==== Front Mitochondrial DNA B Resour Mitochondrial DNA B Resour Mitochondrial DNA. Part B, Resources 2380-2359 Taylor & Francis 10.1080/23802359.2019.1677525 1677525 Version of RecordResearch Article Mitogenome Announcement The complete mitochondrial genome of heartbreak grass Gelsemium elegans (Gardner & Champ.) Benth. (Gelsemiaceae) Y.-H. Jin et al.Jin Yong-Hui a Wu Jun-Jie a Peng Yong-Qing a Hu Shu-Hang a Yan Hai-Shan a Xiao Fan a Zhou Xuan a Gao Jing a Wang Rui-Hong a Xu Ling a Qi Zhe-Chen ab a Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, China; b Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai, China CONTACT Rui-Hong Wang seemefly77@126.com; Ling Xu lxu@zstu.edu.cn; Zhe-Chen Qi zqi@zstu.edu.cnZhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou310018, Zhejiang, China 23 10 2019 2019 4 2 3721 3722 © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.2019The Author(s)This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.http://creativecommons.org/licenses/by/4.0/Abstract Gelsemium elegans, endemic to southern Asia, is a highly toxic plant with various medicinal functions. The complete mitochondrial genome of G. elegans was sequenced and assembled in this study. The genome is 405,990 bp in length and contains 37 protein-coding genes, 20 tRNA genes, and 3 rRNA genes. The phylogenetic tree based on 15 protein-coding genes common to six mitochondrial genomes in Gentianales support that G. elegans of Gelsemiaceae is sister to Apocynaceae. Keywords Gelsemium elegansmitochondrial genomephylogeneticstoxic plant ==== Body Gelsemium elegans (Gardner & Champ.) Benth., also known as heartbreak grass or ‘Duan Chang Cao’ in Chinese, is a highly poisonous vine in Gelsemiaceae. It is indigenous to south and southeast Asia. Gelsemium extract contains toxic alkaloids such as gelsemine, gelsenicine, gelsevirine, and koumine (Zhang et al. 2015). Intoxication of G. elegans could cause paralysis, asphyxia, convulsions, and even death due to multiple organ failure in severe conditions (Zhou et al. 2017). Previous studies demonstrated that G. elegans had anti-inflammatory, immunomodulating, analgesic, anxiolytic, anti-tumor, and neuropathic pain-relieving properties (Liu et al. 2019). In this study, we report the first complete mitochondrial genome of G. elegans which will provide essential genetic data for further genetic improvement and effective use of this medicinally important species. The leaves of G. elegans were collected from Liuzhou, Guangxi, China (GPS: E109°14'43'', N24°20'40'', Voucher No. ZSTU03201, deposited at Herbarium of Zhejiang University). DNA was extracted from its silica dried leaves using DNA Plantzol Reagent (Invitrogen, Carlsbad, CA). The total genomic sequences were generated using the Illumina HiSeq 2500 platform (Illumina Inc., San Diego, CA). In total, about 9.2 G high-quality clean reads (150 bp PE read length) were generated with adaptors trimmed. Firstly, the chloroplast genome of G. elegans was firstly assembled following Liu et al. (2017, 2018). Then, sequence of G. elegans plastome and a sequence of ATPase subunit 1 (Accession: KF541337) were set as reference in NOVOPlasty (Dierckxsens et al. 2017) for mitochondrion genome de novo assembly. Finally, aligning and annotation were conducted by BLAST, GeSeq (Tillich et al. 2017) and GENEIOUS Prime (Biomatters Ltd., Auckland, New Zealand). The complete mitochondrial genome of G. elegans (Accession: MN388837) has a length of 405,990 bp with a typical circle structure and a GC content of 44.4%. The genome contains 37 protein-coding genes, including ones for NADH dehydrogenase (nad1, 2, 3, 4, 4L, 5, 6, 7, 9), cytochrome c oxidase (cox1, 2, 3), cytochrome c biogenesis (ccmB, C, Fn, Fc), apocytochrome b (cob), ATP synthase (atp1, 4, 8, 9), ribosomal proteins (rpl2, 5, 10 and rps1, 3, 4, 7, 10, 12, 13, 19), succinate dehydrogenase(sdh3, 4), maturase and membrane transporter (mttB and matR). Additionally, the genome also contains 20 tRNA genes coding for 17 amino acids, 3 rRNA genes (rrn5, 18, 26). Fifteen mitochondrial specific protein-coding genes (atp1, atp4, atp8, atp9, ccmB, ccmC, cob, cox2, mttB, nad3, nad4, nad7, rpl5, rps13, rps3) from six species were selected to study the phylogenetic placement of G. elegans in Gentianales. The sequence alignment was conducted by MAFFT v7.3 (Katoh and Standley 2013). The software IQtree (Nguyen et al. 2015) was used to draw the phylogenetic tree with 5000 bootstrap replicates and TVM + F + G4 model. The phylogenetic tree exhibited that G. elegans of Gelsemiaceae was closely related to Apocynaceae in Gentianales (Figure 1). Disclosure statement The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper. Figure 1. The best maximum-likelihood (ML) phylogram inferred from 6 plant mt genomes based on 15 protein-coding genes. Accession numbers are as follows: Asclepias syriaca (KF541337), Rhazya stricta (KJ485850), Salvia miltiorrhiza (KF177345), Pentas lanceolate (KY492150, KY637224, KY637398, KY637630, KY637974, KY638032, KY638090, KY638148, KY638264, KY638495, KY638957, KY639015, KY639073, KY639131, KY639229), and Dunnia sinensis (KY492163, KY637237, KY637411, KY637643, KY637987, KY638045, KY638103, KY638161, KY638277, KY638506, KY638970, KY639028, KY639086, KY639144, KY639242). ==== Refs References Dierckxsens N , Mardulyn P , Smits G 2017 NOVOPlasty: de novo assembly of organelle genomes from whole genome data . Nucl Acids Res . 45 :e18 .28204566 Katoh K , Standley DM 2013 MAFFT Multiple Sequence Alignment Software Version 7: improvements in Performance and Usability . Mol Biol Evol . 30 :772 –780 .23329690 Liu L , Li P , Zhang HW , Worth J 2018 Whole chloroplast genome sequences of the Japanese hemlocks, Tsuga diversifolia and T. Sieboldii, and development of chloroplast microsatellite markers applicable to East Asian Tsuga . J Forest Res-JPN . 23 :318 –323 . Liu L , Li R , Worth JRP , Li X , Li P , Cameron KM , Fu C 2017 The complete chloroplast genome of Chinese Bayberry (Morella rubra, Myricaceae): implications for understanding the evolution of Fagales . Front Plant Sci . 8 :968 .28713393 Liu Y , Tang Q , Cheng P , Zhu M , Zhang H , Liu J , Zuo M , Huang C , Wu C , Sun Z , et al. 2019 Whole-genome sequencing and analysis of the Chinese herbal plant Gelsemium elegans . Acta Pharm Sin B . accessed on August 30th, 2019 Nguyen LT , Schmidt HA , von Haeseler A , Minh BQ 2015 IQ-TREE: a fast and effective stochastic algorithm for estimating maximum-likelihood phylogenies . Mol Biol Evol . 32 :268 –274 .25371430 Tillich M , Lehwark P , Pellizzer T , Ulbricht-Jones ES , Fischer A , Bock R , Greiner S 2017 GeSeq - versatile and accurate annotation of organelle genomes . Nucl Acids Res . 45 :W6 –W11 .28486635 Zhang QP , Wang ZT , Chou GX 2015 Preparative separation of four alkaloids from Gelsemium elegans by high-speed counter-current chromatography . Chin Herb Med . 7 :267 –272 . Zhou Z , Wu L , Zhong Y , Fang X , Liu Y , Chen H , Zhang W 2017 Gelsemium elegans poisoning: a case with 8 months of follow-up and review of the literature . Front Neurol . 8 :204 .28567028