HSP70 expression in the Copper butterfly Lycaena tityrus across altitudes and temperatures


Isabell Karl, Department of Animal Ecology I, University of Bayreuth, PO Box 101 251, D-95440 Bayreuth, Germany. Tel.: +49 921 553079; fax: +49 921 552784; e-mail: isabell.karl@uni-bayreuth.de


The ability to express heat-shock proteins (HSP) under thermal stress is an essential mechanism for ectotherms to cope with unfavourable conditions. In this study, we investigate if Copper butterflies originating from different altitudes and/or being exposed to different rearing and induction temperatures show differences in HSP70 expression. HSP70 expression increased substantially at the higher rearing temperature in low-altitude butterflies, which might represent an adaptation to occasionally occurring heat spells. On the other hand, high-altitude butterflies showed much less plasticity in response to rearing temperatures, and overall seem to rely more on genetically fixed thermal stress resistance. Whether the latter indicates a higher vulnerability of high-altitude populations to global warming needs further investigation. HSP70 expression increased with both colder and warmer induction temperatures.