Cloning of Gaoyou Duck's NPY Gene and its Adaptive Evolution Test

The primers were designed according to the NPY gene sequences of mammals or duck's congeneric species,then cDNA sequence of NPY gene was cloned from total RNA of tissues in Gaoyou Duck by RT-PCR.Homology and evolution correlation of NPY genes among different species were analyzed by biology infomatic method.PAML4b were used to test the selective pressure of NPY gene.Sequence comparison analysis indicated that the cloned Gaoyou Duck NPY gene cDNA was 300bp in length.The alignment of Gaouyou Duck NPY gene cDNA sequence with those of congeneric species,mammals and fishes showed that the sequence similaries were respectively 92%~96%,77%~84% and 33%~39%.Avians,mammals and fishes were independent in the cladogram topological structure,which was consistent their evolutionary histories.The selection test showed that mammal,s NPY gene had suffered positive selection pressure,however,avian and fish NPY gene had suffered stronger purifying selection.The results could aid to trace the route of NPY gene evolution and knowledge of its structure and function variations.It also laid a foundation for the further study on relations between NPY gene with reproduction performance of Ducks.