[Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. ...[Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. Combined with ND2 gene sequences of the Anas Linnaeus accessed in GenBank, phylogenetic tree was constructed by Neighbor-joining and maximum parsimony methods. [Result] The ND2 gene sequences of 4 Anas platyrhynchos were identical(1 041 bp in length; the nucleotide contents of A, G, T, and C were 28.91%, 13.35%, 20.75% and 36.98% respectively; A+T content approximated to that of C+G). Sequences of ND2 gene of mallard were same as spotbill duck, and had high homology with others. The phylogenetic trees indicated mallard and spotbilled duck were close in genetic relationship, both shared a haplotype; then Philippine duck, green-winged teal and northern pintail fell into branch ''A". [Conclusion] The domestic duck may be domesticated from mallard and spotbilled duck.展开更多
The nucleotide sequence of shallot yellow stripe virus from onion(SYSV-O)in Shaanxi Province of China was described.It was 10427 nucleotides(nt)in length excluding the poly(A)tail and was predicted to encode a polypro...The nucleotide sequence of shallot yellow stripe virus from onion(SYSV-O)in Shaanxi Province of China was described.It was 10427 nucleotides(nt)in length excluding the poly(A)tail and was predicted to encode a polyprotein of 3340 amino acids(aa)with a calculated molecular weight of 379.7kD.SYSV was most closely related to onion yellow dwarf virus(OYDV)and resembled it in having a much larger P3 protein than other species in the genus.SYSV-O shared 93.2% nt identity to the published sequence of a welsh onion isolate of SYSV(SYSV-ZQ2).The two isolates differed in NIb-CP cleavage site,that of SYSV-O was Q/V but Q/A in SYSV-ZQ2.Nucleotide identity of coat protein genes amongst all SYSV sequences ranged from 87.3%-84.1%.Phylogenetic tree analysis based on the 3’-terminal nucleotide sequences of SYSV isolates confirmed the existence of four distinct groups that were partially related to geographical origin and host plant species.展开更多
基金Supported by National Key Technology R&D program(2006BAD06B06)National Infrastructure of Natural Resources for Science and Technology(2004DKA30460)~~
文摘[Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. Combined with ND2 gene sequences of the Anas Linnaeus accessed in GenBank, phylogenetic tree was constructed by Neighbor-joining and maximum parsimony methods. [Result] The ND2 gene sequences of 4 Anas platyrhynchos were identical(1 041 bp in length; the nucleotide contents of A, G, T, and C were 28.91%, 13.35%, 20.75% and 36.98% respectively; A+T content approximated to that of C+G). Sequences of ND2 gene of mallard were same as spotbill duck, and had high homology with others. The phylogenetic trees indicated mallard and spotbilled duck were close in genetic relationship, both shared a haplotype; then Philippine duck, green-winged teal and northern pintail fell into branch ''A". [Conclusion] The domestic duck may be domesticated from mallard and spotbilled duck.
文摘The nucleotide sequence of shallot yellow stripe virus from onion(SYSV-O)in Shaanxi Province of China was described.It was 10427 nucleotides(nt)in length excluding the poly(A)tail and was predicted to encode a polyprotein of 3340 amino acids(aa)with a calculated molecular weight of 379.7kD.SYSV was most closely related to onion yellow dwarf virus(OYDV)and resembled it in having a much larger P3 protein than other species in the genus.SYSV-O shared 93.2% nt identity to the published sequence of a welsh onion isolate of SYSV(SYSV-ZQ2).The two isolates differed in NIb-CP cleavage site,that of SYSV-O was Q/V but Q/A in SYSV-ZQ2.Nucleotide identity of coat protein genes amongst all SYSV sequences ranged from 87.3%-84.1%.Phylogenetic tree analysis based on the 3’-terminal nucleotide sequences of SYSV isolates confirmed the existence of four distinct groups that were partially related to geographical origin and host plant species.