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Silvério R. Mauad AV, Vieira LDN, Antônio de Baura V, Balsanelli E, Maltempi de Souza E, Chase MW, de Camargo Smidt E. Plastid phylogenomics of Pleurothallidinae (Orchidaceae): Conservative plastomes, new variable markers, and comparative analyses of plastid, nuclear, and mitochondrial data. PLoS One 2021; 16:e0256126. [PMID: 34449781 PMCID: PMC8396723 DOI: 10.1371/journal.pone.0256126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 07/29/2021] [Indexed: 11/19/2022] Open
Abstract
We present the first comparative plastome study of Pleurothallidinae with analyses of structural and molecular characteristics and identification of the ten most-variable regions to be incorporated in future phylogenetic studies. We sequenced complete plastomes of eight species in the subtribe and compared phylogenetic results of these to parallel analyses of their nuclear ribosomal DNA operon (26S, 18S, and 5.8S plus associated spacers) and partial mitochondrial genome sequences (29–38 genes and partial introns). These plastomes have the typical quadripartite structure for which gene content is similar to those of other orchids, with variation only in the composition of the ndh genes. The independent loss of ndh genes had an impact on which genes border the inverted repeats and thus the size of the small single-copy region, leading to variation in overall plastome length. Analyses of 68 coding sequences indicated the same pattern of codon usage as in other orchids, and 13 protein-coding genes under positive selection were detected. Also, we identified 62 polymorphic microsatellite loci and ten highly variable regions, for which we designed primers. Phylogenomic analyses showed that the top ten mutational hotspots represent well the phylogenetic relationships found with whole plastome sequences. However, strongly supported incongruence was observed among plastid, nuclear ribosomal DNA operon, and mitochondrial DNA trees, indicating possible occurrence of incomplete lineage sorting and/or introgressive hybridization. Despite the incongruence, the mtDNA tree retrieved some clades found in other analyses. These results, together with performance in recent studies, support a future role for mitochondrial markers in Pleurothallidinae phylogenetics.
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Affiliation(s)
| | | | - Valter Antônio de Baura
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Eduardo Balsanelli
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Emanuel Maltempi de Souza
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Mark W. Chase
- Royal Botanic Gardens, Kew, Richmond, Surrey, United Kingdom
- Department of Environment and Agriculture, Curtin University, Perth, Western Australia, Australia
| | - Eric de Camargo Smidt
- Departamento de Botânica, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
- * E-mail: (AVSRM); (ECS)
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Santos da Silva R, Roland Clement C, Balsanelli E, de Baura VA, Maltempi de Souza E, Pacheco de Freitas Fraga H, do Nascimento Vieira L. The plastome sequence of Bactris gasipaes and evolutionary analysis in tribe Cocoseae (Arecaceae). PLoS One 2021; 16:e0256373. [PMID: 34428237 PMCID: PMC8384209 DOI: 10.1371/journal.pone.0256373] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 08/04/2021] [Indexed: 11/18/2022] Open
Abstract
The family Arecaceae is distributed throughout tropical and subtropical regions of the world. Among the five subfamilies, Arecoideae is the most species-rich and still contains some ambiguous inter-generic relationships, such as those within subtribes Attaleinae and Bactridineae. The hypervariable regions of plastid genomes (plastomes) are interesting tools to clarify unresolved phylogenetic relationships. We sequenced and characterized the plastome of Bactris gasipaes (Bactridinae) and compared it with eight species from the three Cocoseae sub-tribes (Attaleinae, Bactridinae, and Elaeidinae) to perform comparative analysis and to identify hypervariable regions. The Bactris gasipaes plastome has 156,646 bp, with 113 unique genes. Among them, four genes have an alternative start codon (cemA, rps19, rpl2, and ndhD). Plastomes are highly conserved within tribe Cocoseae: 97.3% identity, length variation of ~2 kb, and a single ~4.5 kb inversion in Astrocaryum plastomes. The LSC/IR and IR/SSC junctions vary among the subtribes: in Bactridinae and Elaeidinae the rps19 gene is completely contained in the IR region; in the subtribe Attaleinae the rps19 gene is only partially contained in the IRs. The hypervariable regions selected according to sequence variation (SV%) and frequency of parsimony informative sites (PIS%) revealed plastome regions with great potential for molecular analysis. The ten regions with greatest SV% showed higher variation than the plastid molecular markers commonly used for phylogenetic analysis in palms. The phylogenetic trees based on the plastomes and the hypervariable regions (SV%) datasets had well-resolved relationships, with consistent topologies within tribe Cocoseae, and confirm the monophyly of the subtribes Bactridinae and Attaleinae.
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Affiliation(s)
| | - Charles Roland Clement
- Coordenação de Tecnologia e Inovação, Instituto Nacional de Pesquisas da Amazônia, Manaus, AM, Brazil
| | - Eduardo Balsanelli
- Departamento de Bioquímica e Biologia Molecular, Núcleo de Fixação Biológica de Nitrogênio, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
- Departamento de Bioquímica e Biologia Molecular, GoGenetic, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Valter Antonio de Baura
- Departamento de Bioquímica e Biologia Molecular, Núcleo de Fixação Biológica de Nitrogênio, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Emanuel Maltempi de Souza
- Departamento de Bioquímica e Biologia Molecular, Núcleo de Fixação Biológica de Nitrogênio, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
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Sakaguchi S, Asaoka Y, Takahashi D, Isagi Y, Imai R, Nagano AJ, Qiu YX, Li P, Lu R, Setoguchi H. Inferring historical survivals of climate relicts: the effects of climate changes, geography, and population-specific factors on herbaceous hydrangeas. Heredity (Edinb) 2021; 126:615-629. [PMID: 33510468 PMCID: PMC8115046 DOI: 10.1038/s41437-020-00396-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 11/25/2020] [Accepted: 12/08/2020] [Indexed: 01/29/2023] Open
Abstract
Climate relicts hold considerable importance because they have resulted from numerous historical changes. However, there are major interspecific variations among the ways by which they survived climate changes. Therefore, investigating the factors and timing that affected population demographics can expand our understanding of how climate relicts responded to historical environmental changes. Here, we examined herbaceous hydrangeas of genus Deinanthe in East Asia, which show limited distributions and a remarkable disjunction between Japan and central China. Chloroplast genome and restriction site-associated DNA sequencing revealed that speciation event occurred in the late Miocene (ca. 7-9 Mya) in response to global climate change. Two lineages apparently remained not branched until the middle Quaternary, and afterwards started to diverge to regional population groups. The narrow endemic species in central China showed lower genetic diversity (He = 0.082), as its population size rapidly decreased during the Holocene due to isolation in montane refugia. Insular populations in the three Japanese islands (He = 0.137-0.160) showed a genetic structure that was inconsistent with sea barriers, indicating that it was shaped in the glacial period when its range retreated to coastal refugia on the exposed sea floor. Demographic modelling by stairway-plot analysis reconstructed variable responses of Japanese populations: some experienced glacial bottlenecks in refugial isolation, while post-glacial range expansion seemingly exerted founder effects on other populations. Overall, this study demonstrated the involvement of not just one, but multiple factors, such as the interplay between climate changes, geography, and other population-specific factors, that determine the demographics of climate relicts.
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Affiliation(s)
- Shota Sakaguchi
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan.
| | - Yui Asaoka
- Faculty of Integrated Human Studies, Kyoto University, Kyoto, 606-8501, Japan
- Primate Research Institute, Kyoto University, Inuyama, Aichi, 484-8506, Japan
| | - Daiki Takahashi
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan
| | - Yuji Isagi
- Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Ryosuke Imai
- Iriomote Station, Tropical Biosphere Research Centre, University of the Ryukyus, Okinawa, 907-1541, Japan
| | - Atsushi J Nagano
- Faculty of Agriculture, Ryukoku University, Shiga, 520-2194, Japan
| | - Ying-Xiong Qiu
- College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Pan Li
- College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Ruisen Lu
- College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Hiroaki Setoguchi
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan
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Sharpe RM, Williamson-Benavides B, Edwards GE, Dhingra A. Methods of analysis of chloroplast genomes of C 3, Kranz type C 4 and Single Cell C 4 photosynthetic members of Chenopodiaceae. PLANT METHODS 2020; 16:119. [PMID: 32874195 PMCID: PMC7457496 DOI: 10.1186/s13007-020-00662-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Chloroplast genome information is critical to understanding forms of photosynthesis in the plant kingdom. During the evolutionary process, plants have developed different photosynthetic strategies that are accompanied by complementary biochemical and anatomical features. Members of family Chenopodiaceae have species with C3 photosynthesis, and variations of C4 photosynthesis in which photorespiration is reduced by concentrating CO2 around Rubisco through dual coordinated functioning of dimorphic chloroplasts. Among dicots, the family has the largest number of C4 species, and greatest structural and biochemical diversity in forms of C4 including the canonical dual-cell Kranz anatomy, and the recently identified single cell C4 with the presence of dimorphic chloroplasts separated by a vacuole. This is the first comparative analysis of chloroplast genomes in species representative of photosynthetic types in the family. RESULTS Methodology with high throughput sequencing complemented with Sanger sequencing of selected loci provided high quality and complete chloroplast genomes of seven species in the family and one species in the closely related Amaranthaceae family, representing C3, Kranz type C4 and single cell C4 (SSC4) photosynthesis six of the eight chloroplast genomes are new, while two are improved versions of previously published genomes. The depth of coverage obtained using high-throughput sequencing complemented with targeted resequencing of certain loci enabled superior resolution of the border junctions, directionality and repeat region sequences. Comparison of the chloroplast genomes with previously sequenced plastid genomes revealed similar genome organization, gene order and content with a few revisions. High-quality complete chloroplast genome sequences resulted in correcting the orientation the LSC region of the published Bienertia sinuspersici chloroplast genome, identification of stop codons in the rpl23 gene in B. sinuspersici and B. cycloptera, and identifying an instance of IR expansion in the Haloxylon ammodendron inverted repeat sequence. The rare observation of a mitochondria-to-chloroplast inter-organellar gene transfer event was identified in family Chenopodiaceae. CONCLUSIONS This study reports complete chloroplast genomes from seven Chenopodiaceae and one Amaranthaceae species. The depth of coverage obtained using high-throughput sequencing complemented with targeted resequencing of certain loci enabled superior resolution of the border junctions, directionality, and repeat region sequences. Therefore, the use of high throughput and Sanger sequencing, in a hybrid method, reaffirms to be rapid, efficient, and reliable for chloroplast genome sequencing.
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Affiliation(s)
- Richard M. Sharpe
- Department of Horticulture, Washington State University, Pullman, WA 99164 USA
| | - Bruce Williamson-Benavides
- Department of Horticulture, Washington State University, Pullman, WA 99164 USA
- Molecular Plants Sciences, Washington State University, Pullman, WA 99164 USA
| | - Gerald E. Edwards
- Molecular Plants Sciences, Washington State University, Pullman, WA 99164 USA
- School of Biological Sciences, Washington State University, Pullman, WA 99164 USA
| | - Amit Dhingra
- Department of Horticulture, Washington State University, Pullman, WA 99164 USA
- Molecular Plants Sciences, Washington State University, Pullman, WA 99164 USA
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Zavala-Páez M, Vieira LDN, de Baura VA, Balsanelli E, de Souza EM, Cevallos MC, Chase MW, Smidt EDC. Comparative Plastid Genomics of Neotropical Bulbophyllum (Orchidaceae; Epidendroideae). FRONTIERS IN PLANT SCIENCE 2020; 11:799. [PMID: 32719690 PMCID: PMC7347972 DOI: 10.3389/fpls.2020.00799] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/19/2020] [Indexed: 05/23/2023]
Abstract
Pantropical Bulbophyllum, with ∼2,200 species, is one of the largest genera in Orchidaceae. Although phylogenetics and taxonomy of the ∼60 American species in the genus are generally well understood, some species complexes need more study to clearly delimit their component species and provide information about their evolutionary history. Previous research has suggested that the plastid genome includes phylogenetic markers capable of providing resolution at low taxonomic levels, and thus it could be an effective tool if these divergent regions can be identified. In this study, we sequenced the complete plastid genome of eight Bulbophyllum species, representing five of six Neotropical taxonomic sections. All plastomes conserve the typical quadripartite structure, and, although the general structure of plastid genomes is conserved, differences in ndh-gene composition and total length were detected. Total length was determined by contraction and expansion of the small single-copy region, a result of an independent loss of the seven ndh genes. Selection analyses indicated that protein-coding genes were generally well conserved, but in four genes, we identified 95 putative sites under positive selection. Furthermore, a total of 54 polymorphic simple sequence repeats were identified, for which we developed amplification primers. In addition, we propose 10 regions with potential to improve phylogenetic analyses of Neotropical Bulbophyllum species.
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Affiliation(s)
| | | | - Valter Antônio de Baura
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, Brazil
| | - Eduardo Balsanelli
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, Brazil
| | | | - Marco Cerna Cevallos
- Grupo de Investigación Nunkui Wakan, Universidad Politécnica Salesiana, Quito, Ecuador
| | - Mark W. Chase
- Royal Botanic Gardens, Kew, Richmond, United Kingdom
- Department of Environment and Agriculture, Curtin University, Perth, WA, Australia
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Li H, Ma D, Li J, Wei M, Zheng H, Zhu X. Illumina sequencing of complete chloroplast genome of Avicennia marina, a pioneer mangrove species. MITOCHONDRIAL DNA PART B-RESOURCES 2020; 5:2131-2132. [PMID: 33366945 PMCID: PMC7510616 DOI: 10.1080/23802359.2020.1768927] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 05/09/2020] [Indexed: 10/25/2022]
Abstract
Mangrove tree Avicenna marina has great ecological significance in maintaining coastal ecosystem, but its unique potential for gene functions and genetic diversity underlying ecological adaptation remains investigation. In this study, the chloroplast genome of A. marina was first characterized by sequencing chloroplast DNA with Illumina technology. The A. marina genome was 147,909 bp in size with a typical quadripartite structure, which was deposited in GenBank under the accession number MT108381.
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Affiliation(s)
- Huan Li
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Dongna Ma
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Jing Li
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Mingyue Wei
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Hailei Zheng
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Xueyi Zhu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, China
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Smidt EDC, Páez MZ, Vieira LDN, Viruel J, de Baura VA, Balsanelli E, de Souza EM, Chase MW. Characterization of sequence variability hotspots in Cranichideae plastomes (Orchidaceae, Orchidoideae). PLoS One 2020; 15:e0227991. [PMID: 31990943 PMCID: PMC6986716 DOI: 10.1371/journal.pone.0227991] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/03/2020] [Indexed: 11/26/2022] Open
Abstract
This study reports complete plastome sequences for six species of Neotropical Cranichideae and focuses on identification of the most variable regions (hotspots) in this group of orchids. These structure of these six plastomes is relatively conserved, exhibiting lengths ranging between 142,599 to 154,562 bp with 36.7% GC on average and exhibiting typical quadripartite arrangement (LSC, SSC and two IRs). Variation detected in the LSC/IR and SSC/IR junctions is explained by the loss of ndhF and ycf1 length variation. For the two genera of epiphytic clade in Spiranthinae, almost whole sets of the ndh-gene family were missing. Eight mutation hotspots were identified based on nucleotide diversity, sequence variability and parsimony-informative sites. Three of them (rps16-trnQ, trnT-trnL, rpl32-trnL) seem to be universal hotspots in the family, and the other five (trnG-trnR, trnR-atpA, trnP-psaJ, rpl32-infA, and rps15-ycf1) are described for the first time as orchid molecular hotspots. These regions have much more variation than all those used previously in phylogenetics of the group and offer useful plastid markers for phylogenetic, barcoding and population genetic studies. The use of whole plastomes or exclusive no-gap matrices also positioned with high support the holomycotrophic Rhizanthella among Orchidoideae plastomes in model-based analyses, showing the utility of plastomes for phylogenetic placement of this unusual genus.
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Affiliation(s)
| | - Michelle Zavala Páez
- Departamento de Botânica, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | | | - Juan Viruel
- Royal Botanic Gardens, Kew, Richmond, Surrey, England, United Kingdom
| | - Valter Antônio de Baura
- Departamento de Bioquímica, Universidade Federal do Paraná, Núcleo de Fixação Biológica de Nitrogênio, Curitiba, Paraná, Brazil
| | - Eduardo Balsanelli
- Departamento de Bioquímica, Universidade Federal do Paraná, Núcleo de Fixação Biológica de Nitrogênio, Curitiba, Paraná, Brazil
| | - Emanuel Maltempi de Souza
- Departamento de Bioquímica, Universidade Federal do Paraná, Núcleo de Fixação Biológica de Nitrogênio, Curitiba, Paraná, Brazil
| | - Mark W. Chase
- Royal Botanic Gardens, Kew, Richmond, Surrey, England, United Kingdom
- Department of Environment and Agriculture, Curtin University, Perth, Western Australia, Australia
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Complete Chloroplast Genomes and Comparative Analysis of Sequences Evolution among Seven Aristolochia (Aristolochiaceae) Medicinal Species. Int J Mol Sci 2019; 20:ijms20051045. [PMID: 30823362 PMCID: PMC6429227 DOI: 10.3390/ijms20051045] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/14/2019] [Accepted: 02/21/2019] [Indexed: 11/16/2022] Open
Abstract
Aristolochiaceae, comprising about 600 species, is a unique plant family containing aristolochic acids (AAs). In this study, we sequenced seven species of Aristolochia, and retrieved eleven chloroplast (cp) genomes published for comparative genomics analysis and phylogenetic constructions. The results show that the cp genomes had a typical quadripartite structure with conserved genome arrangement and moderate divergence. The cp genomes range from 159,308 bp to 160,520 bp in length and have a similar GC content of 38.5%–38.9%. A total number of 113 genes were identified, including 79 protein-coding genes, 30 tRNAs and four rRNAs. Although genomic structure and size were highly conserved, the IR-SC boundary regions were variable between these seven cp genomes. The trnH-GUG genes, are one of major differences between the plastomes of the two subgenera Siphisia and Aristolochia. We analyzed the features of nucleotide substitutions, distribution of repeat sequences and simple sequences repeats (SSRs), positive selections in the cp genomes, and identified 16 hotspot regions for genomes divergence that could be utilized as potential markers for phylogeny reconstruction. Phylogenetic relationships of the family Aristolochiaceae inferred from the 18 cp genome sequences were consistent and robust, using maximum parsimony (MP), maximum likelihood (ML), and Bayesian analysis (BI) methods.
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Zhao R, Xing YP, Yin HB, Kang TG. Complete sequence of the chloroplast genome of Asarum heterotropoides (Aristolochiales: Asarum L.). Mitochondrial DNA B Resour 2019. [DOI: 10.1080/23802359.2019.1598783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Affiliation(s)
- Rong Zhao
- School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian, China
| | - Yan-Ping Xing
- School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian, China
| | - Hai-Bo Yin
- School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian, China
| | - Ting-Guo Kang
- School of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian, China
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Comparative assessment shows the reliability of chloroplast genome assembly using RNA-seq. Sci Rep 2018; 8:17404. [PMID: 30479362 PMCID: PMC6258696 DOI: 10.1038/s41598-018-35654-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 11/09/2018] [Indexed: 11/08/2022] Open
Abstract
Chloroplast genomes (cp genomes) are widely used in comparative genomics, population genetics, and phylogenetic studies. Obtaining chloroplast genomes from RNA-Seq data seems feasible due to the almost full transcription of cpDNA. However, the reliability of chloroplast genomes assembled from RNA-Seq instead of genomic DNA libraries remains to be thoroughly verified. In this study, we assembled chloroplast genomes for three Erysimum (Brassicaceae) species from three RNA-Seq replicas and from one genomic library of each species, using a streamlined bioinformatics protocol. We compared these assembled genomes, confirming that assembled cp genomes from RNA-Seq data were highly similar to each other and to those from genomic libraries in terms of overall structure, size, and composition. Although post-transcriptional modifications, such as RNA-editing, may introduce variations in the RNA-seq data, the assembly of cp genomes from RNA-seq appeared to be reliable. Moreover, RNA-Seq assembly was less sensitive to sources of error such as the recovery of nuclear plastid DNAs (NUPTs). Although some precautions should be taken when producing reference genomes in non-model plants, we conclude that assembling cp genomes from RNA-Seq data is a fast, accurate, and reliable strategy.
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