Chloroplast Genome Evolution in Four Montane Zingiberaceae Taxa in China

Chloroplasts are critical to plant survival and adaptive evolution. The comparison of chloroplast genomes could provide insight into the adaptive evolution of closely related species. To identify potential adaptive evolution in the chloroplast genomes of four montane Zingiberaceae taxa (Cautleya, Roscoea, Rhynchanthus, and Pommereschea) that inhabit distinct habitats in the mountains of Yunnan, China, the nucleotide sequences of 13 complete chloroplast genomes, including five newly sequenced species, were characterized and compared. The five newly sequenced chloroplast genomes (162,878–163,831 bp) possessed typical quadripartite structures, which included a large single copy (LSC) region, a small single copy (SSC) region, and a pair of inverted repeat regions (IRa and IRb), and even though the structure was highly conserved among the 13 taxa, one of the rps19 genes was absent in Cautleya, possibly due to expansion of the LSC region. Positive selection of rpoA and ycf2 suggests that these montane species have experienced adaptive evolution to habitats with different sunlight intensities and that adaptation related to the chloroplast genome has played an important role in the evolution of Zingiberaceae taxa.

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Stable and widespread structural heteroplasmy in chloroplast genomes revealed by a new long-read quantification method

10.1101/692798 ◽

2019 ◽

Author(s):

Weiwen Wang ◽

Robert Lanfear

Keyword(s):

Chloroplast Genome ◽

Single Copy ◽

Land Plant ◽

Inverted Repeats ◽

Equal Frequency ◽

Large Single Copy ◽

Chloroplast Genomes ◽

Long Read ◽

Small Single Copy ◽

Large Single Copy Region

AbstractThe chloroplast genome usually has a quadripartite structure consisting of a large single copy region and a small single copy region separated by two long inverted repeats. It has been known for some time that a single cell may contain at least two structural haplotypes of this structure, which differ in the relative orientation of the single copy regions. However, the methods required to detect and measure the abundance of the structural haplotypes are labour-intensive, and this phenomenon remains understudied. Here we develop a new method, Cp-hap, to detect all possible structural haplotypes of chloroplast genomes of quadripartite structure using long-read sequencing data. We use this method to conduct a systematic analysis and quantification of chloroplast structural haplotypes in 61 land plant species across 19 orders of Angiosperms, Gymnosperms and Pteridophytes. Our results show that there are two chloroplast structural haplotypes which occur with equal frequency in most land plant individuals. Nevertheless, species whose chloroplast genomes lack inverted repeats or have short inverted repeats have just a single structural haplotype. We also show that the relative abundance of the two structural haplotypes remains constant across multiple samples from a single individual plant, suggesting that the process which maintains equal frequency of the two haplotypes operates rapidly, consistent with the hypothesis that flip-flop recombination mediates chloroplast structural heteroplasmy. Our results suggest that previous claims of differences in chloroplast genome structure between species may need to be revisited.Significance StatementChloroplast genome consists of a large single copy region, a small single copy region, and two inverted repeats. Some decades ago, a discovery showed that there are two types chloroplast genome in some plants, which differ the way that the four regions are put together. However, this phenomenon has been shown in just a small number of species, and many open questions remain. Here, we develop a fast method to measure the chloroplast genome structures, based on long-reads. We show that almost all plants we analysed contain two possible genome structures, while a few plants contain only one structure. Our findings hint at the causes of the phenomenon, and provide a convenient new method with which to make rapid progress.

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Comparative Chloroplast Genomics in Phyllanthaceae Species

Diversity ◽

10.3390/d13090403 ◽

2021 ◽

Vol 13 (9) ◽

pp. 403

Author(s):

Umar Rehman ◽

Nighat Sultana ◽

Abdullah ◽

Abbas Jamal ◽

Maryam Muzaffar ◽

...

Keyword(s):

Chloroplast Genome ◽

De Novo ◽

Single Copy ◽

Protein Coding ◽

Coding Sequences ◽

Tropical Regions ◽

Chloroplast Genomes ◽

The Family ◽

Insight Into ◽

Small Single Copy

Family Phyllanthaceae belongs to the eudicot order Malpighiales, and its species are herbs, shrubs, and trees that are mostly distributed in tropical regions. Here, we elucidate the molecular evolution of the chloroplast genome in Phyllanthaceae and identify the polymorphic loci for phylogenetic inference. We de novo assembled the chloroplast genomes of three Phyllanthaceae species, i.e., Phyllanthus emblica, Flueggea virosa, and Leptopus cordifolius, and compared them with six other previously reported genomes. All species comprised two inverted repeat regions (size range 23,921–27,128 bp) that separated large single-copy (83,627–89,932 bp) and small single-copy (17,424–19,441 bp) regions. Chloroplast genomes contained 111–112 unique genes, including 77–78 protein-coding, 30 tRNAs, and 4 rRNAs. The deletion/pseudogenization of rps16 genes was found in only two species. High variability was seen in the number of oligonucleotide repeats, while guanine-cytosine contents, codon usage, amino acid frequency, simple sequence repeats, synonymous and non-synonymous substitutions, and transition and transversion substitutions were similar. The transition substitutions were higher in coding sequences than in non-coding sequences. Phylogenetic analysis revealed the polyphyletic nature of the genus Phyllanthus. The polymorphic protein-coding genes, including rpl22, ycf1, matK, ndhF, and rps15, were also determined, which may be helpful for reconstructing the high-resolution phylogenetic tree of the family Phyllanthaceae. Overall, the study provides insight into the chloroplast genome evolution in Phyllanthaceae.

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Complete chloroplast genomes of Anthurium huixtlense and Pothos scandens (Pothoideae, Araceae): unique inverted repeat expansion and contraction affect rate of evolution

10.1101/2020.03.11.987859 ◽

2020 ◽

Cited By ~ 2

Author(s):

Abdullah ◽

Claudia L. Henriquez ◽

Furrukh Mehmood ◽

Monica M. Carlsen ◽

Madiha Islam ◽

...

Keyword(s):

Fold Increase ◽

Single Copy ◽

Large Single Copy ◽

Protein Coding ◽

Synonymous Substitutions ◽

Rate Of Evolution ◽

Chloroplast Genomes ◽

Contraction And Expansion ◽

Insight Into ◽

Small Single Copy

AbstractThe subfamily Pothoideae belongs to the ecologically important plant family Araceae. Here, we report the chloroplast genomes of two species of the subfamily Pothoideae: Anthurium huixtlense (163,116 bp) and Pothos scandens (164,719 bp). The chloroplast genome of P. scandens showed unique inverted repeats (IRs) contraction and expansion, which increases the size of the large single copy (102,956) region and decreases the size of the small single-copy (6779 bp) region. This led to duplication of many single-copy genes due to transfer to IR regions from the small single-copy (SSC) region, whereas some duplicate genes became single copy due to transfer to large single-copy regions. The rate of evolution of protein-coding genes was affected by the contraction and expansion of IRs; we found higher mutation rates for genes that exist in single-copy regions as opposed to IRs. We found a 2.3-fold increase of oligonucleotide repeats in P. scandens when compared with A. huixtlense, whereas amino acid frequency and codon usage revealed similarities. We recorded higher transition substitutions than transversion substitutions. The transition/transversion ratio was 2.26 in P. scandens and 2.12 in A. huixtlense. We also found a higher rate of transversion substitutions linked with non-synonymous substitutions than synonymous substitutions. The phylogenetic inference of the limited species showed the monophyly of the Araceae subfamilies. Our study provides insight into the molecular evolution of chloroplast genomes in the subfamily Pothoideae and family Araceae.

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A Circular Chloroplast Genome of Fagus sylvatica Reveals High Conservation between Two Individuals from Germany and One Individual from Poland and an Alternate Direction of the Small Single-Copy Region

Forests ◽

10.3390/f12020180 ◽

2021 ◽

Vol 12 (2) ◽

pp. 180

Author(s):

Bagdevi Mishra ◽

Bartosz Ulaszewski ◽

Sebastian Ploch ◽

Jaroslaw Burczyk ◽

Marco Thines

Keyword(s):

Chloroplast Genome ◽

Fagus Sylvatica ◽

Pollen Dispersal ◽

European Beech ◽

Single Copy ◽

Migration History ◽

Chloroplast Genomes ◽

Long Read ◽

The Individual ◽

Small Single Copy

Chloroplasts are difficult to assemble because of the presence of large inverted repeats. At the same time, correct assemblies are important, as chloroplast loci are frequently used for biogeography and population genetics studies. In an attempt to elucidate the orientation of the single-copy regions and to find suitable loci for chloroplast single nucleotide polymorphism (SNP)-based studies, circular chloroplast sequences for the ultra-centenary reference individual of European Beech (Fagus sylvatica), Bhaga, and an additional Polish individual (named Jamy) was obtained based on hybrid assemblies. The chloroplast genome of Bhaga was 158,458 bp, and that of Jamy was 158,462 bp long. Using long-read mapping on the configuration inferred in this study and the one suggested in a previous study, we found an inverted orientation of the small single-copy region. The chloroplast genome of Bhaga and of the individual from Poland both have only two mismatches as well as three and two indels as compared to the previously published genome, respectively. The low divergence suggests low seed dispersal but high pollen dispersal. However, once chloroplast genomes become available from Pleistocene refugia, where a high degree of variation has been reported, they might prove useful for tracing the migration history of Fagus sylvatica in the Holocene.

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Complete chloroplast genome sequences of Dioscorea: Characterization, genomic resources, and phylogenetic analyses

PeerJ ◽

10.7717/peerj.6032 ◽

2018 ◽

Vol 6 ◽

pp. e6032 ◽

Cited By ~ 12

Author(s):

Zhenyu Zhao ◽

Xin Wang ◽

Yi Yu ◽

Subo Yuan ◽

Dan Jiang ◽

...

Keyword(s):

Chloroplast Genome ◽

Phylogenetic Analyses ◽

Single Copy ◽

Genome Sequences ◽

Complete Chloroplast Genome ◽

Genomic Resources ◽

Chloroplast Genomes ◽

The Family ◽

Small Single Copy

Dioscorea L., the largest genus of the family Dioscoreaceae with over 600 species, is not only an important food but also a medicinal plant. The identification and classification of Dioscorea L. is a rather difficult task. In this study, we sequenced five Dioscorea chloroplast genomes, and analyzed with four other chloroplast genomes of Dioscorea species from GenBank. The Dioscorea chloroplast genomes displayed the typical quadripartite structure of angiosperms, which consisted of a pair of inverted repeats separated by a large single-copy region, and a small single-copy region. The location and distribution of repeat sequences and microsatellites were determined, and the rapidly evolving chloroplast genome regions (trnK-trnQ, trnS-trnG, trnC-petN, trnE-trnT, petG-trnW-trnP, ndhF, trnL-rpl32, and ycf1) were detected. Phylogenetic relationships of Dioscorea inferred from chloroplast genomes obtained high support even in shortest internodes. Thus, chloroplast genome sequences provide potential molecular markers and genomic resources for phylogeny and species identification.

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Comparative analysis of the complete chloroplast genome sequences of six species of Pulsatilla Miller, Ranunculaceae

Chinese Medicine ◽

10.1186/s13020-019-0274-5 ◽

2019 ◽

Vol 14 (1) ◽

Cited By ~ 2

Author(s):

Tingting Zhang ◽

Yanping Xing ◽

Liang Xu ◽

Guihua Bao ◽

Zhilai Zhan ◽

...

Keyword(s):

Related Species ◽

Phylogenetic Trees ◽

Single Copy ◽

Nucleotide Polymorphisms ◽

Illumina Hiseq ◽

Closely Related Species ◽

Protein Coding ◽

Simple Sequence Repeat Analysis ◽

Chloroplast Genomes ◽

Cp Genome

Abstract Background Baitouweng is a traditional Chinese medicine with a long history of different applications. Although referred to as a single medicine, Baitouweng is actually comprised of many closely related species. It is therefore critically important to identify the different species that are utilized in these medicinal applications. Knowledge about their phylogenetic relationships can be derived from their chloroplast genomes and may provide additional insights into development of molecular markers. Methods Genomic DNA was extracted from six species of Pulsatilla and then sequenced on an Illumina HiSeq 4000. Sequences were assembled into contigs by SOAPdenovo 2.04, aligned to the reference genome using BLAST, and then manually corrected. Genome annotation was performed by the online DOGMA tool. General characteristics of the cp genomes of the six species were analyzed and compared with closely related species. Additionally, phylogenetic trees were constructed, based on single nucleotide polymorphisms (SNPs) and 51 shared protein-coding gene sequences in the cp genome among all 31 species via maximum likelihood. Results The size of cp genomes of P. chinensis (Bge.) Regel, P. chinensis (Bge.) Regel var. kissii (Mandl) S. H. Li et Y. H. Huang, P. cernua (Thunb.) Bercht. et Opiz f. plumbea J. X. Ji et Y. T. zhao, P. dahurica (Fisch.) Spreng, P. turczaninovii Kryl. et Serg, and P. cernua (Thunb.) Bercht. et Opiz. were 163,851 bp, 163,756 bp, 162,481 bp, 162,450 bp, 162,795 bp, and 162,924 bp, respectively. Each species included two inverted repeat regions, a small single-copy region, and a large single-copy region. A total of 134 genes were annotated, including 90 protein-coding genes, 36 tRNAs, and eight rRNAs across all species. In simple sequence repeat analysis, only P. dahurica was found to contain hexanucleotide repeats. A total of 26, 39, 32, 37, 32 and 43 large repeat sequences were identified in the genic regions of the six Pulsatilla species. Nucleotide diversity analysis revealed that the rpl36 gene and ccsA-ndhD region have the highest Pi value. In addition, two phylogenetic trees of the cp genomes were constructed, which laced all Pulsatilla species into one branch within Ranunculaceae. Conclusions We identified and analyzed the cp genome features of six species of P. Miller, with implications for species identification and phylogenetic analysis.

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Chloroplast Genome of Phyllanthus Emblica and Leptopus Cordifolius: Comparative Analysis and Phylogenetic within Family Phyllanthaceae

10.20944/preprints202107.0094.v1 ◽

2021 ◽

Author(s):

Umar Rehman ◽

Nighat Sultana ◽

Abdullah . ◽

Abbas Jamal ◽

Maryam Muzaffar ◽

...

Keyword(s):

Chloroplast Genome ◽

Related Species ◽

Gc Content ◽

Single Copy ◽

Phyllanthus Emblica ◽

Protein Coding ◽

Coding Sequences ◽

Tropical Regions ◽

Chloroplast Genomes ◽

The Family

Family Phyllanthaceae is one of the largest segregates of the eudicot order Malpighiales and its species are herb, shrub, and tree, which are mostly distributed in tropical regions. Certain taxonomic discrepancies exist at genus and family level. Here, we report chloroplast genomes of three Phyllanthaceae species—Phyllanthus emblica, Flueggea virosa, and Leptopus cordifolius— and compare them with six others previously reported Phyllanthaceae chloroplast genomes. The species of Phyllanthaceae displayed quadripartite structure, comprising inverted repeat regions (IRa and IRb) that separate large single copy (LSC) and small single copy (SSC) regions. The length of complete chloroplast genome ranged from 154,707 bp to 161,093 bp; LSC from 83,627 bp to 89,932 bp; IRs from 23,921 bp to 27,128 bp; and SSC from 17,424 bp to 19,441 bp. Chloroplast genomes contained 111 to 112 unique genes, including 77 to 78 protein-coding, 30 transfer RNA (tRNA), and 4 ribosomal RNA (rRNA) that showed similarities in arrangement. The number of protein-coding genes varied due to deletion/pseudogenization of rps16 genes in Baccaurea ramiflora and Leptopus cordifolius. High variability was seen in number of oligonucleotide repeats while analysis of guanine-cytosine (GC) content, codon usage, amino acid frequency, simple sequence repeats analysis, synonymous and non-synonymous substitutions, and transition and transversion substitutions showed similarities in all Phyllanthaceae species. We detected a higher number of transition substitutions in the coding sequences than non-coding sequences. Moreover, the high number of transition substitutions was determined among the distantly related species in comparison to closely related species. Phylogenetic analysis shows the polyphyletic nature of the genus Phyllanthus which requires further verification. We also determined suitable polymorphic coding genes, including rpl22, ycf1, matK, ndhF, and rps15 which may be helpful for the reconstruction of the high-resolution phylogenetic tree of the family Phyllanthaceae using a large number of species in the future. Overall, the current study provides insight into chloroplast genome evolution in Phyllanthaceae.

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Development of a Reference Standard Library of Chloroplast Genome Sequences, GenomeTrakrCP

Planta Medica ◽

10.1055/s-0043-113449 ◽

2017 ◽

Vol 83 (18) ◽

pp. 1420-1430 ◽

Cited By ~ 12

Author(s):

Ning Zhang ◽

Padmini Ramachandran ◽

Jun Wen ◽

James Duke ◽

Helen Metzman ◽

...

Keyword(s):

Dietary Supplements ◽

Chloroplast Genome ◽

Related Species ◽

Sequencing Data ◽

Genome Sequences ◽

Closely Related Species ◽

Chloroplast Genomes ◽

Processed Products ◽

Species Specific ◽

Close Relatives

AbstractPrecise, species-level identification of plants in foods and dietary supplements is difficult. While the use of DNA barcoding regions (short regions of DNA with diagnostic utility) has been effective for many inquiries, it is not always a robust approach for closely related species, especially in highly processed products. The use of fully sequenced chloroplast genomes, as an alternative to short diagnostic barcoding regions, has demonstrated utility for closely related species. The U. S. Food and Drug Administration (FDA) has also developed species-specific DNA-based assays targeting plant species of interest by utilizing chloroplast genome sequences. Here, we introduce a repository of complete chloroplast genome sequences called GenomeTrakrCP, which will be publicly available at the National Center for Biotechnology Information (NCBI). Target species for inclusion are plants found in foods and dietary supplements, toxin producers, common contaminants and adulterants, and their close relatives. Publicly available data will include annotated assemblies, raw sequencing data, and voucher information with each NCBI accession associated with an authenticated reference herbarium specimen. To date, 40 complete chloroplast genomes have been deposited in GenomeTrakrCP (https://www.ncbi.nlm.nih.gov/bioproject/PRJNA325670/), and this will be expanded in the future.

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Insights into chloroplast genome variation across Opuntioideae (Cactaceae)

10.1101/2020.03.06.981183 ◽

2020 ◽

Cited By ~ 1

Author(s):

Matias Köhler ◽

Marcelo Reginato ◽

Tatiana T. Souza-Chies ◽

Lucas C. Majure

Keyword(s):

Chloroplast Genome ◽

De Novo ◽

Single Copy ◽

Physiological Constraints ◽

Chloroplast Genomes ◽

The Family ◽

The Common ◽

And Inversion ◽

Small Single Copy ◽

High Support

AbstractChloroplast genomes (plastomes) are frequently treated as highly conserved among land plants. However, many lineages of vascular plants have experienced extensive structural rearrangements, including inversions and modifications to the size and content of genes. Cacti are one of these lineages, containing the smallest plastome known for an obligately photosynthetic angiosperm, including the loss of one copy of the inverted repeat (∼25 kb) and the ndh genes suite, but only a few cacti from the subfamily Cactoideae have been sufficiently characterized. Here, we investigated the variation of plastome sequences across the second-major lineage of the Cactaceae, the subfamily Opuntioideae, to address 1) how variable is the content and arrangement of chloroplast genome sequences across the subfamily, and 2) how phylogenetically informative are the plastome sequences for resolving major relationships among the clades of Opuntioideae. Our de novo assembly of the Opuntia quimilo plastome recovered an organelle of 150,347 bp in length with both copies of the inverted repeats and the presence of all the ndh genes suite. An expansion of the large single copy unit and a reduction of the small single copy was observed, including translocations and inversion of genes as well as the putative pseudogenization of numerous loci. Comparative analyses among all clades within Opuntioideae suggested that plastome structure and content vary across taxa of this subfamily, with putative independent losses of the ndh gene suite and pseudogenization of genes across disparate lineages, further demonstrating the dynamic nature of plastomes in Cactaceae. Our plastome dataset was robust in determining relationships among major clades and subclades within Opuntioideae, resolving three tribes with high support: Cylindropuntieae, Tephrocacteae and Opuntieae. A plastome-wide survey for highly informative phylogenetic markers revealed previously unused regions for future use in Sanger-based studies, presenting a valuable dataset with primers designed for continued evolutionary studies across Cactaceae. These results bring new insights into the evolution of plastomes in cacti, suggesting that further analyses should be carried out to address how ecological drivers, physiological constraints and morphological traits of cacti may be related with the common rearrangements in plastomes that have been reported across the family.

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Phylogenetic analysis of Fritillaria cirrhosa D. Don and its closely related species based on complete chloroplast genomes

PeerJ ◽

10.7717/peerj.7480 ◽

2019 ◽

Vol 7 ◽

pp. e7480 ◽

Cited By ~ 5

Author(s):

Qi Chen ◽

Xiaobo Wu ◽

Dequan Zhang

Keyword(s):

Chloroplast Genome ◽

Related Species ◽

Phylogenetic Relationships ◽

Phylogenetic Analyses ◽

Gc Content ◽

Closely Related Species ◽

Complete Chloroplast Genome ◽

Plastid Genomes ◽

Chloroplast Genomes ◽

Fritillaria Cirrhosa

Fritillaria cirrhosa D. Don, whose bulb is used in a well-known traditional Chinese medicine to relieve cough and eliminate phlegm, is one of the most important medicinal plants of Fritillaria L. The species is widely distributed among the alpine regions in southwestern China and possesses complex morphological variations in different distributions. A series of newly related species were reported, based on obscure morphological differences. As a result, F. cirrhosa and its closely related species constitute a taxonomically complex group. However, it is difficult to accurately identify these species and reveal their phylogenetic relationships using traditional taxonomy. Molecular markers and gene fragments have been adopted but they are not able to afford sufficient phylogenetic resolution in the genus. Here, we report the complete chloroplast genome sequences of F. cirrhosa and its closely related species using next generation sequencing (NGS) technology. Eight plastid genomes ranged from 151,058 bp to 152,064 bp in length and consisted of 115 genes. Gene content, gene order, GC content, and IR/SC boundary structures were highly similar among these genomes. SSRs and five large repeat sequences were identified and the total number of them ranged from 73 to 79 and 63 to 75, respectively. Six highly divergent regions were successfully identified that could be used as potential genetic markers of Fritillaria. Phylogenetic analyses revealed that eight Fritillaria species were clustered into three clades with strong supports and F. cirrhosa was closely related to F. przewalskii and F. sinica. Overall, this study indicated that the complete chloroplast genome sequence was an efficient tool for identifying species in taxonomically complex groups and exploring their phylogenetic relationships.

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