Acute heat stress perturbs cellular function on a variety of levels, leading to protein dysfunction and aggregation, oxidative stress and loss of metabolic homeostasis. If these challenges are not overcome quickly, the stressed organism can die. To better understand the earliest tissue-level responses to heat stress, we examined the proteomic response of gill from Geukensia demissa, an extremely eurythermal mussel from the temperate intertidal zone of eastern North America. We exposed 15°C-acclimated individuals to an acute near-lethal heat stress (45°C) for 1 h, and collected gill samples from 0 to 24 h of recovery. The changes in protein expression we found reveal a coordinated physiological response to acute heat stress: proteins associated with apoptotic processes were increased in abundance during the stress itself (i.e. at 0 h of recovery), while protein chaperones and foldases increased in abundance soon after (3 h). The greatest number of proteins changed abundance at 6 h; these included oxidative stress proteins and enzymes of energy metabolism. Proteins associated with the cytoskeleton and extracellular matrix also changed in abundance starting at 6 h, providing evidence of cell proliferation, migration and tissue remodeling. By 12 h, the response to acute heat stress was diminishing, with fewer stress and structural proteins changing in abundance. Finally, the proteins with altered abundances identified at 24 h suggest a return to the pre-stress anabolic state.
The authors declare no competing or financial interests.
P.A.F. conceived and designed the study, and drafted and revised the manuscript. E.M.B., K.M.C. and K.R.K. developed exposure and proteomics protocols, and performed 2D gel electrophoresis and initial protein identifications.
This research was supported by the National Science Foundation [grant IOS 0920103 to P.A.F.].
Supplementary information available online at http://jeb.biologists.org/lookup/doi/10.1242/jeb.141176.supplemental
- Received April 1, 2016.
- Accepted June 17, 2016.
- © 2016. Published by The Company of Biologists Ltd