Jing Li1,2, Liqiang Wang3, Qing Du4,5,6, Haimei Chen1, Mei Jiang1,7, Zhuoer Chen1,2, Chuanbei Jiang8, Haidong Gao8, Bin Wang9, Chang Liu10. 1. Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, No. 151, Malianwa North Road, Hai Dian District, Beijing, 100193, People's Republic of China. 2. Xiangnan University, No. 889, Chenzhou dadao, Chenzhou City, Hunan Province, 423000, People's Republic of China. 3. College of Pharmacy, Heze University, No.2269, University Road, Mudan District, Heze City, Shandong Province, 274015, People's Republic of China. 4. Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, No. 151, Malianwa North Road, Hai Dian District, Beijing, 100193, People's Republic of China. 171765300@qq.com. 5. College of Pharmacy, Key Laboratory of Medicinal Plant Resources of Qinghai-Tibetan Plateau in Qinghai Province, Qinghai Minzu University, No.3, Bayi Mid-road, Chengdong District, Xining City, Qinghai Province, 810007, People's Republic of China. 171765300@qq.com. 6. Fresh Sky-Right (Beijing) International Science and Technology Co., Ltd, No.59, Banjing Road, Haidian District, Beijing, 100097, People's Republic of China. 171765300@qq.com. 7. School of Pharmaceutical Sciences, Qilu University of Technology (Shandong Academy of Sciences), No. 3501, University Road, Changqing District, Jinan City, Shandong Province, 250399, People's Republic of China. 8. Genepioneer Biotechnologies Inc, No. 9, Weidi Road, Qixia District, Nanjing City, Jiangsu Province, 210000, People's Republic of China. 9. Xiangnan University, No. 889, Chenzhou dadao, Chenzhou City, Hunan Province, 423000, People's Republic of China. beinwang@126.com. 10. Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, No. 151, Malianwa North Road, Hai Dian District, Beijing, 100193, People's Republic of China. cliu6688@implad.ac.cn.
Abstract
MAIN CONCLUSION: The complete chloroplast genome of Swertia kouitchensis has been sequenced and assembled, compared with that of S. bimaculata to determine the evolutionary relationships among species of the Swertia in the Gentianaceae family. Swertia kouitchensis and S. bimaculata are from the Gentianaceae family. The complete chloroplast genome of S. kouitchensis was newly assembled, annotated, and analyzed by Illumina Hiseq 2500 platform. The chloroplast genomes of the two species encoded a total of 133, 134 genes, which included 88-89 protein-coding genes, 37 transfer RNA (tRNA) genes, and 8 ribosomal RNA genes. One intron was contained in each of the eight protein-coding genes and eight tRNA-coding genes, whereas two introns were found in two genes (ycf3 and clpP). The most abundant codon of the two species was for isoleucine, and the least abundant codon was for cysteine. The number of microsatellite repeat sequences was twenty-eight and thirty-two identified in the chloroplast genomes of S. kouitchensis and S. bimaculata, respectively. A total of 1127 repeat sequences were identified in all the 23 Swertia chloroplast genomes, and they fell into four categories. Furthermore, five divergence hotspot regions can be applied to discriminate these 23 Swertia species through genomes comparison. One pair of genus-specific DNA barcodes primer has been accurately identified. Therefore, the diverse regions cloned by a specific primer may become an effective and powerful molecular marker for the identification of Swertia genus. Moreover, four genes (ccsA, ndhK, rpoC1, and rps12) were positive selective pressure. The phylogenetic tree showed that the 23 Swertia species were clustered into a large clade including four evident subbranches, whereas the two species of S. kouitchensis and S. bimaculata were separately clustered into the diverse but correlated species group.
MAIN CONCLUSION: The complete chloroplast genome of Swertia kouitchensis has been sequenced and assembled, compared with that of S. bimaculata to determine the evolutionary relationships among species of the Swertia in the Gentianaceae family. Swertia kouitchensis and S. bimaculata are from the Gentianaceae family. The complete chloroplast genome of S. kouitchensis was newly assembled, annotated, and analyzed by Illumina Hiseq 2500 platform. The chloroplast genomes of the two species encoded a total of 133, 134 genes, which included 88-89 protein-coding genes, 37 transfer RNA (tRNA) genes, and 8 ribosomal RNA genes. One intron was contained in each of the eight protein-coding genes and eight tRNA-coding genes, whereas two introns were found in two genes (ycf3 and clpP). The most abundant codon of the two species was for isoleucine, and the least abundant codon was for cysteine. The number of microsatellite repeat sequences was twenty-eight and thirty-two identified in the chloroplast genomes of S. kouitchensis and S. bimaculata, respectively. A total of 1127 repeat sequences were identified in all the 23 Swertia chloroplast genomes, and they fell into four categories. Furthermore, five divergence hotspot regions can be applied to discriminate these 23 Swertia species through genomes comparison. One pair of genus-specific DNA barcodes primer has been accurately identified. Therefore, the diverse regions cloned by a specific primer may become an effective and powerful molecular marker for the identification of Swertia genus. Moreover, four genes (ccsA, ndhK, rpoC1, and rps12) were positive selective pressure. The phylogenetic tree showed that the 23 Swertia species were clustered into a large clade including four evident subbranches, whereas the two species of S. kouitchensis and S. bimaculata were separately clustered into the diverse but correlated species group.
Authors: Richard Cronn; Aaron Liston; Matthew Parks; David S Gernandt; Rongkun Shen; Todd Mockler Journal: Nucleic Acids Res Date: 2008-08-27 Impact factor: 16.971