Meeting Abstract
P1.158 Friday, Jan. 4 Proteomic changes in the mantle tissue of the mussel congeners Mytilus galloprovincialis and M. trossulus in response to acute heat stress SALZBERG, R*; ZUZOW, M; TOMANEK, L; California Polytechnic State University, San Luis Obispo; California Polytechnic State University, San Luis Obispo; California Polytechnic State University, San Luis Obispo rossjoseph1@gmail.com
The heat-sensitive blue mussel, Mytilus trossulus, is native to the Pacific Coast of North America. Its congener, the more heat-tolerant Mediterranean blue mussel, Mytilus galloprovincialis, has invaded and displaced M. trossulus from the southern part of its distribution range in California. This is hypothesized to be in part due to increases in temperatures related to climate change, giving the invasive species a competitive advantage. In order to identify interspecific differences in thermal tolerance, we conducted a proteomic analysis of mantle tissue in response to acute heat stress. Mussels were acclimated to 13°C for four weeks and exposed to acute heat stress (13°C control, 24°C, 28°C and 32°C) for 1 h and returned to 13°C to recover for 24 h. Proteins from mantle tissue were separated through two-dimensional gel electrophoresis (2D GE). We are currently identifying the proteins using 2D gel image analysis software and tandem mass spectrometry. Previous proteomic analyses of gill tissue from the same experiment indicated that reactive oxygen species (ROS)-producing pathways associated with NADH production and oxidation were down-regulated, while ROS-scavenging NADPH producing pathways were up-regulated during extreme heat stress. In parallel, the more heat-sensitive native M. trossulus showed a decrease in the abundance of oxidative stress protein at 32°C. In contrast, the more heat-tolerant M. galloprovincialis showed increasing abundances of fewer oxidative stress proteins, indicating a possible role for heat-induced ROS production in setting thermal tolerance limits. We are currently testing if similar proteomic changes occur in other tissues, specifically mantle.
