Enhanced photoprotection pathways in symbiotic dinoflagellates of shallow-water corals and other cnidarians

Photoinhibition, exacerbated by elevated temperatures, underlies coral bleaching, but sensitivity to photosynthetic loss differs among various phylotypes of Symbiodinium, their dinoflagellate symbionts. Symbiodinium is a common symbiont in many cnidarian species including corals, jellyfish, anemones...

Full description

Saved in:

Bibliographic Details
Published in:	Proceedings of the National Academy of Sciences - PNAS Vol. 105; no. 36; pp. 13674 - 13678
Main Authors:	Reynolds, Jennifer McCabe, Bruns, Brigitte U, Fitt, William K, Schmidt, Gregory W
Format:	Journal Article
Language:	English
Published:	United States National Academy of Sciences 09-09-2008 National Acad Sciences
Subjects:	Animals Antennas Biological Sciences Bleaching Cells Chlorophylls Cnidaria - physiology Cnidaria - radiation effects Coral reefs Corals Dinoflagellida - physiology Dinoflagellida - radiation effects Electrons Emission spectra Fluorescence Genomics Invertebrates Marine Photosystem II Protein Complex - metabolism Proteins Symbiodinium Symbionts Symbiosis Symbiosis - physiology Symbiosis - radiation effects Water
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Photoinhibition, exacerbated by elevated temperatures, underlies coral bleaching, but sensitivity to photosynthetic loss differs among various phylotypes of Symbiodinium, their dinoflagellate symbionts. Symbiodinium is a common symbiont in many cnidarian species including corals, jellyfish, anemones, and giant clams. Here, we provide evidence that most members of clade A Symbiodinium, but not clades B-D or F, exhibit enhanced capabilities for alternative photosynthetic electron-transport pathways including cyclic electron transport (CET). Unlike other clades, clade A Symbiodinium also undergo pronounced light-induced dissociation of antenna complexes from photosystem II (PSII) reaction centers. We propose these attributes promote survival of most cnidarians with clade A symbionts at high light intensities and confer resistance to bleaching conditions that conspicuously impact deeper dwelling corals that harbor non-clade A SYMBIODINIUM:
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 Edited by Elisabeth Gantt, University of Maryland, College Park, MD, and approved July 22, 2008 Author contributions: J.M.R. and G.W.S. designed research; J.M.R., B.U.B., W.K.F., and G.W.S. performed research; B.U.B. and G.W.S. contributed new reagents/analytic tools; J.M.R., W.K.F., and G.W.S. analyzed data; and J.M.R., B.U.B., W.K.F., and G.W.S. wrote the paper.
ISSN:	0027-8424 1091-6490
DOI:	10.1073/pnas.0805187105