Speaker
Description
Oliver Poole, Karl Wotton
The regulation of muscle tissue is crucial for migration as it directly impacts the efficiency and success of long-distance movement. Migratory birds increase muscle mass prior to migration with subsequent muscle catabolism thought to be important for maintaining optimal power to weight ratios as fuel is used up and as an endogenous source of water and Kreb cycle intermediates. Furthermore, genes associated with repair pathways are also modulated to allow the repair and replenishment of stores during stopover rests when food is available. Migrant insects face many of the same challenges as birds, yet little is known about the seasonal regulation of their flight muscles. Here we survey transcriptomic data to demonstrate wide-spread differences in the expression of muscle transcripts between migrant and non-migrant hoverflies (Diptera: Syrphidae) and between male and female migrants with divergent migratory behaviours. Additionally, we test the ability of these migrants to maintain and recover from multiple bouts of long-distance flight: hoverflies caught actively migrating through a high mountain pass were subject to four 12-hour flights on a flight-mill with a single day of recovery between each flight. Surprisingly, our initial analysis shows a significant increase in total flight distance and speed along with other flight parameters with each flight bout. Future studies aim to characterise the structural and molecular signatures of flight muscle function that contribute to the enhanced flight performance in this model system.
