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Light-harvesting complex II is an antenna of photosystem I in dark-adapted plants


Photosystem I (PSI) is a major player in the light reactions of photosynthesis. In higher plants, it consists of a core complex and four external antennae, Lhca1–4 forming the PSI–light-harvesting complex I (LHCI) supercomplex. The protein and pigment composition as well as the spectroscopic properties of this complex are considered to be identical in different higher plant species. In addition to the four Lhca, a pool of mobile LHCII increases the antenna size of PSI under most light conditions. In this work, we have first investigated purified PSI complexes and then PSI in vivo upon long-term dark-adaptation of four well-studied plant species: Arabidopsis thaliana, Zea mays, Nicotiana tabacum and Hordeum vulgare. By performing time-resolved fluorescence measurements, we show that LHCII is associated with PSI also in a dark-adapted state in all the plant species investigated. The number of LHCII subunits per PSI is plant-dependent, varying between one and three. Furthermore, we show that the spectroscopic properties of PSI–LHCI supercomplexes differ in different plants.

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Fig. 1: Protein composition and spectra of PSI–LHCI isolated from four plant species.
Fig. 2: Time-resolved fluorescence results of the PSI–LHCI complexes.
Fig. 3: Time-resolved fluorescence measurements upon 662-nm excitation on leaves of A. thaliana WT.
Fig. 4: PSI-related DAS obtained for intact leaves.

Data availability

The raw data that support the findings of this study are available from the corresponding author upon reasonable request. Source data are provided with this paper.


  1. 1.

    Jansson, S. A guide to the Lhc genes and their relatives in Arabidopsis. Trends Plant Sci. 4, 236–240 (1999).

    CAS  PubMed  Google Scholar 

  2. 2.

    Croce, R. & van Amerongen, H. Light-harvesting in photosystem I. Photosynth. Res. 116, 153–166 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  3. 3.

    Mazor, Y., Borovikova, A. & Nelson, N. The structure of plant photosystem I super-complex at 2.8 Å resolution. eLife 4, e07433 (2015).

    PubMed  PubMed Central  Google Scholar 

  4. 4.

    Qin, X., Suga, M., Kuang, T. & Shen, J. R. Photosynthesis. Structural basis for energy transfer pathways in the plant PSI–LHCI supercomplex. Science 348, 989–995 (2015).

    CAS  Google Scholar 

  5. 5.

    Allen, J. F. Botany. State transitions—a question of balance. Science 299, 1530–1532 (2003).

    CAS  PubMed  Google Scholar 

  6. 6.

    Allen, J. F. Plastoquinone redox control of chloroplast thylakoid protein phosphorylation and distribution of excitation energy between photosystems: discovery, background, implications. Photosynth. Res. 73, 139–148 (2002).

    CAS  PubMed  Google Scholar 

  7. 7.

    Osmond, B., Chow, W. S., Pogson, B. J. & Robinson, S. A. Probing functional and optical cross-sections of PSII in leaves during state transitions using fast repetition rate light induced fluorescence transients. Funct. Plant Biol. 46, 567–583 (2019).

    CAS  PubMed  Google Scholar 

  8. 8.

    Wood, W. H. J., Barnett, S. F. H., Flannery, S., Hunter, C. N. & Johnson, M. P. Dynamic thylakoid stacking is regulated by LHCII phosphorylation but not its interaction with PSI. Plant Physiol. 180, 2152–2166 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

  9. 9.

    Ancín, M. et al. Overexpression of thioredoxin m in tobacco chloroplasts inhibits the protein kinase STN7 and alters photosynthetic performance. J. Exp. Bot. 70, 1005–1016 (2019).

    PubMed  Google Scholar 

  10. 10.

    Mekala, N. R., Suorsa, M., Rantala, M., Aro, E.-M. & Tikkanen, M. Plants actively avoid state transitions upon changes in light intensity: role of light-harvesting complex II protein dephosphorylation in high light. Plant Physiol. 168, 721–734 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  11. 11.

    Wientjes, E., van Amerongen, H. & Croce, R. LHCII is an antenna of both photosystems after long-term acclimation. Biochim. Biophys. Acta Bioenerg. 1827, 420–426 (2013).

    CAS  Google Scholar 

  12. 12.

    Allen, J. F. Why we need to know the structure of phosphorylated chloroplast light-harvesting complex II. Physiol. Plant. 161, 28–44 (2017).

    CAS  PubMed  Google Scholar 

  13. 13.

    Bos, P. et al. Digitonin-sensitive LHCII enlarges the antenna of photosystem I in stroma lamellae of Arabidopsis thaliana after far-red and blue-light treatment. Biochim. Biophys. Acta Bioenerg. 1860, 651–658 (2019).

    CAS  PubMed  Google Scholar 

  14. 14.

    Galka, P. et al. Functional analyses of the plant photosystem I–light-harvesting complex II supercomplex reveal that light-harvesting complex II loosely bound to photosystem II Is a very efficient antenna for photosystem I in state II. Plant Cell 24, 2963–2978 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  15. 15.

    Kouřil, R. et al. Structural characterization of a complex of photosystem I and light-harvesting complex II of Arabidopsis thaliana. Biochemistry 44, 10935–10940 (2005).

    PubMed  Google Scholar 

  16. 16.

    Pan, X. et al. Structure of the maize photosystem I supercomplex with light-harvesting complexes I and II. Science 360, 1109–1113 (2018).

    CAS  PubMed  Google Scholar 

  17. 17.

    Bell, A. J., Frankel, L. K. & Bricker, T. M. High yield non-detergent isolation of photosystem I–light-harvesting chlorophyll II membranes from spinach thylakoids: implications for the organization of the PS I antennae in higher plants. J. Biol. Chem. 290, 18429–18437 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  18. 18.

    Bos, I. et al. Multiple LHCII antennae can transfer energy efficiently to a single photosystem I. Biochim. Biophys. Acta Bioenerg. 1858, 371–378 (2017).

    CAS  PubMed  Google Scholar 

  19. 19.

    Yadav, K. N. et al. Supercomplexes of plant photosystem I with cytochrome b6f, light-harvesting complex II and NDH. Biochim. Biophys. Acta Bioenerg. 1858, 12–20 (2017).

    CAS  PubMed  Google Scholar 

  20. 20.

    Benson, S. L. et al. An intact light harvesting complex I antenna system is required for complete state transitions in Arabidopsis. Nat. Plants 1, 15176 (2015).

    CAS  PubMed  Google Scholar 

  21. 21.

    Akhtar, P. et al. Excitation energy transfer between light-harvesting complex II and photosystem I in reconstituted membranes. Biochim. Biophys. Acta Bioenerg. 1857, 462–472 (2016).

    CAS  Google Scholar 

  22. 22.

    Mazor, Y., Borovikova, A., Caspy, I. & Nelson, N. Structure of the plant photosystem I supercomplex at 2.6 Å resolution. Nat. Plants 3, 1–9 (2017).

    Google Scholar 

  23. 23.

    Nelson, N. & Junge, W. Structure and energy transfer in photosystems of oxygenic photosynthesis. Annu. Rev. Biochem. 84, 659–683 (2015).

    CAS  PubMed  Google Scholar 

  24. 24.

    Wientjes, E., van Stokkum, I. H., van Amerongen, H. & Croce, R. The role of the individual Lhcas in photosystem I excitation energy trapping. Biophys. J. 101, 745–754 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  25. 25.

    Croce, R., Dorra, D., Holzwarth, A. R. & Jennings, R. C. Fluorescence decay and spectral evolution in intact photosystem I of higher plants. Biochemistry 39, 6341–6348 (2000).

    CAS  PubMed  Google Scholar 

  26. 26.

    Santabarbara, S., Tibiletti, T., Remelli, W. & Caffarri, S. Kinetics and heterogeneity of energy transfer from light harvesting complex II to photosystem I in the supercomplex isolated from Arabidopsis. Phys. Chem. Chem. Phys. 19, 9210–9222 (2017).

    CAS  PubMed  Google Scholar 

  27. 27.

    Ihalainen, J. A. et al. Excitation energy trapping in photosystem I complexes depleted in Lhca1 and Lhca4. FEBS Lett. 579, 4787–4791 (2005).

    CAS  PubMed  Google Scholar 

  28. 28.

    Morosinotto, T., Breton, J., Bassi, R. & Croce, R. The nature of a chlorophyll ligand in Lhca proteins determines the far red fluorescence emission typical of photosystem I. J. Biol. Chem. 278, 49223–49229 (2003).

    CAS  PubMed  Google Scholar 

  29. 29.

    Jennings, R. C., Zucchelli, G. & Santabarbara, S. Photochemical trapping heterogeneity as a function of wavelength, in plant photosystem I (PSI–LHCI). Biochim. Biophys. Acta Bioenerg. 1827, 779–785 (2013).

    CAS  Google Scholar 

  30. 30.

    van Oort, B. et al. Picosecond fluorescence of intact and dissolved PSI–LHCI crystals. Biophys. J. 95, 5851–5861 (2008).

    PubMed  PubMed Central  Google Scholar 

  31. 31.

    Le Quiniou, C. et al. PSI–LHCI of Chlamydomonas reinhardtii: increasing the absorption cross section without losing efficiency. Biochim. Biophys. Acta Bioenerg. 1847, 458–467 (2015).

    Google Scholar 

  32. 32.

    van Oort, B. et al. Effect of antenna-depletion in photosystem II on excitation energy transfer in Arabidopsis thaliana. Biophys. J. 98, 922–931 (2010).

    PubMed  PubMed Central  Google Scholar 

  33. 33.

    Chukhutsina, V. U., Büchel, C. & van Amerongen, H. Variations in the first steps of photosynthesis for the diatom Cyclotella meneghiniana grown under different light conditions. Biochim. Biophys. Acta Bioenerg. 1827, 10–18 (2013).

    CAS  Google Scholar 

  34. 34.

    Wientjes, E., van Amerongen, H. & Croce, R. Quantum yield of charge separation in photosystem II: functional effect of changes in the antenna size upon light acclimation. J. Phys. Chem. B 117, 11200–11208 (2013).

    CAS  PubMed  Google Scholar 

  35. 35.

    Chukhutsina, V., Bersanini, L., Aro, E.-M. & van Amerongen, H. Cyanobacterial flv4-2 operon-encoded proteins optimize light harvesting and charge separation in photosystem II. Mol. Plant 8, 747–761 (2015).

    CAS  PubMed  Google Scholar 

  36. 36.

    Tian, L., Xu, P., Chukhutsina, V. U., Holzwarth, A. R. & Croce, R. Zeaxanthin-dependent nonphotochemical quenching does not occur in photosystem I in the higher plant Arabidopsis thaliana. Proc. Natl Acad. Sci. USA 114, 4828–4832 (2017).

    CAS  PubMed  Google Scholar 

  37. 37.

    Wientjes, E. & Croce, R. PMS: photosystem I electron donor or fluorescence quencher. Photosynth. Res. 111, 185–191 (2012).

    CAS  PubMed  Google Scholar 

  38. 38.

    Miloslavina, Y. et al. Charge separation kinetics in intact photosystem II core particles is trap-limited. A picosecond fluorescence study. Biochemistry 45, 2436–2442 (2006).

    CAS  PubMed  Google Scholar 

  39. 39.

    Szczepaniak, M. et al. Charge separation, stabilization, and protein relaxation in photosystem II core particles with closed reaction center. Biophys. J. 96, 621–631 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  40. 40.

    Tian, L., Farooq, S. & van Amerongen, H. Probing the picosecond kinetics of the photosystem II core complex in vivo. Phys. Chem. Chem. Phys. 15, 3146–3154 (2013).

    CAS  PubMed  Google Scholar 

  41. 41.

    Wientjes, E., van Stokkum, I. H., van Amerongen, H. & Croce, R. Excitation-energy transfer dynamics of higher plant photosystem I light-harvesting complexes. Biophys. J. 100, 1372–1380 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  42. 42.

    Schatz, G. H., Brock, H. & Holzwarth, A. R. Kinetic and energetic model for the primary processes in photosystem II. Biophys. J. 54, 397–405 (1988).

    CAS  PubMed  PubMed Central  Google Scholar 

  43. 43.

    Tian, L., van Stokkum, I. H., Koehorst, R. B. & van Amerongen, H. Light harvesting and blue-green light induced non-photochemical quenching in two different C-phycocyanin mutants of Synechocystis PCC 6803. J. Phys. Chem. B 117, 11000–11006 (2013).

    CAS  PubMed  Google Scholar 

  44. 44.

    Pietrzykowska, M. et al. The light-harvesting chlorophyll a/b binding proteins Lhcb1 and Lhcb2 play complementary roles during state transitions in Arabidopsis. Plant Cell 26, 3646–3660 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  45. 45.

    Amerongen, H. van, Grondelle, R. van & Valkunas, L. Photosynthetic Excitons (World Scientific, 2010).

  46. 46.

    Barter, L. M. C. et al. Relationship between excitation energy transfer, trapping, and antenna size in photosystem II. Biochemistry 40, 4026–4034 (2001).

    CAS  PubMed  Google Scholar 

  47. 47.

    Wientjes, E., Oostergetel, G. T., Jansson, S., Boekema, E. J. & Croce, R. The role of Lhca complexes in the supramolecular organization of higher plant photosystem I. J. Biol. Chem. 284, 7803–7810 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  48. 48.

    Morosinotto, T., Castelletti, S., Breton, J., Bassi, R. & Croce, R. Mutation analysis of Lhca1 antenna complex: low energy absorption forms originate from pigment–pigment interactions. J. Biol. Chem. 77, 36253–36261 (2002).

    Google Scholar 

  49. 49.

    Mozzo, M., Morosinotto, T., Bassi, R. & Croce, R. Probing the structure of Lhca3 by mutation analysis. Biochim. Biophys. Acta Bioenerg. 1757, 1607–1613 (2006).

    CAS  Google Scholar 

  50. 50.

    Croce, R. et al. Origin of the 701-nm fluorescence emission of the Lhca2 subunit of higher plant photosystem I. J. Biol. Chem. 279, 48543–48549 (2004).

    CAS  PubMed  Google Scholar 

  51. 51.

    Morosinotto, T., Mozzo, M., Bassi, R. & Croce, R. Pigment–pigment interactions in Lhca4 antenna complex of higher plants photosystem I. J. Biol. Chem. 280, 20612–20619 (2005).

    CAS  PubMed  Google Scholar 

  52. 52.

    Suorsa, M. et al. Light acclimation involves dynamic re-organization of the pigment–protein megacomplexes in non-appressed thylakoid domains. Plant J. 84, 360–373 (2015).

    CAS  PubMed  Google Scholar 

  53. 53.

    Wientjes, E., Drop, B., Kouril, R., Boekema, E. J. & Croce, R. During state 1 to state 2 transition in Arabidopsis thaliana, the photosystem II supercomplex gets phosphorylated but does not disassemble. J. Biol. Chem. 288, 32821–32826 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  54. 54.

    Pribil, M., Pesaresi, P., Hertle, A., Barbato, R. & Leister, D. Role of plastid protein phosphatase TAP38 in LHCII dephosphorylation and thylakoid electron flow. PLoS Biol. 8, e1000288 (2010).

    PubMed  PubMed Central  Google Scholar 

  55. 55.

    Haldrup, A., Jensen, P. E., Lunde, C. & Scheller, H. V. Balance of power: a view of the mechanism of photosynthetic state transitions. Trends Plant Sci. 6, 301–305 (2001).

    CAS  PubMed  Google Scholar 

  56. 56.

    Crepin, A. & Caffarri, S. The specific localizations of phosphorylated Lhcb1 and Lhcb2 isoforms reveal the role of Lhcb2 in the formation of the PSI–LHCII supercomplex in Arabidopsis during state transitions. Biochim. Biophys. Acta Bioenerg. 1847, 1539–1548 (2015).

    CAS  Google Scholar 

  57. 57.

    Longoni, P., Douchi, D., Cariti, F., Fucile, G. & Goldschmidt-Clermont, M. Phosphorylation of the light-harvesting complex II isoform Lhcb2 Is central to state transitions. Plant Physiol. 169, 2874–2883 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  58. 58.

    Xu, P., Tian, L., Kloz, M. & Croce, R. Molecular insights into Zeaxanthin-dependent quenching in higher plants. Sci. Rep. 5, 13679 (2015).

    PubMed  PubMed Central  Google Scholar 

  59. 59.

    Dinc, E., Ramundo, S., Croce, R. & Rochaix, J. D. Repressible chloroplast gene expression in Chlamydomonas: a new tool for the study of the photosynthetic apparatus. Biochim. Biophys. Acta Bioenerg. 1837, 1548–1552 (2014).

    CAS  Google Scholar 

  60. 60.

    Nellaepalli, S., Kodru, S., Tirupathi, M. & Subramanyam, R. Anaerobiosis induced state transition: a non photochemical reduction of PQ pool mediated by NDH in Arabidopsis thaliana. PLoS ONE 7, e49839 (2012).

  61. 61.

    Croce, R., Zucchelli, G., Garlaschi, F. M. & Jennings, R. C. A thermal broadening study of the antenna chlorophylls in PSI-200, LHCI, and PSI core. Biochemistry 37, 17355–17360 (1998).

    CAS  PubMed  Google Scholar 

  62. 62.

    Porra, R. J., Thompson, W. A. & Kriedemann, P. E. Determination of accurate extinction coefficients and simultaneous equations for assaying chlorophylls a and b extracted with four different solvents: verification of the concentration of chlorophyll standards by atomic absorption spectroscopy. Biochim. Biophys. Acta Bioenerg. 975, 384–394 (1989).

    CAS  Google Scholar 

  63. 63.

    Edgar, R. C. MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Res. 32, 1792–1797 (2004).

    CAS  PubMed  PubMed Central  Google Scholar 

  64. 64.

    Chukhutsina, V. U., Holzwarth, A. R. & Croce, R. Time-resolved fluorescence measurements on leaves: principles and recent developments. Photosynth. Res. 140, 355–369 (2018).

    PubMed  PubMed Central  Google Scholar 

  65. 65.

    Digris, A. V. et al. Thermal stability of a flavoprotein assessed from associative analysis of polarized time-resolved fluorescence spectroscopy. Eur. Biophys. J. 28, 526–531 (1999).

    CAS  PubMed  Google Scholar 

  66. 66.

    van Stokkum, I. H. M., Larsen, D. S. & van Grondelle, R. Global and target analysis of time-resolved spectra. Biochim. Biophys. Acta Bioenerg. 1657, 82–104 (2004).

    Google Scholar 

  67. 67.

    Wientjes, E. & Croce, R. The light-harvesting complexes of higher-plant photosystem I: Lhca1/4 and Lhca2/3 form two red-emitting heterodimers. Biochem. J. 433, 477–485 (2011).

    CAS  PubMed  Google Scholar 

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This work was supported by the Dutch Organization for scientific research (NWO) via Vici grant no. 86510013 to R.C. X.L was supported by the China Scholarship Council. We thank R. Fristedt for help with growing the plants.

Author information




R.C. and V.C. conceived the project, designed the study and wrote the manuscript. V.C. performed most of the experiments and data analysis. P.X. and X.L. performed biochemical experiments. All authors revised the manuscript and approved the final version.

Corresponding author

Correspondence to Roberta Croce.

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The authors declare no competing interests.

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Peer review information Nature Plants thanks John Allen, Matthew Johnson and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary Information

Supplementary discussion, Figs. 1–6 and Tables 1 and 2.

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Source Data Fig. 1

Unprocessed SDS–PAGE.

Source Data Supplementary Fig. 4

Unprocessed chemiluminescence signals and Ponceau staining.

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Chukhutsina, V.U., Liu, X., Xu, P. et al. Light-harvesting complex II is an antenna of photosystem I in dark-adapted plants. Nat. Plants 6, 860–868 (2020).

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