Evolutionary Study On Vitamin D Binding Protein Gene Of Chiropterans

Vitamin D(VD)is an essential nutrition for mammals.The function of VD not only maintains the balance of calcium and phosphorus but also play a more direct role in innate immunity and inflammatory.Lack of VD will lead to many serious illnesses,like rickets,chondropathy,etc.Vitamin D binding protein(VDBP)is encoded by GC gene.VDBP is crucial for VD metabolic system as bound and transported various forms of vitamin D and its metabolites in the circulatory system.Being nocturnal and strong immune system,chiropterans VD metabolic system is worth concerned.Frugivorous Pteropodidae bats can endogenic VD from photo-biosynthetic though they have no access dietary sources of vitamin D.Insectivorous bats are nocturnal and roost in the dark cave,which means they can only ingest VD in the diet.We hypothesized that VD metabolic system of bats is heavily influenced by dietary habits.Therefore,molecular evolutionary research is done for bats' VDBP gene in this thesis.We found VDBP amino acids sequences can reunited bats as dietary habits,which is conflicting with the species phylogeny.Particular amino acid sites of this gene were found which associated with dietary habits.Several models analysis from PAML results indicated that variance was found in bats of different dietary.The ?fluctuation is correlative with dietary using sliding window analyses.VDBP gene is higher expression in frugivorous bats than insectivorous bats.Results indicated possible revealed adaptive evolution in bats' VDBP gene because of different dietary habits,which caused conflict between the gene tree and bats' species phylogeny.To some extent,our results extended the knowledge of bats dietary habits adaptive evolution and revealed the complexity of bats VD metabolic system.