Expressed sequence tags from heat-shocked seagrass Zostera noltii (Hornemann) from its southern distribution range

Abstract

Predicted global climate change threatens the distributional ranges of species worldwide. We identified genes expressed in the intertidal seagrass Zostera noltii during recovery from a simulated low tide heat-shock exposure. Five Expressed Sequence Tag (EST) libraries were compared, corresponding to four recovery times following sub-lethal temperature stress, and a non-stressed control. We sequenced and analyzed 7009 sequence reads from 30min, 2h, 4h and 24h after the beginning of the heat-shock (AHS), and 1585 from the control library, for a total of 8594 sequence reads. Among 51 Tentative UniGenes (TUGs) exhibiting significantly different expression between libraries, 19 (37.3%) were identified as 'molecular chaperones' and were over-expressed following heat-shock, while 12 (23.5%) were 'photosynthesis TUGs' generally under-expressed in heat-shocked plants. A time course analysis of expression showed a rapid increase in expression of the molecular chaperone class, most of which were heat-shock proteins; which increased from 2 sequence reads in the control library to almost 230 in the 30min AHS library, followed by a slow decrease during further recovery. In contrast, 'photosynthesis TUGs' were under-expressed 30min AHS compared with the control library, and declined progressively with recovery time in the stress libraries, with a total of 29 sequence reads 24h AHS, compared with 125 in the control. A total of 4734 TUGs were screened for EST-Single Sequence Repeats (EST-SSRs) and 86 microsatellites were identified.

Climate change and ocean acidification effects on seagrasses and marine macroalgae

“…Initial up-regulation of superoxidase dismutase was found coincident with elevated effective quantum yield (10 s dark adaptation) and electron transfer rates, indicating that seagrass thermal stress is linked to photophysiology and that Z. marina has the capacity to up-regulate anti-oxidative machinery (Reusch et al, 2008). Although heat shock proteins were not shown to be expressed in Z. marina in response to elevated temperatures (Reusch et al, 2008), heat shock proteins (HSP70 family) were up-regulated by the intertidal seagrass Zostera noltii exposed to thermal stress (37°C for 4 h, Massa et al, 2011). At the same time, photosynthesis-related genes were down-regulated with the exception of genes associated with non-photosynthetic quenching and oxidative stress.…”

Genomewide transcriptional reprogramming in the seagrass Cymodocea nodosa under experimental ocean acidification

“…In seagrasses, several studies have published whole transcriptomes of Zostera spp. ( Z. marina and Z. noltii ), obtained via sequencing cDNA libraries and 454 pyrosequencing (Franssen et al., , ; Gu et al., ; Massa et al., ; Reusch et al., ; Wissler et al., , ) or, more recently, via Illumina sequencing technology (Kong, Li, Sun, Zhou, & Mao, ), under a range of environmental conditions (e.g., temperature, salinity, light intensity and quality). However, the effects of either short‐ or long‐term exposure to elevated CO 2 and low pH have not been assessed so far.…”

Response of the seagrass Posidonia oceanica to different light environments: Insights from a combined molecular and photo-physiological study

“…The recent development of molecular resources for different seagrass species (e.g. Franssen et al, 2011;Wissler et al, 2009) has greatly facilitated the investigation of differentially expressed genes in response to environmental variations (Bergmann et al, 2010;Bruno et al, 2010;Gu et al, 2012;Massa et al, 2011;Reusch et al, 2008;Serra et al, 2012;Winters et al, 2011), and first attempts have been already carried out in Posidonia oceanica, to couple genomic and eco-physiological approaches (Dattolo et al, 2013;Mazzuca et al, 2013;Procaccini et al, 2012).…”