scholarly journals Insights into Comparative Genomics, Codon Usage Bias, and Phylogenetic Relationship of Species from Biebersteiniaceae and Nitrariaceae Based on Complete Chloroplast Genomes

Plants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1605
Author(s):  
Xiaofeng Chi ◽  
Faqi Zhang ◽  
Qi Dong ◽  
Shilong Chen
Keyword(s):  
Codon Usage ◽  
Codon Usage Bias ◽  
High Similarity ◽  
Peganum Harmala ◽  
Protein Coding ◽  
Variable Regions ◽  
Chloroplast Genomes ◽  
Nitraria Sibirica ◽  
Effective Number Of Codons ◽  
Relationship Of

Biebersteiniaceae and Nitrariaceae, two small families, were classified in Sapindales recently. Taxonomic and phylogenetic relationships within Sapindales are still poorly resolved and controversial. In current study, we compared the chloroplast genomes of five species (Biebersteinia heterostemon, Peganum harmala, Nitraria roborowskii, Nitraria sibirica, and Nitraria tangutorum) from Biebersteiniaceae and Nitrariaceae. High similarity was detected in the gene order, content and orientation of the five chloroplast genomes; 13 highly variable regions were identified among the five species. An accelerated substitution rate was found in the protein-coding genes, especially clpP. The effective number of codons (ENC), parity rule 2 (PR2), and neutrality plots together revealed that the codon usage bias is affected by mutation and selection. The phylogenetic analysis strongly supported (Nitrariaceae (Biebersteiniaceae + The Rest)) relationships in Sapindales. Our findings can provide useful information for analyzing phylogeny and molecular evolution within Biebersteiniaceae and Nitrariaceae.

scholarly journals Comparative Genomics and Phylogenetic Analyses of Christia vespertilionis and Urariopsis brevissima in the Tribe Desmodieae (Fabaceae: Papilionoideae) Based on Complete Chloroplast Genomes

Plants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1116 ◽  
Author(s):  
Xue-Li Zhao ◽  
Zhang-Ming Zhu
Keyword(s):  
Phylogenetic Analyses ◽  
Evolutionary Process ◽  
Rrna Genes ◽  
Trna Genes ◽  
Sister Relationship ◽  
Protein Coding ◽  
Variable Regions ◽  
Chloroplast Genomes ◽  
Distinct Genus ◽  
Relationship Of

Taxonomic and phylogenetic relationships of Christia, Urariopsis, Uraria and related genera within the tribe Desmodieae (Fabaceae: Papilionoideae) have long been controversial. Here, we report the complete chloroplast (cp) genomes of Christia vespertilionis and Urariopsis brevissima and perform comparative and phylogenetic analyses with Uraria lagopodioides and other relatives in the Desmodieae. The cp genomes of C. vespertilionis and U. brevissima are 149,656 and 149,930 bp long, with 128 unique genes (83 protein-coding genes, 37 tRNA genes and 8 rRNA genes), respectively. Comparative analyses revealed 95-129 simple sequence repeats (SSRs) and eleven highly variable regions (trnK-rbcL, rbcL-atpB, ndhJ-trnF, trnL-trnT, psbD-rpoB, accD-cemA, petA-psbL, psbE-petL, rps11-rps19, ndhF-ccsA, and rps15-ycf1) among six Desmodieae species. Phylogenetic analyses clearly resolved two subtribes (Desmodiinae and Lespedezinae) of Desmodieae as monophyletic, and the newly reported C. vespertilionis and U. brevissima clustered in subtribe Desmodiinae. A sister relationship of C. vespertilionis to U. lagopodioides was supported. Evidence was presented to support the treatment of Urariopsis as a distinct genus rather than in synonymy with Uraria. The results provide valuable information for further studies on species delimitation, phylogenetics, population genetics, and the evolutionary process of speciation in the Desmodieae.

scholarly journals Complete Chloroplast Genome Sequences of Three Aroideae Species (Araceae): Lights into Selective Pressure, Marker Development and Phylogenetic Relationships

2021 ◽  
Author(s):  
Bicong Li ◽  
Tao Liu ◽  
Asjad Ali ◽  
Yao Xiao ◽  
Nan Shan ◽  
...  
Keyword(s):  
Dna Barcodes ◽  
Protein Coding ◽  
Variable Regions ◽  
Complete Chloroplast Genome ◽  
Protein Coding Genes ◽  
Chloroplast Genomes ◽  
Xanthosoma Sagittifolium ◽  
Close Relationship ◽  
Relationship Of ◽  
First Time

Abstract Background : Colocasia gigantea, Caladium bicolor and Xanthosoma sagittifolium are three worldwide famous ornamental and/or vegetable plants in the Araceae family, these species in the subfamily Aroideae are taxonomically perplexing due to shared interspecific morphological traits and variation.Result : This study, for the first time ever, assembled and analyzed complete chloroplast genomes of C. gigantea, C. bicolor and X. sagittifolium with genome sizes of 165,906 bp, 153,149 bp and 165,169 bp in length, respectively. The genomes were composed of conserved quadripartite circular structures with a total of 131 annotated genes, including 8 rRNA, 37 tRNA and 86 protein-coding genes. A comparison within Aroideae showed seven protein-coding genes (accD, ndhF, ndhK, rbcL, rpoC1, rpoC2 and matK) linked to environmental adaptation. Phylogenetic analysis confirmed a close relationship of C. gigantea with C. esculenta and S. colocasiifolia, and the C. bicolor with X. sagittifolium. Furthermore, three DNA barcodes (atpH-atpI + psaC-ndhE, atpH-atpI + trnS-trnG, atpH-atpI + psaC-ndhE + trnS-trnG) harbored highly variable regions to distinguish species in Aroideae subfamily.Conclusion : These results would be beneficial for species identification, phylogenetic relationship, genetic diversity, and potential of germplasm resources in Aroideae.

scholarly journals Comparative analysis of chloroplast genomes for five Dicliptera species (Acanthaceae): molecular structure, phylogenetic relationships, and adaptive evolution

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8450 ◽  
Author(s):  
Sunan Huang ◽  
Xuejun Ge ◽  
Asunción Cano ◽  
Betty Gaby Millán Salazar ◽  
Yunfei Deng
Keyword(s):  
Adaptive Evolution ◽  
Phylogenetic Relationships ◽  
Single Copy ◽  
Rrna Genes ◽  
Trna Genes ◽  
Evolutionary Analysis ◽  
Protein Coding ◽  
Variable Regions ◽  
Protein Coding Genes ◽  
Chloroplast Genomes

The genus Dicliptera (Justicieae, Acanthaceae) consists of approximately 150 species distributed throughout the tropical and subtropical regions of the world. Newly obtained chloroplast genomes (cp genomes) are reported for five species of Dilciptera (D. acuminata, D. peruviana, D. montana, D. ruiziana and D. mucronata) in this study. These cp genomes have circular structures of 150,689–150,811 bp and exhibit quadripartite organizations made up of a large single copy region (LSC, 82,796–82,919 bp), a small single copy region (SSC, 17,084–17,092 bp), and a pair of inverted repeat regions (IRs, 25,401–25,408 bp). Guanine-Cytosine (GC) content makes up 37.9%–38.0% of the total content. The complete cp genomes contain 114 unique genes, including 80 protein-coding genes, 30 transfer RNA (tRNA) genes, and four ribosomal RNA (rRNA) genes. Comparative analyses of nucleotide variability (Pi) reveal the five most variable regions (trnY-GUA-trnE-UUC, trnG-GCC, psbZ-trnG-GCC, petN-psbM, and rps4-trnL-UUA), which may be used as molecular markers in future taxonomic identification and phylogenetic analyses of Dicliptera. A total of 55-58 simple sequence repeats (SSRs) and 229 long repeats were identified in the cp genomes of the five Dicliptera species. Phylogenetic analysis identified a close relationship between D. ruiziana and D. montana, followed by D. acuminata, D. peruviana, and D. mucronata. Evolutionary analysis of orthologous protein-coding genes within the family Acanthaceae revealed only one gene, ycf15, to be under positive selection, which may contribute to future studies of its adaptive evolution. The completed genomes are useful for future research on species identification, phylogenetic relationships, and the adaptive evolution of the Dicliptera species.

scholarly journals Codon Usage in the Iflaviridae Family Is Not Diverse Though the Family Members Are Isolated from Diverse Host Taxa

Viruses ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1087 ◽  
Author(s):  
Sheng-Lin Shi ◽  
Run-Xi Xia
Keyword(s):  
Codon Usage ◽  
Codon Usage Bias ◽  
Synonymous Codon ◽  
Nucleotide Composition ◽  
Effective Number ◽  
Bias Analysis ◽  
The Family ◽  
Usage Patterns ◽  
Codon Positions ◽  
Effective Number Of Codons

All iflavirus members belong to the unique genus, Iflavirus, of the family, Iflaviridae. The host taxa and sequence identities of these viruses are diverse. A codon usage bias, maintained by a balance between selection, mutation, and genetic drift, exists in a wide variety of organisms. We characterized the codon usage patterns of 44 iflavirus genomes that were isolated from the classes, Insecta, Arachnida, Mammalia, and Malacostraca. Iflaviruses lack a strong codon usage bias when they are evaluated using an effective number of codons. The odds ratios of the majority of dinucleotides are within the normal range. However, the dinucleotides at the 1st–2nd codon positions are more biased than those at the 2nd–3rd codon positions. Plots of effective numbers of codons, relative neutrality analysis, and PR2 bias analysis all indicate that selection pressure dominates mutations in shaping codon usage patterns in the family, Iflaviridae. When these viruses were grouped into their host taxa, we found that the indices, including the nucleotide composition, effective number of codons, relative synonymous codon usage, and the influencing factors behind the codon usage patterns, all show that there are non-significant differences between the six host-taxa-groups. Our results disagree with our assumption that diverse viruses should possess diverse codon usage patterns, suggesting that the nucleotide composition and codon usage in the family, Iflaviridae, are not host taxa-specific signatures.

scholarly journals The First Glimpse of Streptocarpus ionanthus (Gesneriaceae) Phylogenomics: Analysis of Five Subspecies’ Chloroplast Genomes

Plants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 456 ◽  
Author(s):  
Cornelius M. Kyalo ◽  
Zhi-Zhong Li ◽  
Elijah M. Mkala ◽  
Itambo Malombe ◽  
Guang-Wan Hu ◽  
...  
Keyword(s):  
Phylogenetic Relationships ◽  
Sequence Data ◽  
Structural Features ◽  
Base Pairs ◽  
Protein Coding ◽  
Variable Regions ◽  
Morphological Heterogeneity ◽  
Chloroplast Genomes ◽  
Chloroplast Genome Sequence ◽  
Phylogenomic Analyses

Streptocarpus ionanthus (Gesneriaceae) comprise nine herbaceous subspecies, endemic to Kenya and Tanzania. The evolution of Str. ionanthus is perceived as complex due to morphological heterogeneity and unresolved phylogenetic relationships. Our study seeks to understand the molecular variation within Str. ionanthus using a phylogenomic approach. We sequence the chloroplast genomes of five subspecies of Str. ionanthus, compare their structural features and identify divergent regions. The five genomes are identical, with a conserved structure, a narrow size range (170 base pairs (bp)) and 115 unique genes (80 protein-coding, 31 tRNAs and 4 rRNAs). Genome alignment exhibits high synteny while the number of Simple Sequence Repeats (SSRs) are observed to be low (varying from 37 to 41), indicating high similarity. We identify ten divergent regions, including five variable regions (psbM, rps3, atpF-atpH, psbC-psbZ and psaA-ycf3) and five genes with a high number of polymorphic sites (rps16, rpoC2, rpoB, ycf1 and ndhA) which could be investigated further for phylogenetic utility in Str. ionanthus. Phylogenomic analyses here exhibit low polymorphism within Str. ionanthus and poor phylogenetic separation, which might be attributed to recent divergence. The complete chloroplast genome sequence data concerning the five subspecies provides genomic resources which can be expanded for future elucidation of Str. ionanthus phylogenetic relationships.

scholarly journals A novel framework for evaluating the performance of codon usage bias metrics

2018 ◽  
Vol 15 (138) ◽  
pp. 20170667 ◽  
Author(s):  
Sophia S. Liu ◽  
Adam J. Hockenberry ◽  
Michael C. Jewett ◽  
Luís A. N. Amaral
Keyword(s):  
Codon Usage ◽  
Dna Sequences ◽  
Codon Usage Bias ◽  
False Negative ◽  
Gc Content ◽  
Sequence Length ◽  
Protein Coding ◽  
Cellular Processes ◽  
Negative Findings ◽  
Measured Effect

The unequal utilization of synonymous codons affects numerous cellular processes including translation rates, protein folding and mRNA degradation. In order to understand the biological impact of variable codon usage bias (CUB) between genes and genomes, it is crucial to be able to accurately measure CUB for a given sequence. A large number of metrics have been developed for this purpose, but there is currently no way of systematically testing the accuracy of individual metrics or knowing whether metrics provide consistent results. This lack of standardization can result in false-positive and false-negative findings if underpowered or inaccurate metrics are applied as tools for discovery. Here, we show that the choice of CUB metric impacts both the significance and measured effect sizes in numerous empirical datasets, raising questions about the generality of findings in published research. To bring about standardization, we developed a novel method to create synthetic protein-coding DNA sequences according to different models of codon usage. We use these benchmark sequences to identify the most accurate and robust metrics with regard to sequence length, GC content and amino acid heterogeneity. Finally, we show how our benchmark can aid the development of new metrics by providing feedback on its performance compared to the state of the art.

scholarly journals Codon Usage Bias of the Wheat Flower Development Gene WAG-2 and Other AGAMOUS Group Genes

2017 ◽  
Vol 9 (9) ◽  
pp. 56
Author(s):  
Wenhan Hu ◽  
Shuhong Wei
Keyword(s):  
Codon Usage ◽  
Codon Usage Bias ◽  
Codon Bias ◽  
Target Genes ◽  
Expression System ◽  
Functional Studies ◽  
Codon Preference ◽  
Synonymous Codons ◽  
The Difference ◽  
Relationship Of

Analyzing codon usage bias of WAG-2 gene in wheat three-pistil (TP) mutant may provide a basis for selecting the appropriate host expression systems to improve the expression of target genes. In the present study, we analyzed the codon bias of the complete coding sequence (CDS) of the WAG-2 gene in TP using Codon W program, and compared the results with AGAMOUS (AG) group genes of other plant species. Results showed that the WAG-2 gene in TP and other monocot AG group genes preferably used codons ending with G/C bases, but Arabidopsis thaliana, Nicotiana tabacum, and other dicot crops were biased toward the synonymous codons with A/T. The clustering results based on codon bias were consistent with those based on CDS of the AG group genes, indicating that the difference in codon preference of AG group genes sequences was closely associated with the genetic relationship of the species. The Euclidean distance coefficients of WAG-2 with A. thaliana and N. tabacum were 9.255 and 5.730, respectively, indicating that N. tabacum may be more suitable for the expression of WAG-2. There were 37 codons showing distinct usage differences between WAG-2 and genome of yeast, 23 between WAG-2 and Escherichia coli. Therefore, the E. coli was the superior protein expression system. These results may improve our understanding of codon usage bias and functional studies of WAG-2.

scholarly journals Comparative and phylogenetic analyses of the chloroplast genomes of species of Paeoniaceae

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Liwei Wu ◽  
Liping Nie ◽  
Qing Wang ◽  
Zhichao Xu ◽  
Yu Wang ◽  
...  
Keyword(s):  
Codon Usage ◽  
Phylogenetic Analyses ◽  
Ornamental Plants ◽  
Network Evolution ◽  
Rrna Genes ◽  
Trna Genes ◽  
Species Relationship ◽  
Variable Regions ◽  
Chloroplast Genomes ◽  
Usage Analysis

AbstractPlants belonging to family Paeoniaceae are not only economically important ornamental plants but also medicinal plants used as an important source of traditional Chinese medicine. Owing to the complex network evolution and polyploidy evolution of this family, its systematics and taxonomy are controversial and require a detailed investigation. In this study, three complete chloroplast genomes of sect. Paeonia, one of the sections of Paeonia, were sequenced and then analysed together with 16 other published chloroplast genomes of Paeoniaceae species. The total lengths of the chloroplast genomes of these species were 152,153–154,405 bp. A total of 82–87 protein-coding genes, 31–40 tRNA genes and 8 rRNA genes were annotated. Bioinformatics analysis revealed 61–74 simple sequence repeats (SSRs) in the chloroplast genomes, most of which have A/T base preference. Codon usage analysis showed that A/U-ending codons were more positive than C/G-ending codons, and a slight bias in codon usage was observed in these species. A comparative analysis of these 19 species of Paeoniaceae was then conducted. Fourteen highly variable regions were selected for species relationship study. Phylogenetic analysis revealed that the species of sect. Paeonia gathered in one branch and then divided into different small branches. P. lactiflora, P. anomala, P. anomala subsp. veitchii and P. mairei clustered together. P. intermedia was related to P. obovata and P. obovata subsp. willmottiae. P. emodi was the sister to all other species in the sect. Paeonia.

scholarly journals The Chloroplast Genomes Comparative Analysis of Taihangia Rupestris and Taihangia Rupestris Var. Ciliate, Two Endangered and Endemic Cliff Plants in Taihang Mountain of China

2021 ◽  
Author(s):  
Yan Zheng ◽  
Yuan Jiang ◽  
Yujing Miao ◽  
Zhan Feng ◽  
Min Zhang ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Codon Usage ◽  
Sustainable Use ◽  
Scientific Basis ◽  
Protein Coding ◽  
Protein Coding Genes ◽  
Repeat Sequences ◽  
Chloroplast Genomes ◽  
High Degree ◽  
Taihang Mountain

Abstract The Taihangia is a native endangered cliff species that grows in the Taihang Mountains in China. The cp genomes with a whole length of 155,558 bp and 155,479 bp for Taihangia rupestris and Taihangia rupestris var. rupestris. They have 131 genes in total, covering 79 protein-coding genes, 29 tRNA, and 4 rRNA. Analyses of codon usage, RNA-editing sites, repeat sequences, and comparison of cp genomes showed a high degree of conservation. Phylogenetic analysis indicated that the Taihangia are closed to the Geum. Taihangia genus was inferred to have originated at 0.2057 Mya, and Geum rupestre was inferred to have originated at 1.4431 Mya. Overall, the gene contents, gene arrangements, the types, and frequency of codon usage, repeat sequences, and SSRs are similar and highly conserved in the species of T. rupestris and T. rupestris var. ciliate. It is found that based on bioprospecting, T. rupestris and T. rupestris var. rupestris are potential medicinal resources. This study provides a scientific basis for the conservation and sustainable use of endangered medicinal resources..

Sign in / Sign up

Export Citation Format

Share Document