DOI: 10.1111/gcb.13702
论文题名: Rapid thermal adaptation in photosymbionts of reef-building corals
作者: Chakravarti L.J. ; Beltran V.H. ; van Oppen M.J.H.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2017
语种: 英语
英文关键词: Acropora hyacinthus
; Acropora sarmentosa
; Symbiodinium
; Acropora cytherea
; Assisted evolution
; Coral bleaching
; Experimental evolution
; Great Barrier Reef
; Thermal stress
英文摘要: Climate warming is occurring at a rate not experienced by life on Earth for 10 s of millions of years, and it is unknown whether the coral-dinoflagellate (Symbiodinium spp.) symbiosis can evolve fast enough to ensure coral reef persistence. Coral thermal tolerance is partly dependent on the Symbiodinium hosted. Therefore, directed laboratory evolution in Symbiodinium has been proposed as a strategy to enhance coral holobiont thermal tolerance. Using a reciprocal transplant design, we show that the upper temperature tolerance and temperature tolerance range of Symbiodinium C1 increased after ~80 asexual generations (2.5 years) of laboratory thermal selection. Relative to wild-type cells, selected cells showed superior photophysiological performance and growth rate at 31°C in vitro, and performed no worse at 27°C; they also had lower levels of extracellular reactive oxygen species (exROS). In contrast, wild-type cells were unable to photosynthesise or grow at 31°C and produced up to 17 times more exROS. In symbiosis, the increased thermal tolerance acquired ex hospite was less apparent. In recruits of two of three species tested, those harbouring selected cells showed no difference in growth between the 27 and 31°C treatments, and a trend of positive growth at both temperatures. Recruits that were inoculated with wild-type cells, however, showed a significant difference in growth rates between the 27 and 31°C treatments, with a negative growth trend at 31°C. There were no significant differences in the rate and severity of bleaching in coral recruits harbouring wild-type or selected cells. Our findings highlight the need for additional Symbiodinium genotypes to be tested with this assisted evolution approach. Deciphering the genetic basis of enhanced thermal tolerance in Symbiodinium and the cause behind its limited transference to the coral holobiont in this genotype of Symbiodinium C1 are important next steps for developing methods that aim to increase coral bleaching tolerance. © 2017 John Wiley & Sons Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/61183
Appears in Collections: 影响、适应和脆弱性
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作者单位: Australian Institute of Marine Science Townsville, Qld Australia; College of Marine and Environmental Sciences James Cook University Townsville, Qld Australia; Australian Research Council Centre of Excellence for Coral Reef Studies James Cook University Townsville, Qld Australia; School of BioSciences University of Melbourne Parkville, Vic. Australia
Recommended Citation:
Chakravarti L.J.,Beltran V.H.,van Oppen M.J.H.. Rapid thermal adaptation in photosymbionts of reef-building corals[J]. Global Change Biology,2017-01-01