Meeting Abstract
The flight muscles of birds undergo physiological changes during migratory seasons. These alterations include increased aerobic and fatty acid oxidation capacity, which help sustain the high-intensity endurance exercise needed for long migratory flights. The degree and full coordination to which birds prepare for migratory season and flight is unknown. We used RNAseq to study flight muscle changes occurring in preparation for and during migratory flight. We sampled flight muscles from captive yellow-rumped warblers (Steophaga coronata) during the fall migratory period at rest, after a 4 h flight in a wind tunnel, and during the winter non-migratory period at rest. Maximum enzyme activity of carnitine palmitoyl transferase, lactate dehydrogenase, citrate synthase and 3-hydroxyacyl CoA dehydrogenase were measured on 5 birds from each condition. The mRNA of 3 birds per condition was sequenced using Illumina HiSeq technology. Trinity was used for the de novo transcriptome assembly, generating 68577 unique transcripts. Differential gene expression analysis will be performed using edgeR and ALDEX to examine changes in KEGG pathways and gene ontologies. Preliminary results from metabolic enzymes activities revealed higher aerobic and oxidative capacity in migratory conditioned birds. No effect of flight was found on enzyme activity, suggesting that birds increase aerobic and oxidative capacity during migration, which is maintained during flight. The results from differential gene expression will be presented and discussed in relation to preparation for and maintenance of endurance migratory flights.
