Meeting Abstract
18.4 Sunday, Jan. 4 A proteomic analysis of temperature acclimation and heat stress in blue mussel (Mytilus) congeners FIELDS, P.A.**; TOMANEK, L.; ZUZOW, M.J.; CLAUSEN, R.C.; Franklin and Marshall College; Cal Poly San Luis Obispo; Cal Poly San Luis Obispo; Franklin and Marshall College peter.fields@fandm.edu
The blue mussel Mytilus galloprovincialis (M.g.) is invasive along the southern California coast, and has displaced the native M. trossulus (M.t.) there. Physiological and biochemical evidence suggest that M.g. may out-compete M.t. due to relative warm adaptation. Here, we use a proteomics approach to examine the cellular responses of gill from the two species to acclimation temperature (7 or 13C) followed by acute heat shock (HS; 32C). Using two-dimensional electrophoresis, in-gel digestion and mass spectrometry, we have found that the two species respond to acclimation and to HS differently. We identified a series of HS protein (HSP) 70 isoforms that are up-regulated significantly (ANOVA; p < 0.05) in M.g. after HS, whether acclimated to 7 or 13C. The same isoforms are up-regulated after HS in M.t. acclimated to 7C, but they are not up-regulated after HS in M.t. acclimated to 13C. In acclimated animals that did not experience HS, M.t. acclimated to 13C have higher levels of HSP70s than do M.g. acclimated to 13C. Levels are similar in M.g. acclimated to 7 or 13C, and M.t. acclimated to 7C. We have also identified four HSP24 isoforms in both species, two of which are expressed in a pattern similar to that of HSP70s. The other two HSP24s, while showing up-regulation after HS in M.g. acclimated to 13C, show no response in M.t. to HS at either acclimation temperature. These results suggest that M.g. produces a more robust HS response than M.t. after acclimation to 13C, and that the response of M.t. to acclimation at 7C is in some ways similar to the response of M.g. at 13C. Currently, we are using the expression profiles of HSP70 and HSP24 isoforms in the two species to search for other proteins that also are up-regulated in response to acclimation or HS.
