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:

Cryo-EM structures of complex I from mouse heart mitochondria in two biochemically defined states

Abstract

Complex I (NADH:ubiquinone oxidoreductase) uses the reducing potential of NADH to drive protons across the energy-transducing inner membrane and power oxidative phosphorylation in mammalian mitochondria. Recent cryo-EM analyses have produced near-complete models of all 45 subunits in the bovine, ovine and porcine complexes and have identified two states relevant to complex I in ischemia–reperfusion injury. Here, we describe the 3.3-Å structure of complex I from mouse heart mitochondria, a biomedically relevant model system, in the ‘active’ state. We reveal a nucleotide bound in subunit NDUFA10, a nucleoside kinase homolog, and define mechanistically critical elements in the mammalian enzyme. By comparisons with a 3.9-Å structure of the ‘deactive’ state and with known bacterial structures, we identify differences in helical geometry in the membrane domain that occur upon activation or that alter the positions of catalytically important charged residues. Our results demonstrate the capability of cryo-EM analyses to challenge and develop mechanistic models for mammalian complex I.

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

Access options

Buy this article

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

Fig. 1: Overview of the structure of mouse complex I.
Fig. 2: The resolution of densities for the core and supernumerary subunits in the 3.3-Å-resolution map of active mouse complex I.
Fig. 3: Differences in structure between the active and deactive states of mouse complex I.
Fig. 4: Phospholipids in the 3.3-Å-resolution structure of mouse complex I.
Fig. 5: Nucleotide or nucleoside binding to NDUFA10.
Fig. 6: The environment of cluster N2, the ubiquinone-binding channel and the E-channel in active mouse complex I.
Fig. 7: Charged residues and discontinuous and π-helices in subunits ND2, ND4 and ND5.

Similar content being viewed by others

References

  1. Hirst, J. Mitochondrial complex I. Annu. Rev. Biochem. 82, 551–575 (2013).

    Article  CAS  Google Scholar 

  2. Fassone, E. & Rahman, S. Complex I deficiency: clinical features, biochemistry and molecular genetics. J. Med. Genet. 49, 578–590 (2012).

    Article  CAS  Google Scholar 

  3. Hirst, J., Carroll, J., Fearnley, I. M., Shannon, R. J. & Walker, J. E. The nuclear encoded subunits of complex I from bovine heart mitochondria. Biochim. Biophys. Acta 1604, 135–150 (2003).

    Article  CAS  Google Scholar 

  4. Stroud, D. A. et al. Accessory subunits are integral for assembly and function of human mitochondrial complex I. Nature 538, 123–126 (2016).

    Article  CAS  Google Scholar 

  5. Sazanov, L. A. & Hinchliffe, P. Structure of the hydrophilic domain of respiratory complex I from Thermus thermophilus. Science 311, 1430–1436 (2006).

    Article  CAS  Google Scholar 

  6. Efremov, R. G. & Sazanov, L. A. Structure of the membrane domain of respiratory complex I. Nature 476, 414–420 (2011).

    Article  CAS  Google Scholar 

  7. Baradaran, R., Berrisford, J. M., Minhas, G. S. & Sazanov, L. A. Crystal structure of the entire respiratory complex I. Nature 494, 443–448 (2013).

    Article  CAS  Google Scholar 

  8. Vinothkumar, K. R., Zhu, J. & Hirst, J. Architecture of mammalian respiratory complex I. Nature 515, 80–84 (2014).

    Article  CAS  Google Scholar 

  9. Zhu, J. et al. Structure of subcomplex Iβ of mammalian respiratory complex I leads to new supernumerary subunit assignments. Proc. Natl. Acad. Sci. USA 112, 12087–12092 (2015).

    Article  CAS  Google Scholar 

  10. Zhu, J., Vinothkumar, K. R. & Hirst, J. Structure of mammalian respiratory complex I. Nature 536, 354–358 (2016).

    Article  CAS  Google Scholar 

  11. Fiedorczuk, K. et al. Atomic structure of the entire mammalian mitochondrial complex I. Nature 538, 406–410 (2016).

    Article  CAS  Google Scholar 

  12. Wu, M., Gu, J., Guo, R., Huang, Y. & Yang, M. Structure of mammalian respiratory supercomplex I1III2IV1. Cell 167, 1598–1609 (2016).

    Article  CAS  Google Scholar 

  13. Guo, R., Zong, S., Wu, M., Gu, J. & Yang, M. Architecture of human mitochondrial respiratory megacomplex I2III2IV2. Cell 170, 1247–1257 (2017).

    Article  CAS  Google Scholar 

  14. Zickermann, V. et al. Mechanistic insight from the crystal structure of mitochondrial complex I. Science 347, 44–49 (2015).

    Article  CAS  Google Scholar 

  15. Cooley, R. B., Arp, D. J. & Karplus, P. A. Evolutionary origin of a secondary structure: π-helices as cryptic but widespread insertional variations of α-helices that enhance protein functionality. J. Mol. Biol. 404, 232–246 (2010).

    Article  CAS  Google Scholar 

  16. Kumar, P. & Bansal, M. Dissecting π-helices: sequence, structure and function. FEBS J. 282, 4415–4432 (2015).

    Article  CAS  Google Scholar 

  17. Kaila, V. R. I., Wikström, M. & Hummer, G. Electrostatics, hydration, and proton transfer dynamics in the membrane domain of respiratory complex I. Proc. Natl. Acad. Sci. USA 111, 6988–6993 (2014).

    Article  CAS  Google Scholar 

  18. Sharma, V. et al. Redox-induced activation of the proton pump in the respiratory complex I. Proc. Natl. Acad. Sci. USA 112, 11571–11576 (2015).

    Article  CAS  Google Scholar 

  19. Di Luca, A., Gamiz-Hernandez, A. P. & Kaila, V. R. I. Symmetry-related proton transfer pathways in respiratory complex I. Proc. Natl. Acad. Sci. USA 114, E6314–E6321 (2017).

    Article  Google Scholar 

  20. Haapanen, O. & Sharma, V. Role of water and protein dynamics in proton pumping by respiratory complex I. Sci. Rep. 7, 7747 (2017).

    Article  Google Scholar 

  21. Blaza, J. N., Vinothkumar, K. R. & Hirst, J. Structure of the deactive state of mammalian respiratory complex I. Structure 26, 312–319 (2018).

    Article  CAS  Google Scholar 

  22. Kotlyar, A. B. & Vinogradov, A. D. Slow active/inactive transition of the mitochondrial NADH-ubiquinone reductase. Biochim. Biophys. Acta 1019, 151–158 (1990).

    Article  CAS  Google Scholar 

  23. Vinogradov, A. D. Catalytic properties of the mitochondrial NADH-ubiquinone oxidoreductase (complex I) and the pseudo-reversible active/inactive enzyme transition. Biochim. Biophys. Acta 1364, 169–185 (1998).

    Article  CAS  Google Scholar 

  24. Babot, M., Birch, A., Labarbuta, P. & Galkin, A. Characterisation of the active/de-active transition of mitochondrial complex I. Biochim. Biophys. Acta 1837, 1083–1092 (2014).

    Article  CAS  Google Scholar 

  25. Galkin, A. & Moncada, S. Modulation of the conformational state of mitochondrial complex I as a target for therapeutic intervention. Interface Focus 7, 20160104 (2017).

    Article  Google Scholar 

  26. Galkin, A., Abramov, A. Y., Frakich, N., Duchen, M. R. & Moncada, S. Lack of oxygen deactivates mitochondrial complex I: implications for ischemic injury? J. Biol. Chem. 284, 36055–36061 (2009).

    Article  CAS  Google Scholar 

  27. Chouchani, E. T. et al. Cardioprotection by S-nitrosation of a cysteine switch on mitochondrial complex I. Nat. Med. 19, 753–759 (2013).

    Article  CAS  Google Scholar 

  28. Russo, C. J. & Passmore, L. A. Electron microscopy: ultrastable gold substrates for electron cryomicroscopy. Science 346, 1377–1380 (2014).

    Article  CAS  Google Scholar 

  29. Meyerson, J. R. et al. Self-assembled monolayers improve protein distribution on holey carbon cryo-EM supports. Sci. Rep. 4, 7084 (2014).

    Article  Google Scholar 

  30. Letts, J. A., Fiedorczuk, K. & Sazanov, L. A. The architecture of respiratory supercomplexes. Nature 537, 644–648 (2016).

    Article  CAS  Google Scholar 

  31. Di Luca, A. & Kaila, V. R. I. Global collective motions in the mammalian and bacterial respiratory complex I. Biochim. Biophys. Acta 1859, 326–332 (2018).

    Article  Google Scholar 

  32. Hunte, C. Specific protein-lipid interactions in membrane proteins. Biochem. Soc. Trans. 33, 938–942 (2005).

    Article  CAS  Google Scholar 

  33. Sharpley, M. S., Shannon, R. J., Draghi, F. & Hirst, J. Interactions between phospholipids and NADH:ubiquinone oxidoreductase (complex I) from bovine mitochondria. Biochemistry 45, 241–248 (2006).

    Article  CAS  Google Scholar 

  34. Eriksson, S., Munch-Petersen, B., Johansson, K. & Eklund, H. Structure and function of cellular deoxyribonucleoside kinases. Cell. Mol. Life Sci. 59, 1327–1346 (2002).

    Article  CAS  Google Scholar 

  35. Sabini, E., Hazra, S., Ort, S., Konrad, M. & Lavie, A. Structural basis for substrate promiscuity of dCK. J. Mol. Biol. 378, 607–621 (2008).

    Article  CAS  Google Scholar 

  36. Mikkelsen, N. E. et al. Structural basis for feedback inhibition of the deoxyribonucleoside salvage pathway: studies of the Drosophila deoxyribonucleoside kinase. Biochemistry 42, 5706–5712 (2003).

    Article  CAS  Google Scholar 

  37. Schilling, B. et al. Mass spectrometric identification of a novel phosphorylation site in subunit NDUFA10 of bovine mitochondrial complex I. FEBS Lett. 579, 2485–2490 (2005).

    Article  CAS  Google Scholar 

  38. Elurbe, D. M. & Huynen, M. A. The origin of the supernumerary subunits and assembly factors of complex I: a treasure trove of pathway evolution. Biochim. Biophys. Acta 1857, 971–979 (2016).

    Article  CAS  Google Scholar 

  39. Hirst, J. & Roessler, M. M. Energy conversion, redox catalysis and generation of reactive oxygen species by respiratory complex I. Biochim. Biophys. Acta 1857, 872–883 (2016).

    Article  CAS  Google Scholar 

  40. Carroll, J., Ding, S., Fearnley, I. M. & Walker, J. E. Post-translational modifications near the quinone binding site of mammalian complex I. J. Biol. Chem. 288, 24799–24808 (2013).

    Article  CAS  Google Scholar 

  41. Zwicker, K. et al. The redox-Bohr group associated with iron-sulfur cluster N2 of complex I. J. Biol. Chem. 281, 23013–23017 (2006).

    Article  CAS  Google Scholar 

  42. Le Breton, N. et al. Using hyperfine electron paramagnetic resonance spectroscopy to define the proton-coupled electron transfer reaction at Fe-S cluster N2 in respiratory complex I. J. Am. Chem. Soc. 139, 16319–16326 (2017).

    Article  Google Scholar 

  43. Gamiz-Hernandez, A. P., Jussupow, A., Johansson, M. P. & Kaila, V. R. I. Terminal electron−proton transfer dynamics in the quinone reduction of respiratory complex I. J. Am. Chem. Soc. 139, 16282–16288 (2017).

    Article  CAS  Google Scholar 

  44. Hryc, C. F. et al. Accurate model annotation of a near-atomic resolution cryo-EM map. Proc. Natl. Acad. Sci. USA 114, 3103–3108 (2017).

    Article  CAS  Google Scholar 

  45. Fedor, J. G., Jones, A. J. Y., Di Luca, A., Kaila, V. R. I. & Hirst, J. Correlating kinetic and structural data on ubiquinone binding and reduction by respiratory complex I. Proc. Natl. Acad. Sci. USA 114, 12737–12742 (2017).

    Article  CAS  Google Scholar 

  46. Birrell, J. A. & Hirst, J. Truncation of subunit ND2 disrupts the threefold symmetry of the antiporter-like subunits in complex I from higher metazoans. FEBS Lett. 584, 4247–4252 (2010).

    Article  CAS  Google Scholar 

  47. Belevich, G., Knuuti, J., Verkhovsky, M. I., Wikström, M. & Verkhovskaya, M. Probing the mechanistic role of the long α-helix in subunit L of respiratory complex I from Escherichia coli by site-directed mutagenesis. Mol. Microbiol. 82, 1086–1095 (2011).

    Article  CAS  Google Scholar 

  48. Zhu, S. & Vik, S. B. Constraining the lateral helix of respiratory complex I by cross-linking does not impair enzyme activity or proton translocation. J. Biol. Chem. 290, 20761–20773 (2015).

    Article  CAS  Google Scholar 

  49. Steimle, S. et al. Asp563 of the horizontal helix of subunit NuoL is involved in proton translocation by the respiratory complex I. FEBS Lett. 586, 699–704 (2012).

    Article  CAS  Google Scholar 

  50. Sazinsky, M. H. & Lippard, S. J. Product bound structures of the soluble methane monooxygenase hydroxylase from Methylococcus capsulatus (Bath): protein motion in the α-subunit. J. Am. Chem. Soc. 127, 5814–5825 (2005).

    Article  CAS  Google Scholar 

  51. Calvaruso, M. A. et al. Mitochondrial complex III stabilizes complex I in the absence of NDUFS4 to provide partial activity. Hum. Mol. Genet. 21, 115–120 (2012).

    Article  Google Scholar 

  52. Kimanius, D., Forsberg, B. O., Scheres, S. H. & Lindahl, E. Accelerated cryo-EM structure determination with parallelisation using GPUs in RELION-2. eLife 5, e18722 (2016).

    Article  Google Scholar 

  53. Fernandez-Leiro, R. & Scheres, S. H. W. A pipeline approach to single-particle processing in RELION. Acta Crystallogr. D Struct. Biol. 73, 496–502 (2017).

    Article  CAS  Google Scholar 

  54. Chovancova, E. et al. CAVER 3.0: a tool for the analysis of transport pathways in dynamic protein structures. PLoS Comput. Biol. 8, e1002708 (2012).

    Article  CAS  Google Scholar 

  55. Fernández-Vizarra, E. et al. Isolation of mitochondria for biogenetical studies: an update. Mitochondrion 10, 253–262 (2010).

    Article  Google Scholar 

  56. Carroll, J., Altman, M. C., Fearnley, I. M. & Walker, J. E. Identification of membrane proteins by tandem mass spectrometry of protein ions. Proc. Natl. Acad. Sci. USA 104, 14330–14335 (2007).

    Article  CAS  Google Scholar 

  57. Bridges, H. R., Mohammed, K., Harbour, M. E. & Hirst, J. Subunit NDUFV3 is present in two distinct isoforms in mammalian complex I. Biochim. Biophys. Acta 1858, 197–207 (2017).

    Article  CAS  Google Scholar 

  58. Zheng, S. Q. et al. MotionCor2: anisotropic correction of beam-induced motion for improved cryo-electron microscopy. Nat. Methods 14, 331–332 (2017).

    Article  CAS  Google Scholar 

  59. Zhang, K. Gctf: real-time CTF determination and correction. J. Struct. Biol. 193, 1–12 (2016).

    Article  CAS  Google Scholar 

  60. Pettersen, E. F. et al. UCSF Chimera—a visualization system for exploratory research and analysis. J. Comput. Chem. 25, 1605–1612 (2004).

    Article  CAS  Google Scholar 

  61. Scheres, S. H. W. & Chen, S. Prevention of overfitting in cryo-EM structure determination. Nat. Methods 9, 853–854 (2012).

    Article  CAS  Google Scholar 

  62. Heymann, J. B. & Belnap, D. M. Bsoft: image processing and molecular modeling for electron microscopy. J. Struct. Biol. 157, 3–18 (2007).

    Article  CAS  Google Scholar 

  63. Emsley, P., Lohkamp, B., Scott, W. G. & Cowtan, K. Features and development of Coot. Acta Crystallogr. D Biol. Crystallogr. 66, 486–501 (2010).

    Article  CAS  Google Scholar 

  64. Adams, P. D. et al. PHENIX: a comprehensive Python-based system for macromolecular structure solution. Acta Crystallogr. D Biol. Crystallogr. 66, 213–221 (2010).

    Article  CAS  Google Scholar 

  65. Williams, C. J. et al. MolProbity: more and better reference data for improved all-atom structure validation. Protein Sci. 27, 293–315 (2018).

    Article  CAS  Google Scholar 

  66. Barad, B. A. et al. EMRinger: side chain-directed model and map validation for 3D cryo-electron microscopy. Nat. Methods 12, 943–946 (2015).

    Article  CAS  Google Scholar 

  67. Touw, W. G. et al. A series of PDB-related databanks for everyday needs. Nucleic Acids Res. 43, D364–D368 (2015).

    Article  CAS  Google Scholar 

  68. Krissinel, E. & Henrick, K. Inference of macromolecular assemblies from crystalline state. J. Mol. Biol. 372, 774–797 (2007).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank the staff at the Astbury Biostructure Laboratory, University of Leeds (funded by the University of Leeds and Wellcome Trust 108466/Z/15/Z) and at the UK National Electron Bio-Imaging Centre (eBIC) at the Diamond Light Source for assistance with cryo-EM data collection, the staff at the Phenomics Animal Care Facility, S. Ding and I. Fearnley (Cambridge) for mass spectrometry analyses, and M. Hartley and A. Raine (Cambridge) for IT support. This work was supported by Medical Research Council grant numbers MC_U105663141 (J.H.), MC_UU_00015/2 (J.H.) and MC_UU_00015/5 (C.V.).

Author information

Authors and Affiliations

Authors

Contributions

A.-N.A.A. prepared and characterized mouse complex I assisted by H.R.B. and C.V.; J.N.B. prepared cryo-EM grids and collected data, assisted by S.R. and S.P.M.; A.-N.A.A. and J.N.B. processed cryo-EM data assisted by H.R.B., S.R. and S.P.M.; J.N.B. built the models assisted by A.-N.A.A.; J.H. analyzed and interpreted the models assisted by A.-N.A.A., J.N.B. and H.R.B; J.H. directed the project and wrote the manuscript with input from all authors.

Corresponding author

Correspondence to Judy Hirst.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Integrated supplementary information

Supplementary Figure 1 Resolution estimates of the maps for the active and deactive states of complex I.

a, b: data on the active complex. c, d: data on the deactive complex. The estimated resolutions, defined where the line at FSC = 0.143 crosses the red curve, are 3.3 Å for the active complex (a) and 3.9 Å for the deactive complex (c). In both cases the refined models agree well with the maps, as shown by the map vs. model FSC curves (blue). In b) and d), local resolutions were estimated using the Local Resolution function in RELION with default parameters and plotted using UCSF Chimera.

Supplementary Figure 2

Classification and refinement of the cryo-EM density maps for the active and deactive states of mouse complex I.

Supplementary Figure 3

Example densities (carved at 2 Å radius, threshold level 0.065) drawn from different parts of the map of active mouse complex I.

Supplementary Figure 4

Example densities (carved at 2 Å radius, threshold level 0.04) of phosholipids from the map of active mouse complex I.

Supplementary Figure 5 Mass spectrometry evidence for the phosphorylation of bovine NDUFA10-Ser36.

a) Intact mass measurements revealed two masses for NDUFA10, for the unmodified and singly phosphorylated versions (present at the point of measurement). b) Spectrum of fragment ions produced by ETD of a doubly charged precursor ion 942.48 (m/z) with the precursor ion truncated to 10% relative intensity. The observed neutral peptide mass for the phosphorylated peptide is 1882.955 Da, relative to a calculated mass of 1882.959 Da. The observed peptides are mapped onto the amino acid sequence where the phosphorylation site is marked and c is carbamidomethylcysteine. The z7 and z8 fragments confirm Ser36, rather than Ser33, as the site of phosphorylation. No additional phosphorylated peptides from NDUFA10 were observed.

Supplementary Figure 6

Densities and models for TMH8 in subunits ND2, ND4 and ND5 of mouse complex I (carved at 2 Å radius, threshold level 0.065).

Supplementary information

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Agip, AN.A., Blaza, J.N., Bridges, H.R. et al. Cryo-EM structures of complex I from mouse heart mitochondria in two biochemically defined states. Nat Struct Mol Biol 25, 548–556 (2018). https://doi.org/10.1038/s41594-018-0073-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41594-018-0073-1

This article is cited by

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