ABSTRACT
italic>Gentiana section Cruciata (Gentianaceae) is a medicinally important section of herbs, including Chinese traditional medicine Gentianae Macrophyllae Radix and Tibetan herb Jieji. Here, we assess the taxonomic significance using mtDNA nad1/b-c and nad5/d-e sequence data. A total of 144 nad1/b-c and nad5/d-e sequences from 11 species within Gentianaceae were obtained, including 138 sequences from 10 species within Gentiana section Cruciata and 6 sequences from Halenia elliptica (outgroup). The results showed that mtDNA nad1/b-c has species- level resolution within the section of Cruciata, i.e. the variable in the position 45 “C” could be used as a stable marker locus to distinguish G. robusta from other taxa; the variable in the position 352 and 353 “GA” could distinguish G. crassicaulis and G. tibetica from other taxa within the section. Intraspecies genotype variability was detected in nad1/b-c sequences of G. officinalis and G. siphonantha, respectively. These genotypes could be used as potential DNA barcode. In addition, intraspecies genotype variability was detected in nad5/d-e sequences of G. macrophylla, G. officinalis and G. siphonantha, respectively. Based on the stable marker locus, a species-specific PCR protocol was developed using the primer PF to identifying G. robusta in the section. This study could expand the understanding of the diversity of mtDNA nad1/b-c and nad5/d-e in the genus Gentiana, and provide the essence for the species identification within Gentiana section Cruciata.
ABSTRACT
Objective To in silico clone the NAD1 gene of three common parasites and analyze their bioinformatics,so as to lay the foundation for further research on the NAD gene. Methods By using the in silico cloning method,the full length cDNA (s)of NAD 1 genes of Clonorchis sinensis,Ascaris lumbricoides and Schistosoma japonicum were got,then their physical and chemical properties,compositions of amino acids,subcellular localizations,binary and ternary structures were contrastively an-alyzed.Results The three kinds of NAD1 proteins were similar in the relative molecular weight,subcellular localization,and physical and chemical properties.The NAD1 proteins were highly similar in binary and ternary structures of A.lumbricoides and S.japonicum.The phylogenetic analysis showed that C.sinensis,A.lumbricoides and S.japonicum belonged to the different evolu-tionary branches with a certain of genetic distance. Conclusion The three NAD1 genes got from C.sinensis,A.lumbricoides and S.japonicum by in silico cloning belong to the same gene of different species,which can be widely used in the researches of heritable variation of parasites.
ABSTRACT
Objective To understand the genotypes and nucleotide polymorphisms of Echinococcus granulosus metacestode from humans and sheep in Tianjun region,Qinghai Province. Methods The specific primers were designed according to the cox1 and nad1 genes of E.granulosus mitochondrial genome sequences accessed by GenBank.The primers were used to detect the cyst samples from 16 sheep and 2 humans infected with E.granulosus in Tianjun region of Qinghai Province by PCR,then the PCR amplification products were sequenced,the genotypes and nucleotide polymorphisms of the cox1 and nad1 genes were analyzed.Results The 18 isolated samples all belonged to E.granulosus G1 genotype.Among all the isolates,9 haplotypes ex-isted in the cox1 gene with 16 nucleotide mutation sites,and there were 0 to 5 nucleotide differences with the highest variation rate of 0.31%,whereas 7 haplotypes occurred with 15 nucleotide mutation sites,and there were 1 to 8 nucleotide differences with the highest variation rate of 0.89% for the nad1 gene.Conclusions The epidemic genotype of E.granulosus is G1 in hu-mans and sheep in Tianjun region of Qinghai Province,and the nucleotide polymorphisms of the cox1 gene were more abundant than those of the nad1 gene,and the resolution of the nucleotide polymorphisms of cox1 gene is higher than that of the nad1 gene used in E.granulosus isolates.