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Fluorescent pigments in corals are photoprotective

Abstract

All reef-forming corals depend on the photosynthesis performed by their algal symbiont, and such corals are therefore restricted to the photic zone. The intensity of light in this zone declines over several orders of magnitude—from high and damaging levels at the surface to extreme shade conditions at the lower limit1. The ability of corals to tolerate this range implies effective mechanisms for light acclimation and adaptation2. Here we show that the fluorescent pigments3,4,5,6,7,8,9 (FPs) of corals provide a photobiological system for regulating the light environment of coral host tissue. Previous studies have suggested that under low light, FPs may enhance light availability4,5. We now report that in excessive sunlight FPs are photoprotective; they achieve this by dissipating excess energy at wavelengths of low photosynthetic activity, as well as by reflecting of visible and infrared light by FP-containing chromatophores. We also show that FPs enhance the resistance to mass bleaching of corals during periods of heat stress, which has implications for the effect of environmental stress on the diversity of reef-building corals, such as enhanced survival of a broad range of corals allowing maintenance of habitat diversity.

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Figure 1: Main types of fluorescent pigments (FPs) in coral polyps.
Figure 2: Photoinhibition and bleaching responses of corals.
Figure 3: Apparent reflectance.
Figure 4: Reconstruction of serial confocal sections through tissues of ‘sun’ and ‘shade’ corals.

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References

  1. Jokiel, P. L. Solar ultraviolet radiation and coral reef epifauna. Science 207, 1069–1071 (1980).

    Article  ADS  CAS  Google Scholar 

  2. Falkowski, P. G., Jokiel, P. L. & Kinzie, R. A. III in Coral Reefs Vol. 25, Ecosystems of the World (ed. Dubinsky, Z.) 89–107 (Elsevier, Amsterdam, 1990).

    Google Scholar 

  3. Kawaguti, S. On the physiology of corals. VI. Study of the pigments. Contrib. Palao Trop. Biol. Station 2, 616–673 (1944).

    Google Scholar 

  4. Kawaguti, S. Effect of the green fluorescent pigment on the productivity of the reef corals. Micronesica 5, 313 ( 1969).

    Google Scholar 

  5. Schlichter, D., Fricke, H. W. & Weber, W. Light harvesting by wavelength transformation in a symbiotic coral of the Red Sea twilight zone. Mar. Biol. 91, 403–407 (1986).

    Article  Google Scholar 

  6. Mazel, C. H. Spectral measurements of fluorescence emission in Caribbean cnidarians. Mar. Ecol. Prog. Ser. 120, 185–191 (1995)

    Article  ADS  Google Scholar 

  7. Salih, A., Hoegh-Guldberg, O. & Cox, G. in Proc. Aust. Coral Reef Soc. Conf. (eds Greenwood, J. G. & Hall, N. J.) 217–230 (School of Marine Science, University of Queensland, Brisbane, 1998).

    Google Scholar 

  8. Matz, M. V. et al. Fluorescent proteins from nonbioluminescent anthozoa species. Nature Biotechnol. 17, 969– 973 (1999)

    Article  CAS  Google Scholar 

  9. Dove, S. G., Hoegh-Guldberg, O. & Ranganathan, S. Major colour patterns of reef-building corals are due to a family of GFP-like proteins. Coral Reefs 19, 197–204 (2000).

    Article  Google Scholar 

  10. Dove, S. G., Takabayashi, M. & Hoegh-Guldberg, O. Isolation and partial characterization of the pink and blue pigments of Pocilloporid and Acroporid corals. Biol. Bull. 189, 288–297 (1995).

    Article  CAS  Google Scholar 

  11. Shimomura, O., Johnson, F. H. & Saiga, Y. Extraction, purification, and properties of aequorin, a bioluminescent protein from the luminous hydromedusan, Aequorea. J. Cell. Comp. Physiol. 77, 305– 312 (1962).

    Google Scholar 

  12. Takabayashi, M. & Hoegh-Guldberg, O. Physiological and ecological differences between pink and brown genotypes of the reef-building coral Pocillopora damicornis. Mar. Biol. 123 , 705–714 (1995).

    Article  Google Scholar 

  13. Veron, J. E. N. Corals of Australia and the Indo-Pacific (Angus & Robertson, Sydney, 1986).

    Google Scholar 

  14. Long, S. P., Humphries, S. & Falkowski, P. G. Photoinhibition of photosynthesis in nature. Annu. Rev. Plant Physiol. Plant Mol. Biol. 45, 633– 662 (1994).

    Article  CAS  Google Scholar 

  15. Brown, B. E. et al. Diurnal changes in photochemical efficiency and xanthophyll concentrations in shallow water reef corals: evidence for photoinhibition and photoprotection. Coral Reefs 18, 99– 105 (1999).

    Article  Google Scholar 

  16. Hoegh-Guldberg, O. & Jones, R. Diurnal variability in photoinhibition and photoprotection in the symbiotic zooxanthellae of corals. Mar. Ecol. Prog. Ser. 22, 520– 519 (1999).

    Google Scholar 

  17. Brown, P. E. et al. Bleaching patterns in reef corals. Nature 404, 142–143 (2000).

    Article  ADS  CAS  Google Scholar 

  18. Salih, A., Hoegh-Guldberg, O. & Cox, G. in Proc. Aust. Coral Reef Soc. Conf. (eds Greenwood, J. G. & Hall, N. J.) 206–216 (School of Marine Science, University of Queensland, Brisbane, 1998).

    Google Scholar 

  19. Jones, R., Hoegh-Guldberg, O., Larkum, A. W. D. & Schreiber, U. Temperature induced bleaching of corals begins with impairment of dark metabolism in zooxanthellae. Plant Cell Environ. 21, 1219–1230 (1998).

    Article  CAS  Google Scholar 

  20. Schreiber, U., Gademan, R., Ralph, P. J. & Larkum, A. W. D. Assessment of photosynthetic performance of Prochloron in Lissoclonium patella in hospite by chlorophyll fluorescence measurements. Plant Cell Physiol 38, 945–951 (1997).

    Article  CAS  Google Scholar 

  21. Glynn, P. W. Coral bleaching: ecological perspective. Coral Reefs 12, 1–17 (1993).

    Article  ADS  Google Scholar 

  22. Hoegh-Guldberg, O. Coral bleaching, climate change and the future of the world's coral reefs. Mar. Freshwat. Res. 50, 839– 866 (1999).

    Article  Google Scholar 

  23. Kühl, M. & Jørgensen, B. B. Spectral light measurements in microbenthic phototrophic communities with a fiber-optic microprobe coupled to a sensitive diode array detector. Limnol. Oceanogr. 37, 1813–1823 (1992).

    Article  ADS  Google Scholar 

  24. Kühl, M. et al. Microenvironment and photosynthesis of zooxanthellae in scleractinian corals studied with microsensors for O2, pH and light. Mar. Ecol. Prog. Ser. 117, 159–172 (1995).

    Article  ADS  Google Scholar 

  25. Falkowski, P. G. & Dubinsky, Z. Light-shade adaptation of Stylophora pistillata, a hermatypic coral from the Gulf of Elat. Nature 289, 172–174 (1981).

    Article  ADS  Google Scholar 

  26. Rowan, R. et al. Landscape ecology of algal symbionts creates variation in episodes of coral bleaching. Nature 388, 265– 269 (1997).

    Article  ADS  CAS  Google Scholar 

  27. Shick, J. M., Lesser, M. P. & Jokiel, P. L. Effects of ultraviolet radiation on corals and other coral reef organisms. Glob. Change Biol. 2, 527–545 (1996).

    Article  ADS  Google Scholar 

  28. Lesser, M. P. Elevated temperature and ultraviolet radiation cause oxidative stress and inhibit photosynthesis of symbiotic dinoflagellates. Limnol. Oceanogr. 41, 271–283 ( 1996).

    Article  ADS  CAS  Google Scholar 

  29. Iglesias-Prieto, R. & Trench, R. K. Acclimation and adaption to irradiance in symbiotic dinoflagellates. II. Response of chlorophyll-protein complexes to different photon-flux densities. Mar. Biol. 130, 23–33 (1997).

    Article  CAS  Google Scholar 

  30. Dunlap, W. C. & Shick, J. M. Ultraviolet radiation-absorbing mycosporine-like amino acids in coral reef organisms: a biochemical and environmental perspective. J. Phycol. 34, 418– 430 (1998).

    Article  Google Scholar 

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Acknowledgements

We thank the Great Barrier Reef Marine Park Authority, especially J. Oliver, R. Berkelmans, M. Russell and U. Engelhart, for financial and logistic support. This work was also supported by an Australian Research Council (ARC) SPIRT PhD award (A.S.) and ARC grants (O. H.-G. and A.L.). M.K. was supported by the Danish Natural Science Research Council. We thank the staff of Heron and One Tree Island research stations for assistance during fieldwork.

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Correspondence to Anya Salih.

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Salih, A., Larkum, A., Cox, G. et al. Fluorescent pigments in corals are photoprotective. Nature 408, 850–853 (2000). https://doi.org/10.1038/35048564

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