Transcriptomic response to thermal and salinity stress in introduced and native sympatric Palaemon caridean shrimps

摘要

Organisms develop local adaptations to cope with spatially and temporally variable environments\udsuch as estuarine habitats, where abiotic parameters such as salinity and temperature fluctuate\udcontinuously. Studying the regulation of gene expression in a variable environment allows us to\udunderstand the underlying molecular mechanisms of these adaptations and the relative roles of the\udgenetic and plastic response. The transcriptomes of the European native Palaemon longirostris (PL)\udand the introduced P. macrodactylus (PM) shrimps are described and compared after an experiment\udsimulating summer conditions in the Guadalquivir Estuary, Spain. Specimens, collected in the\udGuadalquivir Estuary, were maintained at a temperature and salinity of 20 °C and 5 ppt for the control,\udand 30 °C and 15 ppt for the stress treatment. A large amount of differential gene expression was\udobserved: 16,013 and 2,594 for PL and PM respectively. Functionally annotated unigenes revealed some\uddifferences, with PL seemingly having to face stronger physiological stress than PM. Thus, PM seems\udto have greater resistance than PL under conditions of high temperature and salinity. These results\udconstitute a step forward in the understanding of the underlying molecular mechanisms of genetic\udadaptation of native invertebrates, and alien taxa that have successfully invaded estuaries in temperate\udregions around the world.