Poster Presentation Society for Molecular Biology and Evolution Conference 2016

Molecular evolution of dietary diversification in birds (#536)

Kai Wang 1 , Yi Wang 1 , Huabin Zhao 1
  1. College of Life Sciences, Wuhan University, Wuhan, HUBEI, China

          Dietary diversification is affected by both sensory perception and nutrient metabolism. We are studying taste receptor genes and digestive enzyme genes to recover the evolutionary history of dietary diversification in birds, which are rich in species and diets. First, we characterized the evolution of avian bitter taste receptor genes (Tas2rs) based on 48 genomes representing all but 3 avian orders. We found that birds generally carry a small repertoire of Tas2rs, and uncovered a positive correlation between the number of putatively functional Tas2rs and the abundance of potential toxins in avian diets. Second, we examined a digestive enzyme gene CHIA, which encodes an enzyme degrading chitin, across the 48 birds as mentioned above. We found that this gene has undergone multiple independent duplication events, driven by positive selection, in most insect-eating birds. Because chitin is abundant in insects, we are testing whether this gene has experienced adaptive functional diversification in insect-eating birds, by measuring enzyme activities of the recombinant enzyme in E.coli. Taken together, we attempt to uncover the genetic evidence in response to dietary changes in birds by examining the evolution of sensory genes and digestive-related genes. Our future work will continue to focus on molecular evolution and ecology in vertebrates, particularly in birds that are iconic in China or the Tibetan Plateau. (Contact Dr. Huabin Zhao by email: