Abstract
Copepods are the most abundant multicellular animal group and are often most important component of zooplankton and indicators of local and global climate change. Among this broad group of animals, Calanus sinicus holds an important role in the ecosystems of The East China Sea, The Korea Strait, and The East Sea. By comparing the response of their proteomes to ecologically viable environment changes, this study tried to identify molecular responses accountable for compensation of a change in metabolic rates. Using two-dimensional gel electrophoresis and mass spectrometry on C. sinicus sampled at its native environment, 45 distinct proteins were identified that changed abundance as a function of environment changes i.e., temperature elevation and/or oxygen decrease, and 14 that are only present in proteome adapted to higher temperature/lower oxygen. Although the study failed to find heat shock proteins, the abundance of disulfide-isomerase A3 precursor was higher in species thriving at higher temperatures/lower oxygen. The abundance of proteins responsible for redox homeostasis, DNA maintenance, and chromatin rearrangement was also higher at elevated temperature. Also, the molecular machinery responsible for xenobiotic metabolism is mobilized at higher temperatures/ lower oxygen levels. These data indicate fine adjustment of molecular apparatus in response to changes in living environment.
Keywords: Copepod, proteome, thermal variation, ecology, adaptation, 2D-gel electrophoresis, zooplankton, mass spectrometry