An integrated study to the effects of thermal acclimation in zebrafish. Danio rerio

Changes in environmental temperature can profoundly change species habitats and result in populations facing suboptimal environments. Many aquatic organisms are restricted in terms of migration by their habitat requirements. Also due to anthropogenic migration barriers (both physical as well as chemical), organisms are often left with no choice but to acclimate (or, in the long run, adapt) to their changing environment. The scope of this study is to investigate thermal acclimation in zebrafish by combining data from several levels of biological organization. Zebrafish were acclimated to a higher temperature (8°C increase compared to controls) or a lower temperature (8°C decrease compared to controls) in an acute as well as a prolonged and a chronic scenario (4, 14 and 28 days). General condition of the fish was assessed by determining organismal (condition factor) and biochemical (energy homeostasis) parameters. Data at the transcriptome level (using printed oligonucleotide microarrays containing 15,208 probes and real time PCR) were applied to clarify the mechanisms underlying the thermal acclimation response in zebrafish. Overall design: All three biological replicates of liver samples from acute (4 days) and chronic (28 days) controls (26°), warm acclimation (34°) and cold acclimation (18°) were analyzed using microarrays. An A-optimal interwoven loop design was used in which each sample appeared on an array twice in Cy3 and twice in Cy5, resulting in 36 arrays for 18 samples.