Meeting Abstract
Intertidal Mytilus californianus are subjected to rapid changes in temperature and food availability. Understanding how mussels deal with these environmental variables can help us predict how future changes in their environment will affect mussel populations. In mussels, the ability to respond to thermal stress may depend on food availability and previous thermal history, which may be linked to the activity of sirtuins (NAD-dependent deacylases). To better understand the role of sirtuins, we evaluated changes in the whole organism physiology for mussels that had been acclimated to one combination of maximum daily temperature (20 or 30°C) and food ration (0.25 or 1.5% mussel dry weight·day-1). Bivalves filter feed via an exhalant siphon, which they open depending on temperature and food availability; this may be used to assess recovery following the application of a stressor. We obtained baseline siphon activity by monitoring siphon movements using high-definition video in the four groups during the last 48 h of a 3 wk acclimation period. We then exposed a subset of these mussels to sirtuin inhibitors and, following inhibition, subjected all treatment groups to an acute heat stress during emersion (33°C). Siphon activity was recorded during the 48 h following sirtuin inhibition and/or acute heat stress to determine how sirtuins and acclimation can affect recovery and the behavior of mussels. We predict that siphon opening will vary among the low and high food regimes during the baseline measurements, and that mussels that received sirtuin inhibition, as well as those acclimated to low food, will recover more slowly from the acute stress than those that were well fed (funded by NSF IOS-1557500).
