of mtSSB in Saos2 cells caused an increase in mtDNA and a decrease in oxygen consumption. In contrast, knockdown of mtSSB in 143B cells was accompanied by a decrease in mtDNA, increase in oxygen consumption, and retardation of cell growth in vitro and in vivo. In summary, we have found that mitochondrial dysfunction in cancer cells correlates with abnormally increased mitochondrial replication, which according to our gain- and loss-of-function experiments, may be due to overexpression of mtSSB. Our study provides insight into mechanisms of mitochondrial dysfunction in cancer and may offer potential therapeutic targets.
Collapse
Affiliation(s)
- Yuriy Shapovalov
- The Center for Musculoskeletal Research, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA
| | | | | | | | | |
Collapse
|
4
|
Wagatsuma A, Kotake N, Kawachi T, Shiozuka M, Yamada S, Matsuda R. Mitochondrial adaptations in skeletal muscle to hindlimb unloading. Mol Cell Biochem 2011; 350:1-11. [PMID: 21165677 DOI: 10.1007/s11010-010-0677-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 12/02/2010] [Indexed: 12/20/2022]
Abstract
To gain insight into the regulation of mitochondrial adaptations to hindlimb unloading (HU), the activity of mitochondrial enzymes and the expression of nuclear-encoded genes which control mitochondrial properties in mouse gastrocnemius muscle were investigated. Biochemical and enzyme histochemical analysis showed that subsarcolemmal mitochondria were lost largely than intermyofibrillar mitochondria after HU. Gene expression analysis revealed disturbed or diminished gene expression patterns. The three main results of this analysis are as follows. First, in contrast to peroxisome proliferator-activated receptor γ coactivator 1 β (PGC-1β) and PGC-1-related coactivator, which were down-regulated by HU, PGC-1α was up-regulated concomitant with decreased expression of its DNA binding transcription factors, PPARα, and estrogen-related receptor α (ERRα). Moreover, there was no alteration in expression of nuclear respiratory factor 1, but its downstream target gene, mitochondrial transcription factor A, was down-regulated. Second, both mitofusin 2 and fission 1, which control mitochondrial morphology, were down-regulated. Third, ATP-dependent Lon protease, which participates in mitochondrial-protein degradation, was also down-regulated. These findings suggest that HU may induce uncoordinated expression of PGC-1 family coactivators and DNA binding transcription factors, resulting in reducing ability of mitochondrial biogenesis. Furthermore, down-regulation of mitochondrial morphology-related genes associated with HU may be also involved in alterations in intracellular mitochondrial distribution.
Collapse
MESH Headings
- Adaptation, Physiological/genetics
- Adaptation, Physiological/physiology
- Animals
- Citrate (si)-Synthase/genetics
- Citrate (si)-Synthase/metabolism
- Female
- Gene Expression Regulation
- Gene Expression Regulation, Enzymologic
- Hindlimb Suspension/physiology
- Mice
- Mitochondria, Muscle/genetics
- Mitochondria, Muscle/metabolism
- Mitochondria, Muscle/physiology
- Muscle Proteins/genetics
- Muscle Proteins/metabolism
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/physiology
- PPAR gamma/genetics
- PPAR gamma/metabolism
- Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- SKP Cullin F-Box Protein Ligases/genetics
- SKP Cullin F-Box Protein Ligases/metabolism
- Succinate Dehydrogenase/genetics
- Succinate Dehydrogenase/metabolism
- Trans-Activators/genetics
- Trans-Activators/metabolism
- Transcription Factors
- ERRalpha Estrogen-Related Receptor
Collapse
Affiliation(s)
- Akira Wagatsuma
- Department of Life Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan.
| | | | | | | | | | | |
Collapse
|
5
|
Muscle regeneration occurs to coincide with mitochondrial biogenesis. Mol Cell Biochem 2010; 349:139-47. [DOI: 10.1007/s11010-010-0668-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Accepted: 11/15/2010] [Indexed: 01/04/2023]
|
6
|
Oliveira MT, Kaguni LS. Functional roles of the N- and C-terminal regions of the human mitochondrial single-stranded DNA-binding protein. PLoS One 2010; 5:e15379. [PMID: 21060847 PMCID: PMC2965674 DOI: 10.1371/journal.pone.0015379] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Accepted: 08/31/2010] [Indexed: 12/31/2022] Open
Abstract
Biochemical studies of the mitochondrial DNA (mtDNA) replisome demonstrate that the mtDNA polymerase and the mtDNA helicase are stimulated by the mitochondrial single-stranded DNA-binding protein (mtSSB). Unlike Escherichia coli SSB, bacteriophage T7 gp2.5 and bacteriophage T4 gp32, mtSSBs lack a long, negatively charged C-terminal tail. Furthermore, additional residues at the N-terminus (notwithstanding the mitochondrial presequence) are present in the sequence of species across the animal kingdom. We sought to analyze the functional importance of the N- and C-terminal regions of the human mtSSB in the context of mtDNA replication. We produced the mature wild-type human mtSSB and three terminal deletion variants, and examined their physical and biochemical properties. We demonstrate that the recombinant proteins adopt a tetrameric form, and bind single-stranded DNA with similar affinities. They also stimulate similarly the DNA unwinding activity of the human mtDNA helicase (up to 8-fold). Notably, we find that unlike the high level of stimulation that we observed previously in the Drosophila system, stimulation of DNA synthesis catalyzed by human mtDNA polymerase is only moderate, and occurs over a narrow range of salt concentrations. Interestingly, each of the deletion variants of human mtSSB stimulates DNA synthesis at a higher level than the wild-type protein, indicating that the termini modulate negatively functional interactions with the mitochondrial replicase. We discuss our findings in the context of species-specific components of the mtDNA replisome, and in comparison with various prokaryotic DNA replication machineries.
Collapse
Affiliation(s)
- Marcos T. Oliveira
- Department of Biochemistry and Molecular Biology, Center for Mitochondrial Science and Medicine, and Graduate Program in Genetics, Michigan State University, East Lansing, Michigan, United States of America
| | - Laurie S. Kaguni
- Department of Biochemistry and Molecular Biology, Center for Mitochondrial Science and Medicine, and Graduate Program in Genetics, Michigan State University, East Lansing, Michigan, United States of America
- * E-mail:
| |
Collapse
|
7
|
Tomaska L, Nosek J, Kramara J, Griffith JD. Telomeric circles: universal players in telomere maintenance? Nat Struct Mol Biol 2009; 16:1010-5. [PMID: 19809492 PMCID: PMC4041010 DOI: 10.1038/nsmb.1660] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
To maintain linear DNA genomes, organisms have evolved numerous means of solving problems associated with DNA ends (telomeres), including telomere-associated retrotransposons, palindromes, hairpins, covalently bound proteins and the addition of arrays of simple DNA repeats. Telomeric arrays can be maintained through various mechanisms such as telomerase activity or recombination. The recombination-dependent maintenance pathways may include telomeric loops (t-loops) and telomeric circles (t-circles). The potential involvement of t-circles in telomere maintenance was first proposed for linear mitochondrial genomes. The occurrence of t-circles in a wide range of organisms, spanning yeasts, plants and animals, suggests the involvement of t-circles in many phenomena including the alternative-lengthening of telomeres (ALT) pathway and telomere rapid deletion (TRD). In this Perspective, we summarize these findings and discuss how t-circles may be related to t-loops and how t-circles may have initiated the evolution of telomeres.
Collapse
Affiliation(s)
- Lubomir Tomaska
- Department of Genetics, Comenius University in Bratislava, Faculty of Natural Sciences, Bratislava, Slovakia.
| | | | | | | |
Collapse
|
8
|
Radulovic M, Crane E, Crawford M, Godovac-Zimmermann J, Yu VPCC. CKS proteins protect mitochondrial genome integrity by interacting with mitochondrial single-stranded DNA-binding protein. Mol Cell Proteomics 2009; 9:145-52. [PMID: 19786724 DOI: 10.1074/mcp.m900078-mcp200] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cyclin-dependent kinase subunit (CKS) proteins interact with cyclin-dependent kinases (CDKs) with high affinity. Mammalian CKS1 and CKS2 bind CDK1 and CDK2 and partake in the control of cell cycle progression. We identified CKS-interacting proteins by affinity purification followed by mass spectrometry in the human lymphocytic cell line Ramos. Apart from known interactors, such as CDKs, we identified a novel CDK-dependent interaction between CKS proteins and the mitochondrial single-stranded DNA-binding protein (mtSSB). mtSSB bound both CKS1 and CKS2 and underwent CDK-dependent phosphorylation. mtSSB is known to participate in replication of mitochondrial DNA. We demonstrated that mitochondrial morphology and DNA integrity were compromised in cells depleted of both CKS proteins or that had inhibited CDK activity. These features are consistent with the hypothesis of CKS-dependent regulation of mtSSB function and support a direct role of cell cycle proteins in controlling mitochondrial DNA replication.
Collapse
Affiliation(s)
- Marko Radulovic
- Eukaryotic Chromatin Dynamics Group, Medical Research Council Clinical Sciences Centre, Imperial College Hammersmith Campus, Du Cane Road, London, UK
| | | | | | | | | |
Collapse
|
9
|
Witte G, Urbanke C, Curth U. DNA polymerase III chi subunit ties single-stranded DNA binding protein to the bacterial replication machinery. Nucleic Acids Res 2003; 31:4434-40. [PMID: 12888503 PMCID: PMC169888 DOI: 10.1093/nar/gkg498] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2003] [Revised: 05/28/2003] [Accepted: 06/05/2003] [Indexed: 11/13/2022] Open
Abstract
Single-stranded DNA binding (SSB) protein binds to single-stranded DNA (ssDNA) at the lagging strand of the replication fork in Escherichia coli cells. This protein is essential for the survival of the E.coli cell, presumably because it shields the ssDNA and holds it in a suitable conformation for replication by DNA polymerase III. In this study we undertook a biophysical analysis of the interaction between the SSB protein of E.coli and the chi subunit of DNA polymerase III. Using analytical ultracentrifugation we show that at low salt concentrations there is an increase in the stability in the physical interaction between chi and an EcoSSB/ssDNA complex when compared to that of chi to EcoSSB alone. This increase in stability disappeared in high salt conditions. The sedimentation of an EcoSSB protein lacking its C-terminal 26 amino acids remains unchanged in the presence of chi, showing that chi interacts specifically with the C-terminus of EcoSSB. In DNA melting experiments we demonstrate that chi specifically enhances the ssDNA stabilization by EcoSSB. Thus, the binding of EcoSSB to chi at the replication fork prevents premature dissociation of EcoSSB from the lagging strand and thereby enhances the processivity of DNA polymerase III.
Collapse
Affiliation(s)
- Gregor Witte
- Medizinische Hochschule, Zentrale Einrichtung für Biophysikalisch-Biochemische Verfahren, Carl Neuberg Strasse 1, D-30625 Hannover, Germany
| | | | | |
Collapse
|