Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

A nuclear role for the respiratory enzyme CLK-1 in regulating mitochondrial stress responses and longevity

Nature Cell Biology volume 17, pages 782–792 (2015)Cite this article

Subjects

Abstract

The coordinated regulation of mitochondrial and nuclear activities is essential for cellular respiration and its disruption leads to mitochondrial dysfunction, a hallmark of ageing. Mitochondria communicate with nuclei through retrograde signalling pathways that modulate nuclear gene expression to maintain mitochondrial homeostasis. The monooxygenase CLK-1 (human homologue COQ7) was previously reported to be mitochondrial, with a role in respiration and longevity. We have uncovered a distinct nuclear form of CLK-1 that independently regulates lifespan. Nuclear CLK-1 mediates a retrograde signalling pathway that is conserved from Caenorhabditis elegans to humans and is responsive to mitochondrial reactive oxygen species, thus acting as a barometer of oxidative metabolism. We show that, through modulation of gene expression, the pathway regulates both mitochondrial reactive oxygen species metabolism and the mitochondrial unfolded protein response. Our results demonstrate that a respiratory enzyme acts in the nucleus to control mitochondrial stress responses and longevity.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: CLK-1 and its human homologue COQ7 localize to mitochondria and nuclei.
Figure 2: Nuclear COQ7 functions independently of the mitochondrial form.
Figure 3: A truncated form of C. elegans CLK-1 with impaired mitochondrial targeting is predominantly nuclear and does not rescue ubiquinone biosynthesis.
Figure 4: Nuclear CLK-1 and COQ7 regulate ROS metabolism.
Figure 5: Mitochondrial and nuclear CLK-1 independently contribute to longevity.
Figure 6: Nuclear CLK-1 and COQ7 suppress the expression of a subset of UPRmt genes.
Figure 7: COQ7 associates with chromatin.
Figure 8: Model for the regulation of ROS metabolism, the UPRmt and lifespan by nuclear CLK-1.

Similar content being viewed by others

References

  1. Tait, S. W. & Green, D. R. Mitochondria and cell signalling. J. Cell Sci. 125, 807–815 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  2. Chandel, N. S. Mitochondria as signaling organelles. BMC Biol. 12, 34 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  3. Sena, L. A. & Chandel, N. S. Physiological roles of mitochondrial reactive oxygen species. Mol. Cell 48, 158–167 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  4. Whelan, S. P. & Zuckerbraun, B. S. Mitochondrial signaling: forwards, backwards, and in between. Oxid. Med. Cell. Longev. 2013, 351613 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Kotiadis, V. N., Duchen, M. R. & Osellame, L. D. Mitochondrial quality control and communications with the nucleus are important in maintaining mitochondrial function and cell health. Biochim. Biophys. Acta 1840, 1254–1265 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  6. Yee, C., Yang, W. & Hekimi, S. The intrinsic apoptosis pathway mediates the pro-longevity response to mitochondrial ROS in C. elegans. Cell 157, 897–909 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Lopez-Otin, C., Blasco, M. A., Partridge, L., Serrano, M. & Kroemer, G. The hallmarks of aging. Cell 153, 1194–1217 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Riera, C. E. & Dillin, A. Tipping the metabolic scales towards increased longevity in mammals. Nat. Cell Biol. 17, 196–203 (2015).

    Article  CAS  PubMed  Google Scholar 

  9. Yun, J. & Finkel, T. Mitohormesis. Cell Metab. 19, 757–766 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Schulz, T. J. et al. Glucose restriction extends Caenorhabditis elegans life span by inducing mitochondrial respiration and increasing oxidative stress. Cell Metab. 6, 280–293 (2007).

    Article  CAS  PubMed  Google Scholar 

  11. Nargund, A. M., Pellegrino, M. W., Fiorese, C. J., Baker, B. M. & Haynes, C. M. Mitochondrial import efficiency of ATFS-1 regulates mitochondrial UPR activation. Science 337, 587–590 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Houtkooper, R. H. et al. Mitonuclear protein imbalance as a conserved longevity mechanism. Nature 497, 451–457 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. Jensen, M. B. & Jasper, H. Mitochondrial proteostasis in the control of aging and longevity. Cell Metab. 20, 214–225 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Dillin, A. et al. Rates of behavior and aging specified by mitochondrial function during development. Science 298, 2398–2401 (2002).

    Article  CAS  PubMed  Google Scholar 

  15. Marbois, B. N. & Clarke, C. F. The COQ7 gene encodes a protein in Saccharomyces cerevisiae necessary for ubiquinone biosynthesis. J. Biol. Chem. 271, 2995–3004 (1996).

    Article  CAS  PubMed  Google Scholar 

  16. Jonassen, T. et al. Yeast Clk-1 homologue (Coq7/Cat5) is a mitochondrial protein in coenzyme Q synthesis. J. Biol. Chem. 273, 3351–3357 (1998).

    Article  CAS  PubMed  Google Scholar 

  17. Wong, A., Boutis, P. & Hekimi, S. Mutations in the clk-1 gene of Caenorhabditis elegans affect developmental and behavioral timing. Genetics 139, 1247–1259 (1995).

    CAS  PubMed  PubMed Central  Google Scholar 

  18. Ewbank, J. J. et al. Structural and functional conservation of the Caenorhabditis elegans timing gene clk-1. Science 275, 980–983 (1997).

    Article  CAS  PubMed  Google Scholar 

  19. Jonassen, T., Larsen, P. L. & Clarke, C. F. A dietary source of coenzyme Q is essential for growth of long-lived Caenorhabditis elegans clk-1 mutants. Proc. Natl Acad. Sci. USA 98, 421–426 (2001).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Levavasseur, F. et al. Ubiquinone is necessary for mouse embryonic development but is not essential for mitochondrial respiration. J. Biol. Chem. 276, 46160–46164 (2001).

    Article  CAS  PubMed  Google Scholar 

  21. Liu, X. et al. Evolutionary conservation of the clk-1-dependent mechanism of longevity: loss of mclk1 increases cellular fitness and lifespan in mice. Genes Dev. 19, 2424–2434 (2005).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  22. Felkai, S. et al. CLK-1 controls respiration, behavior and aging in the nematode Caenorhabditis elegans. EMBO J. 18, 1783–1792 (1999).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Jiang, N., Levavasseur, F., McCright, B., Shoubridge, E. A. & Hekimi, S. Mouse CLK-1 is imported into mitochondria by an unusual process that requires a leader sequence but no membrane potential. J. Biol. Chem. 276, 29218–29225 (2001).

    Article  CAS  PubMed  Google Scholar 

  24. Wright, G., Terada, K., Yano, M., Sergeev, I. & Mori, M. Oxidative stress inhibits the mitochondrial import of preproteins and leads to their degradation. Exp. Cell Res. 263, 107–117 (2001).

    Article  CAS  PubMed  Google Scholar 

  25. Yang, W. & Hekimi, S. A mitochondrial superoxide signal triggers increased longevity in Caenorhabditis elegans. PLoS Biol. 8, e1000556 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Van Raamsdonk, J. M. et al. Decreased energy metabolism extends life span in Caenorhabditis elegans without reducing oxidative damage. Genetics 185, 559–571 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Matés, J. M. et al. Glutamine homeostasis and mitochondrial dynamics. Int. J. Biochem. Cell Biol. 41, 2051–2061 (2009).

    Article  CAS  PubMed  Google Scholar 

  28. Suzuki, S. et al. Phosphate-activated glutaminase (GLS2), a p53-inducible regulator of glutamine metabolism and reactive oxygen species. Proc. Natl Acad. Sci. USA 107, 7461–7466 (2010).

    Article  PubMed  PubMed Central  Google Scholar 

  29. O’Keefe, L. V. et al. Drosophila orthologue of WWOX, the chromosomal fragile site FRA16D tumour suppressor gene, functions in aerobic metabolism and regulates reactive oxygen species. Hum. Mol. Genet. 20, 497–509 (2011).

    Article  CAS  PubMed  Google Scholar 

  30. Cristina, D., Cary, M., Lunceford, A., Clarke, C. & Kenyon, C. A regulated response to impaired respiration slows behavioral rates and increases lifespan in Caenorhabditis elegans. PLoS Genet. 5, e1000450 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Itoh, K., Ye, P., Matsumiya, T., Tanji, K. & Ozaki, T. Emerging functional cross-talk between the Keap1-Nrf2 system and mitochondria. J. Clin. Biochem Nutr. 56, 91–97 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Papa, L. & Germain, D. Estrogen receptor mediates a distinct mitochondrial unfolded protein response. J. Cell Sci. 124, 1396–1402 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. Aldridge, J. E., Horibe, T. & Hoogenraad, N. J. Discovery of genes activated by the mitochondrial unfolded protein response (mtUPR) and cognate promoter elements. PloS ONE 2, e874 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Kayser, E. B., Sedensky, M. M., Morgan, P. G. & Hoppel, C. L. Mitochondrial oxidative phosphorylation is defective in the long-lived mutant clk-1. J. Biol. Chem. 279, 54479–54486 (2004).

    Article  CAS  PubMed  Google Scholar 

  35. Hall, D. A. et al. Regulation of gene expression by a metabolic enzyme. Science 306, 482–484 (2004).

    Article  CAS  PubMed  Google Scholar 

  36. Lee, S. J., Hwang, A. B. & Kenyon, C. Inhibition of respiration extends C. elegans life span via reactive oxygen species that increase HIF-1 activity. Curr. Biol. 20, 2131–2136 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  37. Owusu-Ansah, E., Song, W. & Perrimon, N. Muscle mitohormesis promotes longevity via systemic repression of insulin signaling. Cell 155, 699–712 (2013).

    Article  CAS  PubMed  Google Scholar 

  38. Yogev, O. & Pines, O. Dual targeting of mitochondrial proteins: mechanism, regulation and function. Biochim. Biophys. Acta 1808, 1012–1020 (2011).

    Article  CAS  PubMed  Google Scholar 

  39. Yogev, O. et al. Fumarase: a mitochondrial metabolic enzyme and a cytosolic/nuclear component of the DNA damage response. PLoS Biol. 8, e1000328 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  40. Chueh, F. Y. et al. Nuclear localization of pyruvate dehydrogenase complex-E2 (PDC-E2), a mitochondrial enzyme, and its role in signal transducer and activator of transcription 5 (STAT5)-dependent gene transcription. Cell. Signal. 23, 1170–1178 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  41. Sutendra, G. et al. A nuclear pyruvate dehydrogenase complex is important for the generation of acetyl-CoA and histone acetylation. Cell 158, 84–97 (2014).

    Article  CAS  PubMed  Google Scholar 

  42. Bar-Peled, M. & Raikhel, N. V. A method for isolation and purification of specific antibodies to a protein fused to the GST. Anal. Biochem. 241, 140–142 (1996).

    Article  CAS  PubMed  Google Scholar 

  43. Whitmarsh, A. J. & Davis, R. J. Analyzing JNK and p38 mitogen-activated protein kinase activity. Methods Enzymol. 332, 319–336 (2001).

    Article  CAS  PubMed  Google Scholar 

  44. Frezza, C., Cipolat, S. & Scorrano, L. Organelle isolation: functional mitochondria from mouse liver, muscle and cultured fibroblasts. Nat. Protoc. 2, 287–295 (2007).

    Article  CAS  PubMed  Google Scholar 

  45. Livak, K. J. & Schmittgen, T. D. Analysis of relative gene expression data using real-time quantitative PCR and the 2(-ΔΔ C(T)) method. Methods 25, 402–408 (2001).

    Article  CAS  PubMed  Google Scholar 

  46. Miyadera, H. et al. Quinones in long-lived clk-1 mutants of Caenorhabditis elegans. FEBS Lett. 512, 33–37 (2002).

    Article  CAS  PubMed  Google Scholar 

  47. Wang, Y. et al. The anti-neurodegeneration drug clioquinol inhibits the aging-associated protein CLK-1. J. Biol. Chem. 284, 314–323 (2009).

    Article  CAS  PubMed  Google Scholar 

  48. Mirzoeva, O. K. & Petrini, J. H. DNA replication-dependent nuclear dynamics of the Mre11 complex. Mol. Cancer Res. 1, 207–218 (2003).

    CAS  PubMed  Google Scholar 

  49. Aparicio, O. et al. Chromatin immunoprecipitation for determining the association of proteins with specific genomic sequences in vivo. Curr. Protoc. Mol. Biol. http://dx.doi.org/10.1002/0471143030.cb1707s23 (2005).

  50. Brenner, S. The genetics of Caenorhabditis elegans. Genetics 77, 71–94 (1974).

    CAS  PubMed  PubMed Central  Google Scholar 

  51. Frokjaer-Jensen, C. et al. Single-copy insertion of transgenes in Caenorhabditis elegans. Nat. Genet. 40, 1375–1383 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  52. Zeiser, E., Frokjaer-Jensen, C., Jorgensen, E. & Ahringer, J. MosSCI and gateway compatible plasmid toolkit for constitutive and inducible expression of transgenes in the C. elegans germline. PloS ONE 6, e20082 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  53. Lakowski, B. & Hekimi, S. Determination of life-span in Caenorhabditis elegans by four clock genes. Science 272, 1010–1013 (1996).

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

We thank I. Donaldson and A. Hayes of the Bioinformatics and Genomic Technologies Core Facilities at the University of Manchester for providing support with regard to ChIP–chip tiling arrays. We thank M. Howard for assistance with RP-HPLC. This work was supported by the Biotechnology and Biological Sciences Research Council (BB/J014834/1 to A.J.W. and G.B.P.) and the Wellcome Trust (093176/Z/10/Z to A.J.W. and 097820/Z/11/Z to A.J.W. and G.B.P.). Some strains were provided by the Caenorhabditis Genetics Center, which is funded by NIH Office of Research Infrastructure Programs (P40 OD010440). We thank A. Sharrocks, P. Shore, S. H. Yang and A. Gilmore for helpful comments on the manuscript.

Author information

Author notes

  1. Tereza Andreou & Nicholas Rooney

    Present address: Present addresses: Institute of Cancer and Pathology, University of Leeds, St James’s University Hospital, Leeds LS9 7TF, UK (T.A.); The Beatson Institute for Cancer Research, Switchback Road, Bearsden, Glasgow G61 1BD, UK (N.R.).,

Authors and Affiliations

  1. Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road Manchester M13 9PT, UK,

    Richard M. Monaghan, Robert G. Barnes, Kate Fisher, Tereza Andreou, Nicholas Rooney, Gino B. Poulin & Alan J. Whitmarsh

Authors
  1. Richard M. Monaghan
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Robert G. Barnes
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Kate Fisher
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Tereza Andreou
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Nicholas Rooney
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Gino B. Poulin
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Alan J. Whitmarsh
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

R.M.M. conceived and designed the study, performed most of the experiments, analysed the data and wrote the paper; R.G.B. generated worm strains, imaged worms and conducted lifespan experiments; K.F. generated worm strains; T.A. and N.R. screened non-nuclear COQ7 mutants; G.B.P. conceived and designed the study; A.J.W. conceived and designed the study, analysed the data and wrote the paper.

Corresponding authors

Correspondence to Gino B. Poulin or Alan J. Whitmarsh.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Integrated supplementary information

Supplementary Figure 1 A distinct pool of COQ7 localises to nuclei.

(a) HeLa cells expressing COQ7-Myc were scored for mitochondrial, nuclear, mitochondrial and nuclear, or disperse COQ7 immunostaining (40 cells assessed in each of n = 3 independent experiments; error bars, s.e.m. ∗∗P < 0.005 compared to other localisations). Representative image of cells is shown in Fig. 1b. (b) The region of COQ7 required for specific nuclear localisation resides between amino acids 11 and 29. GFP fluorescence of COS7 cells expressing GFP-COQ7 and the deletion mutants GFP-COQ7(11-217), lacking amino acids 1-10, and GFP-COQ7(30-217), lacking amino acids 1-29. Orientating the GFP tag on the N-terminus of COQ7 abolished mitochondrial localisation and promoted nuclear localisation, probably due to disruption of the interaction between the N-terminal MTS and the mitochondrial import machinery. Mitochondria are stained with MitoTracker (MT) and nuclei with DAPI. Schematic depicts the GFP-COQ7 deletion mutants used and summarises their localisation. (c) Endogenous uncleaved COQ7 is nuclear. HeLa cells immunostained with a second antibody specific to the N-terminus of COQ7 (COQ7N−term2). Nuclei are stained with DAPI. (d) Immunoblot demonstrating that uncleaved wild type COQ7 (WT) migrates at the same position as COQ7 S36A (containing a point mutation in the predicted mitochondrial processing peptidase cleavage site) and that cleaved COQ7 migrates at the same position as COQ7(37-217) that lacks the N-terminal region cleaved by MPP. ∗ denotes partial cleavage of COQ7 S36A at a site upstream of the predicted MPP site. (e) The intensity of nuclear anti-Myc immunostaining in HeLa cells expressing COQ7-Myc or COQ7-R11/14/16D-Myc was quantified. Cells were treated with H2O2 (150 μM, 4 h) or NAC (10 mM, 6 h). 50 cells assessed in each of n = 3 independent experiments; error bars, s.e.m. n.s., no significant difference; ∗P < 0.05 relative to untreated.

Supplementary Figure 2 Identifying a non-nuclear mutant of COQ7.

(a) Alignment of mammalian COQ7 N-terminal protein sequences (amino acids 1 to 42) using Clone Manager (Sci-Ed Software); HS, Homo sapiens; CL, Canis lupus familiaris; MM, Mus musculus; RN, Rattus norvegicus. Conserved residues are in red and R28 is in blue. MPP marks the predicted mitochondrial processing peptidase cleavage site. Residues mutated and assessed in the fluorescence studies in panel b are denoted with asterisks. (b) Point mutations in the COQ7 N-terminus cause reduced nuclear localisation. GFP fluorescence in COS7 cells expressing COQ7 fused at the C-terminus to GFP and harboring the point mutations R21A, Y26F and R28A were analysed. Quantification of the percent of cells displaying nuclear staining is shown (100 cells assessed in each of n = 3 independent experiments; error bars, s.e.m. ∗∗P < 0.005). The most severe loss of nuclear staining was observed with the R28A mutation. (c) COQ7 (R28A) mutant displays reduced levels of the uncleaved form. Lysates from HEK293 cells expressing OLLAS and FLAG tagged COQ7 (COQ7O/F) or COQ7(R28A)O/F (Fig. 2b) were immunoblotted with anti-COQ7 antibody. (d) Parent HEK293 cells (Ctrl) or cells stably expressing untagged (WT) or non-nuclear COQ7 (R28A) were transfected with siCTRL or siCOQ7that specifically targets endogenous COQ7 mRNA. Transcript levels of endogenous COQ7 mRNA (5′UTR amplicon) were analysed (mean values from 3 reactions per condition in n = 4 independent experiments; error bars, s.e.m. ∗∗P < 0.005). (e) Reverse phase HPLC chromatograms of quinones. Purified ubiquinone-10 (UQ10) was used as a standard. Levels of UQ10 and demethoxyubiquinone-10 (DMQ10) were measured in HEK293 cells treated with the COQ7 inhibitor clioquinol (CQ; 10 μM, 24 h), or from WT or R28A expressing HEK293 cells. CQ caused the appearance of DMQ10. UQ10 peak at 8.63 min, DMQ10 peak at 8.39 min. (f) Levels of lactate dehydrogenase (LDH) in media from cultured WT and R28A cells are similar, indicating that cell survival under basal conditions is not changed (mean values from 4 wells of cells per condition in n = 3 independent experiments; error bars, s.e.m. ∗∗P < 0.005). Treatment with 0.1% (v/v) Triton X-100 (TX) for 30 min was used as a positive control.

Supplementary Figure 3 Nuclear CLK-1/COQ7 regulates ROS metabolic gene expression.

(a) Nuclear CLK-1 regulates the expression of genes involved in ROS metabolism. qPCR analysis of transcripts from ROS-sensitive retrograde genes (mean values from 3 reactions per condition in n = 3 independent experiments; error bars, s.e.m. ∗P < 0.05 for clk-1(−) compared to other strains). (b) CLK-1nuc(+) rescues the increased transcript levels of genes known to be responsive to ROS (sod-2 and skn-1) in clk-1 null worms (mean values from 3 reactions per condition in n = 3 independent experiments; error bars, s.e.m. ∗P < 0.05 for clk-1(−) compared to other strains). (c) Human homologues of these genes, SOD2 and NRF2, and the NRF2 target gene HMOX1 are increased in cells that have lost nuclear COQ7 (R28A) (mean values from 3 reactions per condition for n = 4 independent experiments; error bars, s.e.m. ∗P < 0.05). (d) Quantification of immunoblots for GLS2, WWOX and HTRA2 proteins (mean values from n = 3 independent experiments; error bars, s.e.m. ∗P < 0.05,∗P < 0.005). Representative blots are shown in Fig. 4i.

Supplementary Figure 4 Nuclear CLK-1/COQ7 suppresses the expression of UPRmt genes.

(a) qPCR analysis of UPRmt genes in CLK-1 transgenic worm strains relative to N2 (mean values from 3 reactions per condition in n = 3 independent experiments; error bars, s.e.m. n.s., no significant difference; ∗P < 0.05). The increase in expression of hsp-6, hsp-60 and spg-7 in clk-1(−) worms was abrogated by expression of either CLK-1wt or CLK-1nuc(+). mRNA levels of the endoplasmic reticulum UPR (UPRER)-regulated gene hsp-4 were not changed in any of the worm strains. (b) qPCR of analysis of transcripts of UPRmt genes and UPRER genes in WT and R28A expressing HEK293 cells (mean values from 3 reactions per condition in n = 4 independent experiments; error bars, s.e.m. ∗P < 0.05.∗∗P < 0.005). Heatmap of this data is shown in Fig. 6c. (c) The ratio of COXIV to MTCO1 protein levels in WT and R28A expressing cells quantified from n = 3 independent immunoblots (error bars, s.e.m. n.s., no significant difference). See Fig. 6d for representative immunoblot.

Supplementary Figure 5 Uncropped scans of western blots.

Supplementary information

Supplementary Information

Supplementary Information (PDF 763 kb)

Supplementary Table 1

Supplementary Information (XLSX 10 kb)

Supplementary Table 2

Supplementary Information (XLS 1951 kb)

Supplementary Table 3

Supplementary Information (XLSX 48 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Monaghan, R., Barnes, R., Fisher, K. et al. A nuclear role for the respiratory enzyme CLK-1 in regulating mitochondrial stress responses and longevity. Nat Cell Biol 17, 782–792 (2015). https://doi.org/10.1038/ncb3170

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ncb3170

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing