Complete Chloroplast Genomes and Comparative Analysis of Sequences Evolution among Seven Aristolochia (Aristolochiaceae) Medicinal Species

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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Complete Chloroplast Genomes from Sanguisorba: Identity and Variation Among Four Species

Molecules ◽

10.3390/molecules23092137 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2137 ◽

Cited By ~ 6

Author(s):

Xiang-Xiao Meng ◽

Yan-Fang Xian ◽

Li Xiang ◽

Dong Zhang ◽

Yu-Hua Shi ◽

...

Keyword(s):

Gc Content ◽

Single Copy ◽

Rrna Genes ◽

Trna Genes ◽

Protein Coding ◽

Future Studies ◽

Chloroplast Genomes ◽

Close Relationship ◽

Cp Genome ◽

Sanguisorba Officinalis

The genus Sanguisorba, which contains about 30 species around the world and seven species in China, is the source of the medicinal plant Sanguisorba officinalis, which is commonly used as a hemostatic agent as well as to treat burns and scalds. Here we report the complete chloroplast (cp) genome sequences of four Sanguisorba species (S. officinalis, S. filiformis, S. stipulata, and S. tenuifolia var. alba). These four Sanguisorba cp genomes exhibit typical quadripartite and circular structures, and are 154,282 to 155,479 bp in length, consisting of large single-copy regions (LSC; 84,405–85,557 bp), small single-copy regions (SSC; 18,550–18,768 bp), and a pair of inverted repeats (IRs; 25,576–25,615 bp). The average GC content was ~37.24%. The four Sanguisorba cp genomes harbored 112 different genes arranged in the same order; these identical sections include 78 protein-coding genes, 30 tRNA genes, and four rRNA genes, if duplicated genes in IR regions are counted only once. A total of 39–53 long repeats and 79–91 simple sequence repeats (SSRs) were identified in the four Sanguisorba cp genomes, which provides opportunities for future studies of the population genetics of Sanguisorba medicinal plants. A phylogenetic analysis using the maximum parsimony (MP) method strongly supports a close relationship between S. officinalis and S. tenuifolia var. alba, followed by S. stipulata, and finally S. filiformis. The availability of these cp genomes provides valuable genetic information for future studies of Sanguisorba identification and provides insights into the evolution of the genus Sanguisorba.

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Characterization of the complete chloroplast genome sequence and phylogenetic analysis of B. oleracea var. italica

10.21203/rs.2.20976/v1 ◽

2020 ◽

Author(s):

Zhenchao Zhang ◽

Zhongliang Dai ◽

Yuemei Yao ◽

Yongfei Pan ◽

Guosheng Sun ◽

...

Keyword(s):

Chloroplast Genome ◽

Genome Sequence ◽

Genomic Structure ◽

Gc Content ◽

Single Copy ◽

Biological Research ◽

Protein Coding ◽

Protein Coding Genes ◽

Cp Genome ◽

Functional Components

Abstract Backgrounds: Broccoli (Brassica. oleracea var. italica L.) is known as one of the most nutritionally rich vegetables, as well as rich in functional components that benefit to health. The main purposes of this research were sequencing, assembling and annotation of chloroplast genome of broccoli based on Illumina HiSeq2500 sequencing platform. Results: The size of the broccoli cp genome is 153,364 bp, including two inverted repeat (IR) regions of 26,197 bp each, separated by a small single copy (SSC) region of 17,834 bp and a large single copy (LSC) region of 83,136 bp. The GC content of the complete genome is 36.36%, while those of SSC, LSC, and IR are 29.1%, 34.15% and 42.35%, respectively. It harbors 134 functional genes, including 87 protein-coding genes, 39 tRNAs and 8 rRNAs, with 31 duplicates in the IRs. The most abundant amino acid in the protein-coding genes is leucine, while the least is cysteine. Codon usage frequency showed bias for A/T-ending codons in the cp genome. In the repeat structure analysis, a total of 34 repeat sequences and 291 simple sequence repeat (SSRs) were detected in the work. Although cp genomic structure and size are highly conserved, the SC-IR boundary regions are variable between the 7 cp genomes. The phylogenetic relationships based on complete cp genome from 9 species suggest that B. oleracea var. italica is closely related to Brassica juncea. Conclusions: The complete cp genome sequence was obtained and annotated for broccoli for the first time. The information acquired from this research will be useful for further species identification, population genetics and biological research of broccoli.

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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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Initial Complete Chloroplast Genomes of Alchemilla (Rosaceae): Comparative Analysis and Phylogenetic Relationships

Frontiers in Genetics ◽

10.3389/fgene.2020.560368 ◽

2020 ◽

Vol 11 ◽

Author(s):

Peninah Cheptoo Rono ◽

Xiang Dong ◽

Jia-Xin Yang ◽

Fredrick Munyao Mutie ◽

Millicent A. Oulo ◽

...

Keyword(s):

Tandem Repeats ◽

Single Copy ◽

Rrna Genes ◽

Trna Genes ◽

Coding Region ◽

Base Pairs ◽

Protein Coding ◽

Chloroplast Genomes ◽

The Family ◽

Cp Genome

The genus Alchemilla L., known for its medicinal and ornamental value, is widely distributed in the Holarctic regions with a few species found in Asia and Africa. Delimitation of species within Alchemilla is difficult due to hybridization, autonomous apomixes, and polyploidy, necessitating efficient molecular-based characterization. Herein, we report the initial complete chloroplast (cp) genomes of Alchemilla. The cp genomes of two African (Afromilla) species Alchemilla pedata and Alchemilla argyrophylla were sequenced, and phylogenetic and comparative analyses were conducted in the family Rosaceae. The cp genomes mapped a typical circular quadripartite structure of lengths 152,438 and 152,427 base pairs (bp) in A. pedata and A. argyrophylla, respectively. Alchemilla cp genomes were composed of a pair of inverted repeat regions (IRa/IRb) of length 25,923 and 25,915 bp, separating the small single copy (SSC) region of 17,980 and 17,981 bp and a large single copy (LSC) region of 82,612 and 82,616 bp in A. pedata and A. argyrophylla, respectively. The cp genomes encoded 114 unique genes including 88 protein-coding genes, 37 transfer RNA (tRNA) genes, and 4 ribosomal RNA (rRNA) genes. Additionally, 88 and 95 simple sequence repeats (SSRs) and 37 and 40 tandem repeats were identified in A. pedata and A. argyrophylla, respectively. Significantly, the loss of group II intron in atpF gene in Alchemilla species was detected. Phylogenetic analysis based on 26 whole cp genome sequences and 78 protein-coding gene sequences of 27 Rosaceae species revealed a monophyletic clustering of Alchemilla nested within subfamily Rosoideae. Based on a protein-coding region, negative selective pressure (Ka/Ks < 1) was detected with an average Ka/Ks value of 0.1322 in A. argyrophylla and 0.1418 in A. pedata. The availability of complete cp genome in the genus Alchemilla will contribute to species delineation and further phylogenetic and evolutionary studies in the family Rosaceae.

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A New Dinoflagellate Genome Illuminates a Conserved Gene Cluster Involved in Sunscreen Biosynthesis

Genome Biology and Evolution ◽

10.1093/gbe/evaa235 ◽

2020 ◽

Author(s):

Eiichi Shoguchi ◽

Girish Beedessee ◽

Kanako Hisata ◽

Ipputa Tada ◽

Haruhi Narisoko ◽

...

Keyword(s):

Thermal Tolerance ◽

Genomic Structure ◽

Gc Content ◽

Genomic Diversity ◽

Phylogenetic Position ◽

Neighboring Gene ◽

Protein Coding ◽

The Family ◽

Genomic Resource ◽

Conserved Gene

Abstract Photosynthetic dinoflagellates of the Family Symbiodiniaceae live symbiotically with many organisms that inhabit coral reefs and are currently classified into fifteen groups, including seven genera. Draft genomes from four genera, Symbiodinium, Breviolum, Fugacium, and Cladocopium, which have been isolated from corals, have been reported. However, no genome is available from the genus Durusdinium, which occupies an intermediate phylogenetic position in the Family Symbiodiniaceae and is well known for thermal tolerance (resistance to bleaching). We sequenced, assembled, and annotated the genome of Durusdinium trenchii, isolated from the coral, Favia speciosa, in Okinawa, Japan. Assembled short reads amounted to 670 Mbp with ∼47% GC content. This GC content was intermediate among taxa belonging to the Symbiodiniaceae. Approximately 30,000 protein-coding genes were predicted in the D. trenchii genome, fewer than in other genomes from the Symbiodiniaceae. However, annotations revealed that the D. trenchii genome encodes a cluster of genes for synthesis of mycosporine-like amino acids (MAAs), which absorb UV radiation. Interestingly, a neighboring gene in the cluster encodes a GMC (glucose-methanol-choline) oxidoreductase with an FAD (flavin adenine dinucleotide) domain that is also found in Symbiodinium tridacnidorum. This conservation seems to partially clarify an ancestral genomic structure in the Symbiodiniaceae and its loss in late-branching lineages, including Breviolum and Cladocopium, after splitting from the Durusdinium lineage. Our analysis suggests that approximately half of the taxa in the Symbiodiniaceae may maintain the ability to synthesize MAAs. Thus, this work provides a significant genomic resource for understanding the genomic diversity of Symbiodiniaceae in corals.

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Comparative Analyses of Euonymus Chloroplast Genomes: Genetic Structure, Screening for Loci With Suitable Polymorphism, Positive Selection Genes, and Phylogenetic Relationships Within Celastrineae

Frontiers in Plant Science ◽

10.3389/fpls.2020.593984 ◽

2021 ◽

Vol 11 ◽

Author(s):

Yongtan Li ◽

Yan Dong ◽

Yichao Liu ◽

Xiaoyue Yu ◽

Minsheng Yang ◽

...

Keyword(s):

Positive Selection ◽

Chloroplast Genome ◽

Gc Content ◽

Single Copy ◽

Rrna Genes ◽

Evolutionary Relationships ◽

Trna Genes ◽

Protein Coding ◽

Chloroplast Genomes ◽

Cp Genome

In this study, we assembled and annotated the chloroplast (cp) genome of the Euonymus species Euonymus fortunei, Euonymus phellomanus, and Euonymus maackii, and performed a series of analyses to investigate gene structure, GC content, sequence alignment, and nucleic acid diversity, with the objectives of identifying positive selection genes and understanding evolutionary relationships. The results indicated that the Euonymus cp genome was 156,860–157,611bp in length and exhibited a typical circular tetrad structure. Similar to the majority of angiosperm chloroplast genomes, the results yielded a large single-copy region (LSC) (85,826–86,299bp) and a small single-copy region (SSC) (18,319–18,536bp), separated by a pair of sequences (IRA and IRB; 26,341–26,700bp) with the same encoding but in opposite directions. The chloroplast genome was annotated to 130–131 genes, including 85–86 protein coding genes, 37 tRNA genes, and eight rRNA genes, with GC contents of 37.26–37.31%. The GC content was variable among regions and was highest in the inverted repeat (IR) region. The IR boundary of Euonymus happened expanding resulting that the rps19 entered into IR region and doubled completely. Such fluctuations at the border positions might be helpful in determining evolutionary relationships among Euonymus. The simple-sequence repeats (SSRs) of Euonymus species were composed primarily of single nucleotides (A)n and (T)n, and were mostly 10–12bp in length, with an obvious A/T bias. We identified several loci with suitable polymorphism with the potential use as molecular markers for inferring the phylogeny within the genus Euonymus. Signatures of positive selection were seen in rpoB protein encoding genes. Based on data from the whole chloroplast genome, common single copy genes, and the LSC, SSC, and IR regions, we constructed an evolutionary tree of Euonymus and related species, the results of which were consistent with traditional taxonomic classifications. It showed that E. fortunei sister to the Euonymus japonicus, whereby E. maackii appeared as sister to Euonymus hamiltonianus. Our study provides important genetic information to support further investigations into the phylogenetic development and adaptive evolution of Euonymus species.

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Comparative Analysis of the Complete Chloroplast Genomes of Four Chestnut Species (Castanea)

Forests ◽

10.3390/f12070861 ◽

2021 ◽

Vol 12 (7) ◽

pp. 861

Author(s):

Huijuan Zhou ◽

Xiaoxiao Gao ◽

Keith Woeste ◽

Peng Zhao ◽

Shuoxin Zhang

Keyword(s):

Comparative Analysis ◽

Phylogenetic Analyses ◽

Single Copy ◽

Nucleotide Substitutions ◽

Protein Coding ◽

Variable Regions ◽

Chloroplast Genomes ◽

Cp Genome ◽

Species Hybrids ◽

Rna Genes

Chloroplast (cp) DNA genomes are traditional workhorses for studying the evolution of species and reconstructing phylogenetic relationships in plants. Species of the genus Castanea (chestnuts and chinquapins) are valued as a source of nuts and timber wherever they grow, and chestnut species hybrids are common. We compared the cp genomes of C. mollissima, C. seguinii, C. henryi, and C. pumila. These cp genomes ranged from 160,805 bp to 161,010 bp in length, comprising a pair of inverted repeat (IR) regions (25,685 to 25,701 bp) separated by a large single-copy (LSC) region (90,440 to 90,560 bp) and a small single-copy (SSC) region (18,970 to 19,049 bp). Each cp genome encoded the same 113 genes; 82–83 protein-coding genes, 30 transfer RNA genes, and four ribosomal RNA genes. There were 18 duplicated genes in the IRs. Comparative analysis of cp genomes revealed that rpl22 was absent in all analyzed species, and the gene ycf1 has been pseudo-genized in all Chinese chestnuts except C. pumlia. We analyzed the repeats and nucleotide substitutions in these plastomes and detected several highly variable regions. The phylogenetic analyses based on plastomes confirmed the monophyly of Castanea species.

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Comparative Chloroplast Genomes of Four Lycoris Species (Amaryllidaceae) Provides New Insight into Interspecific Relationship and Phylogeny

Biology ◽

10.3390/biology10080715 ◽

2021 ◽

Vol 10 (8) ◽

pp. 715

Author(s):

Fengjiao Zhang ◽

Ning Wang ◽

Guanghao Cheng ◽

Xiaochun Shu ◽

Tao Wang ◽

...

Keyword(s):

Large Scale ◽

Phylogenetic Analyses ◽

Gc Content ◽

Natural Hybridization ◽

Comparative Genomic ◽

Protein Coding ◽

Chloroplast Genomes ◽

A Genome ◽

Cp Genome ◽

Conserved Gene

The genus Lycoris (Amaryllidaceae) consists of about 20 species, which is endemic to East Asia. Although the Lycoris species is of great horticultural and medical importance, challenges in accurate species identification persist due to frequent natural hybridization and large-scale intraspecific variation. In this study, we sequenced chloroplast genomes of four Lycoris species and retrieved seven published chloroplast (cp) genome sequences in this genus for comparative genomic and phylogenetic analyses. The cp genomes of these four newly sequenced species were found to be 158,405–158,498 bp with the same GC content of 37.8%. The structure of the genomes exhibited the typical quadripartite structure with conserved gene order and content. A total of 113 genes (20 duplicated) were identified, including 79 protein-coding genes (PCGs), 30 tRNAs, and 4 rRNAs. Phylogenetic analysis showed that the 11 species were clustered into three main groups, and L. sprengeri locate at the base of Lycoriss. The L. radiata was suggested to be the female donor of the L. incarnata, L. shaanxiensis, and L. squamigera. The L. straminea and L. houdyshelii may be derived from L. anhuiensis, L. chinensis, or L. longituba. These results could not only offer a genome-scale platform for identification and utilization of Lycoris but also provide a phylogenomic framework for future studies in this genus.

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Characterization of the complete chloroplast genomes of five Populus species from the western Sichuan plateau, southwest China: comparative and phylogenetic analyses

PeerJ ◽

10.7717/peerj.6386 ◽

2019 ◽

Vol 7 ◽

pp. e6386 ◽

Cited By ~ 6

Author(s):

Dan Zong ◽

Anpei Zhou ◽

Yao Zhang ◽

Xinlian Zou ◽

Dan Li ◽

...

Keyword(s):

Phylogenetic Analyses ◽

Molecular Genetic ◽

Gc Content ◽

Rrna Genes ◽

Trna Genes ◽

Nucleotide Substitutions ◽

Protein Coding ◽

Western Sichuan ◽

Protein Coding Genes ◽

Chloroplast Genomes

Species of the genus Populus, which is widely distributed in the northern hemisphere from subtropical to boreal forests, are among the most commercially exploited groups of forest trees. In this study, the complete chloroplast genomes of five Populus species (Populus cathayana, P. kangdingensis, P. pseudoglauca, P. schneideri, and P. xiangchengensis) were compared. The chloroplast genomes of the five Populus species are very similar. The total chloroplast genome sequence lengths for the five plastomes were 156,789, 156,523, 156,512, 156,513, and 156,465 bp, respectively. A total of 130 genes were identified in each genome, including 85 protein-coding genes, 37 tRNA genes and eight rRNA genes. Seven genes were duplicated in the protein-coding genes, whereas 11 genes were duplicated in the RNA genes. The GC content was 36.7% for all plastomes. We analyzed nucleotide substitutions, small inversions, simple sequence repeats and long repeats in the chloroplast genomes and found nine divergence hotspots (ccsA+ccsA-ndhD, ndhC-trnV, psbZ-trnfM, trnG-atpA, trnL-ndhJ, trnR-trnN, ycf4-cemA, ycf1, and trnR-trnN), which could be useful molecular genetic markers for future population genetic and phylogenetic studies. We also observed that two genes (rpoC2 and rbcL) were subject to positive selection. Phylogenetic analysis based on whole cp genomes showed that P. schneideri had a close relationship with P. kangdingensis and P. pseudoglauca, while P. xiangchengensis was a sister to P. cathayana.

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Complete chloroplast genomes of Rubus species (Rosaceae) and comparative analysis within the genus

BMC Genomics ◽

10.1186/s12864-021-08225-6 ◽

2022 ◽

Vol 23 (1) ◽

Author(s):

Jiaojun Yu ◽

Jun Fu ◽

Yuanping Fang ◽

Jun Xiang ◽

Hongjin Dong

Keyword(s):

Comparative Analysis ◽

Ornamental Plants ◽

Gc Content ◽

Central China ◽

Dabie Mountains ◽

Nucleotide Variability ◽

Chloroplast Genomes ◽

The Family ◽

Cp Genome ◽

Rna Genes

Abstract Background Rubus is the largest genus of the family Rosaceae and is valued as medicinal, edible, and ornamental plants. Here, we sequenced and assembled eight chloroplast (cp) genomes of Rubus from the Dabie Mountains in Central China. Fifty-one Rubus species were comparatively analyzed for the cp genomes including the eight newly discovered genomes and forty-three previously reported in GenBank database (NCBI). Results The eight newly obtained cp genomes had the same quadripartite structure as the other cp genomes in Rubus. The length of the eight plastomes ranged from 155,546 bp to 156,321 bp with similar GC content (37.0 to 37.3%). The results indicated 133–134 genes were annotated for the Rubus plastomes, which contained 88 or 89 protein coding genes (PCGs), 37 transfer RNA genes (tRNAs), and eight ribosomal RNA genes (rRNAs). Among them, 16 (or 18) of the genes were duplicated in the IR region. Structural comparative analysis results showed that the gene content and order were relatively preserved. Nucleotide variability analysis identified nine hotspot regions for genomic divergence and multiple simple sequences repeats (SSRs), which may be used as markers for genetic diversity and phylogenetic analysis. Phylogenetic relationships were highly supported within the family Rosaceae, as evidenced by sub-clade taxa cp genome sequences. Conclusion Thus, the whole plastome may be used as a super-marker in phylogenetic studies of this genus.

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