Search Results (250)

In the traditional classification system of the Lauraceae family based on morphology and anatomy, the phylogenetic position of the genus Sassafras has long been controversial. Chloroplast (cp) evolution of Sassafras has not yet been illuminated. In this study, we first sequenced and assembled the complete cp genomes of Sassafras, and conducted the comparative cp genomics, phylogenomics, and divergence time estimation of this ecological and economic important genus. The whole length of cp genomes of the 10 Sassafras ranged from 151,970 bp to 154,011 bp with typical quadripartite structure, conserved gene arrangements and contents. Variations in length of cp were observed in the inverted repeat regions (IRs) and a relatively high usage frequency of codons ending with T/A was detected. Four hypervariable intergenic regions (ccsA-ndhD, trnH-psbA, rps15-ycf1, and petA-psbJ) and 672 cp microsatellites were identified for Sassafras. Phylogenetic analysis based on 106 cp genomes from 30 genera within the Lauraceae family demonstrated that Sassafras constituted a monophyletic clade and grouped a sister branch with the Cinnamomum sect. Camphora within the tribe Cinnamomeae. Divergence time between S. albidum and its East Asian siblings was estimated at the Middle Miocene (16.98 Mya), S. tzumu diverged from S. randaiense at the Pleistocene epoch (3.63 Mya). Combined with fossil evidence, our results further revealed the crucial role of the Bering Land Bridge and glacial refugia in the speciation and differentiation of Sassafras. Overall, our study clarified the evolution pattern of Sassafras cp genomes and elucidated the phylogenetic position and divergence time framework of Sassafras. Full article

Background/Objectives: The gene pool of the Apennine wolf is affected by admixture with domestic variants due to anthropogenic hybridisation with dogs. Genetic monitoring at the population level involves assessing the extent of admixture in single individuals, ranging from pure wolves to recent hybrids or wolf backcrosses, through the analysis of nuclear and mitochondrial DNA (mtDNA) markers. Although individually non-diagnostic, mtDNA is nevertheless essential for completing the final diagnosis of genetic admixture. Typically, the identification of wolf mtDNA haplotypes is carried out via sequencing of coding genes and non-coding DNA stretches. Our objective was to develop a fast real-time PCR assay to detect the mtDNA haplotypes that occur exclusively in the Apennine wolf population, as a valuable alternative to the demanding sequence-based typing. Methods: We validated a qualitative duplex real-time PCR that exploits the combined presence of diagnostic point mutations in two mtDNA segments, the NDH-4 gene and the control region, and is performed in a single-tube step through TaqMan-MGB chemistry. The aim was to detect mtDNA multi-fragment haplotypes that are exclusive to the Apennine wolf, bypassing sequencing. Results: Basic validation of 149 field samples, consisting of pure Apennine wolves, dogs, wolf × dog hybrids, and Dinaric wolves, showed that the assay is highly specific and sensitive, with genomic DNA amounts as low as 10⁻⁵ ng still producing positive results. It also proved high repeatability and reproducibility, thereby enabling reliable high-throughput testing. Conclusions: The results indicate that the assay presented here provides a valuable alternative method to the time- and cost-consuming sequencing procedure to reliably diagnose the maternal lineage of the still-threatened Apennine wolf, and it covers a wide range of applications, from scientific research to conservation, diagnostics, and forensics. Full article

The number of Fritillaria species native to the Alps has long been debated, and observational biases due to the short flowering periods and the scattered distributions of endemic Fritillaria populations along the mountain range have probably made the task of botanists more complicated. Moreover, previous phylogenetic studies in Fritillaria have considered alpine taxa only marginally. To test species boundaries within the F. tubaeformis species complex and to study their phylogenetic relationships, intra- and inter-specific genetic variability of sixteen samples belonging to four Fritillaria species was carried out in different localities of the Maritime and Ligurian Alps, with extensions to the rest of the Alpine arc. The combined use of five plastid DNA markers (matK, ndhF, rpl16, rpoC1, and petA-psbJ) and nrITS showed that F. tubaeformis and F. burnatii are phylogenetically independent taxa, fully confirming morphological and morphometric divergences and, that F. burnatii is not related phylogenetically to the central European F. meleagris. Our phylogenetic study also supports the separation of F. tubaeformis from F. moggridgei, pointing to environment/ecological constraints or reproductive barriers as possible causes of their distinct evolutionary status. Our analysis also showed that the mountain endemic F. involucrata is not closely related to F. tubaeformis, contrasting with previous studies. The phylogenetic analysis of the nrITS region supports a close relationship between F. burnatii and F. moggridgei, but with low statistical support. Full article

Complete chloroplast genome sequences are widely used in the analyses of phylogenetic relationships among angiosperms. As a species-rich genus, species diversity centers of Saxifraga L. include mountainous regions of Eurasia, such as the Alps and the Qinghai–Tibetan Plateau (QTP) sensu lato. However, to date, datasets of chloroplast genomes of Saxifraga have been concentrated on the QTP species; those from European Alps are largely unavailable, which hinders comprehensively comparative and evolutionary analyses of chloroplast genomes in this genus. Here, complete chloroplast genomes of 19 Saxifraga species were de novo sequenced, assembled and annotated, and of these 15 species from Alps were reported for the first time. Subsequent comparative analysis and phylogenetic reconstruction were also conducted. Chloroplast genome length of the 19 Saxifraga species range from 149,217 bp to 152,282 bp with a typical quadripartite structure. All individual chloroplast genome included in this study contains 113 unique genes, including 79 protein-coding genes, four rRNAs and 30 tRNAs. The IR boundaries keep relatively conserved with minor expansion in S. consanguinea. mVISTA analysis and identification of polymorphic loci for molecular markers shows that six intergenic regions (ndhC-trnV, psbE-petL, rpl32-trnL, rps16-trnQ, trnF-ndhJ, trnS-trnG) can be selected as the potential DNA barcodes. A total of 1204 SSRs, 433 tandem repeats and 534 Large sequence repeats were identified in the 19 Saxifraga chloroplast genomes. The codon usage analysis revealed that Saxifraga chloroplast genome codon prefers to end in A/T. Phylogenetic reconstruction of 33 species (31 Saxifraga species included) based on 75 common protein coding genes received high bootstrap support values for nearly all identified nodes, and revealed a tree topology similar to previous studies. Full article

Phylogenetic relationships within the subtribe Arethusinae (Arethuseae: Epidendroideae: Orchidaceae) remain unresolved, with particular uncertainty surrounding the phylogenetic positions of Anthogonium gracile and Eleorchis japonica. The monophyly of this subtribe remains contentious, making it one of the challenging taxa in Orchidaceae phylogenetics. In this study, we sequenced and analyzed the complete plastome sequences of A. gracile and E. japonica for the first time, aiming to elucidate their plastome characteristics and phylogenetic relationships. Both plastomes exhibited a conserved quadripartite structure, with 158,358 bp in A. gracile and 152,432 bp in E. japonica, and GC contents of 37.1% and 37.3%, respectively. Comparative analyses revealed strong structural conservation, but notable gene losses: E. japonica lacked seven ndh genes (ndhC/D/F/G/H/I/K), whereas A. gracile retained a complete ndh gene set. Repetitive sequence analysis identified an abundance of simple sequence repeats (68 and 77), tandem repeats (43 and 30), and long repeats (35 and 40). Codon usage displayed a bias toward the A/U termination, with leucine and isoleucine being the most frequent. Selection pressure analysis indicated that 68 protein-coding genes underwent purifying selection (Ka/Ks < 1), suggesting evolutionary conservation of plastome protein-coding genes. Nucleotide diversity analysis highlighted six hypervariable regions (rps8-rpl14, rps16-trnQ^UUG, psbB-psbT, trnT^UGU-trnL^UAA, trnF^GAA-ndhJ, and ycf1), suggesting their potential as molecular markers. Phylogenomic reconstruction, using complete plastome sequences, (ML, MP, and BI) indicated that Arethusinae was non-monophyletic. A. gracile formed a sister relationship with Mengzia foliosa and E. japonica, whereas Arundina graminifolia exhibited a sister relationship with Coelogyninae members. These results shed new light on the plastome characteristics and phylogenetic relationships of Arethusinae. Full article

Background/Objectives: Mango, which is known as the “King of Tropical Fruits”, is an evergreen plant belonging to the Anacardiaceae family. It belongs to the genus Mangifera, which comprises 69 species of plants found in tropical and subtropical regions, including India, Indonesia, the Malay Peninsula, Thailand, and South China. However, research on the structural information of complete chloroplast genomes of Mangifera is limited. Methods: The rapid advancement of high-throughput sequencing technology enables the acquisition of the entire chloroplast (cp) genome sequence, providing a molecular foundation for phylogenetic research. This work sequenced the chloroplast genomes of six Mangifera samples, performed a comparative analysis of the cp genomes, and investigated the evolutionary relationships within the Mangifera genus. Results: All six Mangifera samples showed a single circular molecule with a quadripartite structure, ranging from 157,604 bp to 158,889 bp in length. The number of RNA editing sites ranged from 60 to 61, with ndhB exhibiting the highest number of RNA editing sites across all species. Seven genes—namely, atpB, cemA, clpP, ndhD, petB, petD, and ycf15—exhibited a Ka/Ks value > 1, suggesting they may be under positive selection. Phylogenetic analysis revealed that Mangifera siamensis showed a close relationship between Mangifera indica and Mangifera sylvatica. Conclusions: Our comprehensive analysis of the whole cp genomes of the five Mangifera species offers significant insights regarding their phylogenetic reconstruction. Moreover, it elucidates the evolutionary processes of the cp genome within the Mangifera genus. Full article

Background: Artemisia is a large and complex genus comprising about 500 species. Currently, only a limited number of plastomes (the chloroplast genome) of Artemisia are available. Their structures have not been comparatively analyzed, and a phylogenetic backbone based on plastome-scale data is still lacking. This situation has greatly hindered our understanding of the plastome variation patterns and infra-generic relationships of the genus. Methods: We newly sequenced 34 Artemisia plastomes representing 30 species and three varieties. Combining this with previously published plastomes, we comparatively analyzed their structure and constructed phylogenetic relationships using the protein-coding sequences (CDS) of plastomes. Results: Our analyses indicated that the Artemisia plastomes are conserved in terms of their structure, GC content, gene number, and order. The sequence divergence is higher in the LSC and SSC regions than in the IR regions. Three protein-coding genes and four non-coding regions, i.e., accD, petG, ycf1, rpoC1-rpoC2, rpoC2-rps2, trnG(UCC)-trnfM(CAU), and ndhG-ndhI, were highly diverse and could be chosen as candidates of DNA barcodes. Phylogenetic trees were divided into several clades, and all four main subgenera were not monophyletic. Additionally, the phylogenetic position of A. stracheyi is still controversial. Conclusions: Plastomes can provide important information for phylogenetic constructions. This study provides insights into the infra-generic relationships within Artemisia and also lays a foundation for future evolutionary studies of this genus. Full article

Background/Objectives: In South China, Lithocarpus species dominate mixed evergreen broadleaf forests, forming symbiotic relationships with ectomycorrhizal fungi and serving as food resources for diverse fauna, including frugivorous birds and mammals. The limited understanding of chloroplast genomes in this genus restricts our insights into its species diversity. This study investigates the chloroplast genome (cp genome) sequences from seven Lithocarpus species, aims to elucidate their structural variation, evolutionary relationships, and functional gene content to provide effective support for future genetic conservation and breeding efforts. Methods: We isolated total DNA from fresh leaves and sequenced the complete cp genomes of these samples. To develop a genomic resource and clarify the evolutionary relationships within Lithocarpus species, comparative chloroplast genome studies and phylogenetic investigations were performed. Results: All studied species exhibited a conserved quadripartite chloroplast genome structure, with sizes ranging from 161,495 to 163,880 bp. Genome annotation revealed 130 functional genes and a GC content of 36.72–37.76%. Codon usage analysis showed a predominance of leucine-encoding codons. Our analysis identified 322 simple sequence repeats (SSRs), which were predominantly palindromic in structure (82.3%). All eight species exhibited the same 19 SSR categories in similar proportions. Eight highly variable regions (ndhF, ycf1, trnS-trnG-exon1, trnk(exon1)-rps16(exon2), rps16(exon2), rbcL-accD, and ccsA-ndh) have been identified, which could be valuable as molecular markers in future studies on the population genetics and phylogeography of this genus. The phylogeny tree provided critical insights into the evolutionary trajectory of Fagaceae, suggesting that Lithocarpus was strongly supported as monophyletic, while Quercus was inferred to be polyphyletic, showing a significant cytonuclear discrepancy. Conclusions: We characterized and compared the chloroplast genome features across eight Lithocarpus species, followed by comprehensive phylogenetic analyses. These findings provide critical insights for resolving taxonomic uncertainties and advancing systematic research in this genus. Full article

Hip joint reconstruction is often necessary for children and adolescents with conditions like developmental dysplasia of the hip (DDH), neurogenic dislocation of the hip (NDH), or Legg–Calvé–Perthes disease (LCPD) when non-surgical treatments are ineffective. Background: Post-operative immobilization after hip reconstruction in children is crucial to promote proper healing and reduce the risk of complications. While spica casting has been the traditional method, it can lead to various issues. Foam splinting has emerged as an alternative approach. This study aimed to compare the effectiveness and satisfaction of the patient and the caregivers of spica casting and foam splinting after pelvic osteotomies in young patients with DDH, NDH, and LCPD. Methods: A prospective randomized clinical trial included patients aged 3 to 16 undergoing pelvic reconstruction (iliac and proximal femoral osteotomy, open reduction, and soft tissue procedures). Participants were randomized into two groups: one receiving spica casts and the other foam splints, both for a six-week period post-surgery. Quality of life (QOL) assessments like CPCHILD, SF-36, and EQ-5D were conducted using various scores to measure patient and caregiver satisfaction preoperative and at six and twelve weeks postoperative. The surgical techniques were consistent across both groups. Results: The study included 34 patients, with one excluded due to non-adherence. The spica cast group experienced statistically significant declines in QOL scores, while the foam splint group showed decreases that were not statistically significant. Complications were reported in 11 patients, with a higher prevalence in the spica cast group. Conclusions: The foam splint group demonstrated superior satisfaction levels and fewer complications, which leads to the conclusion that foam splinting should be the preferred option to spica casting for post-operative immobilization in these cases. Full article

New Caledonia is a biodiversity hotspot with flora closely related to that of Australia and has received considerable attention. Endiandra (Cryptocaryeae; Lauraceae) is distributed from tropical Asia to Oceania, including New Caledonia, with northeastern Australia and New Guinea as diversity centers, but the genus in New Caledonia remains understudied. Here, four species of Endiandra native to New Caledonia were sequenced, and their complete plastome sequences were analyzed. A plastome-based phylogenomic tree of Cryptocaryeae was reconstructed, and divergence times were estimated. The phylogenomic tree supports the monophyly of Endiandra. Interestingly, the species of Endiandra from New Caledonia were grouped into two separate subclades, with one subclade including three species and the other subclade containing only one species. The stem and crown ages of the first subclade were 33.18 Ma and 14.5 Ma, respectively, and the second subclade diverged by approximately 10.36 Ma. The structural characteristics of the newly sequenced plastomes were compared with those of Beilschmiedia species from different continents. The results indicate that the plastome sequences of the four species of Endiandra are longer than those of Beilschmiedia. Additionally, Endiandra has more simple sequence repeats (SSRs) than Beilschmiedia, though the difference is slight. The Guanine-Cytosine (GC) content of Endiandra was lower than that of Beilschmiedia. Five highly variable regions were identified, including matK-rps16, ycf1, petA-psbJ, petN-psbM, and ndhF. The Endiandra species in New Caledonia originated through long-distance dispersal followed by local divergence, rather than vicariance. Additionally, we identified at least two instances of floristic exchange between New Caledonia and Australia. Our study provides further evidence for understanding the biogeographic history between these two regions. Full article

In the present study, the sequencing and analysis of the complete chloroplast genome of Cleome houtteana and its comparison with related species in the Cleomaceae family were carried out. The genome spans 157,714 base pairs (bp) and follows the typical chloroplast structure, consisting of a large single-copy (LSC) region (87,506 bp), a small single-copy (SSC) region (18,598 bp), and two inverted repeats (IRs) (25,805 bp each). We identified a total of 129 genes, including 84 protein-coding genes, 8 ribosomal RNA (rRNA) genes, and 37 transfer RNA (tRNA) genes. Our analysis of simple sequence repeats (SSRs) and repetitive elements revealed 91 SSRs, with a high number of A/T-rich mononucleotide repeats, which are common in chloroplast genomes. We also observed forward, palindromic, and tandem repeats, which are known to play roles in genome stability and evolution. When comparing C. houtteana with its relatives, we identified several highly variable regions, including ycf1, ycf2, and trnH–psbA, marking them as propitious molecular markers for the identification of species as well as phylogenetic studies. We examined the inverted repeat (IR) boundaries and found minor shifts in comparison to the other species, particularly in the ycf1 gene region, which is a known hotspot for evolutionary changes. Additionally, our analysis of selective pressures (Ka/Ks ratios) showed that most genes are under strong purifying selection, preserving their essential functions. A sliding window analysis of nucleotide diversity (Pi) identified several regions with high variability, such as trnH–psbA, ycf1, ndhI-ndhG, and trnL-ndhF, highlighting their potential for use in evolutionary and population studies. Finally, our phylogenetic analysis, using complete chloroplast genomes from species within Cleomaceae, Brassicaceae, and Capparaceae, confirmed that C. houtteana belongs within the Cleomaceae family. It showed a close evolutionary relationship with Tarenaya hassleriana and Sieruela rutidosperma, supporting previous taxonomic classifications. The findings from the current research offer invaluable insights regarding genomic structure, evolutionary adaptations, and phylogenetic relationships of C. houtteana, providing a foundation for future research on species evolution, taxonomy, and conservation within the Cleomaceae family. Full article

Banisteriopsis is a genus in the Malpighiaceae family with 61 species, notable for including ritualistic taxa such as B. caapi (Spruce ex Griseb.) C.V. Morton, one of the main components of Ayahuasca tea. We analyzed 38 Banisteriopsis species, representing more than 60% of the genus, to investigate its geographical origin, diversification period, and colonization routes in the Neotropics. Plastid genes (matK, ndhF, and rbcL) and nuclear regions (ETS, ITS, and PHYC) were used in our analyses. Divergence time analyses were performed using Bayesian inference with a relaxed molecular clock and ancestral area reconstruction. Our results show that Banisteriopsis originated in the Miocene approximately 22 million years ago, and its diversification coincides with the expansion of dry areas in South America. Banisteriopsis began colonizing the Cerrado earlier than most other plants, and the history of the genus reveals that the biome served as a source of species for Neotropical rainforests. Our results also indicate a probable ancient origin for B. caapi, with no evidence of human manipulation in its diversification, and they reinforce archaeological evidence of a millennia-old exchange of uses among Amazonian peoples. Full article

In order to detail the antiplasmodial effects of quinones (Q) and nitroaromatic compounds (ArNO₂), we investigated their reduction mechanism by Plasmodium falciparum flavoenzyme type II NADH:ubiquinone oxidoreductase (PfNDH2). The reactivity of Q and ArNO₂ (n = 29) follows a common trend and exhibits a parabolic dependence on their single-electron reduction potential ($E_7^1$), albeit with significantly scattered data. The reactivity of quinones with similar $E_7^1$ values increases with their lipophilicity. Quinones are reduced by PfNDH2 in a two-electron way, but ArNO₂ are reduced in a single-electron way. The inhibition studies using NAD⁺ and ADP-ribose showed that quinones oxidize the complexes of reduced enzyme with NADH and NAD⁺. This suggests that, as in the case of other NDH2s, quinones and the nicotinamide ring of NAD(H) bind at separate sites. A scheme of PfNDH2 catalysis is proposed, consistent with both the observed ‘ping-pong’ mechanism and the presence of two substrate binding sites. Molecular docking showed that Q and ArNO₂ bind in a similar manner and that lipophilic quinones have a higher affinity for the binding site. One may expect that PfNDH2 can be partially responsible for the previously observed enhanced antiplasmodial activity of aziridinylbenzoquinones caused by their two-electron reduction, as well as for the redox cycling and oxidative stress-type action of ArNO₂. Full article

As the most diverse genus of Salicaceae, Salix is primarily distributed in the temperate zone of the Northern Hemisphere, encompassing 350–500 species worldwide. The genus’s evolutionary history is complex due to significant genetic differentiation. Chloroplast genes, being highly conserved, serve as effective tools for studying uniparental inheritance and evolution. In this study, we sequenced and assembled the chloroplast genomes of five representative Salix species. Phylogenetic relationships were constructed using chloroplast genome data, and structural differences among lineages were compared. These Salix chloroplast genomes exhibited a typical quadripartite structure, with lengths ranging from 154,444 to 155,725 bp. We successfully annotated 131 genes, including 88 protein-coding genes, 35 tRNA genes, and 8 rRNA genes. Clade I showed higher variability in the SSC region, identifying five highly variable regions: petA-psbJ, rps16-rps3, ndhD, ccsA-ndhD, and ndhG-ndhI. Two rapidly evolving genes, ndhI and ycf4, were also identified. The total length of insertions and deletions (InDels) in Clade I was 1046 bp. Clade II exhibited greater variability in the LSC region, with four highly variable regions being identified: trnK-trnQ, ndhC-trnV, trnV, and psdE-petL. Four rapidly evolving genes—infA, rpoC1, rps18, and ycf1—were identified. The total length of InDels in Clade II was 1282 bp. Therefore, this study elucidated the chloroplast genome evolution across different Salix lineages, thereby providing deeper insights into intrageneric phylogenetic relationships. Full article

Camphora Fabr. is a genus in the family Lauraceae, comprising over 20 tropical and subtropical tree species. Since the genera Camphora and Cinnamomum Schaeff. were described, there has been a long-lasting controversy regarding the phylogenetic relationships among taxa in both genera. In particular, phylogenetic inferences derived from plastid data remain debated, with varying hypotheses proposed and occasional disputes concerning the monophyly of Camphora taxa. To further investigate the relationships, We analyzed plastomes and nuclear ribosomal cistron sequences (nrDNA) of 22 Camphora taxa, 15 Cinnamomum taxa, and 13 representative taxa of related genera. The Camphora plastomes range from 152,745 to 154,190 bp, with a GC content of 39.1% to 39.2%. A total of 128 genes were identified in the Camphora plastomes, including 84 protein-coding genes, 8 rRNA genes, and 36 tRNA genes. A total of 1130 SSR loci were detected from plastomes of Camphora, and A/T base repeats looked like the most common. Comparative analyses revealed that the plastomes of Camphora exhibit high similarity in overall structure. The loci ycf1, ycf2, trnK (UUU), psbJ-psbL, and ccsA-ndhD were identified as candidate DNA barcodes for these taxa. Plastome phylogenetic analysis revealed that Camphora is not monophyletic, whereas the nrDNA dataset supported the monophyly of Camphora. We propose that intergeneric hybridization may underlie the observed discordance between plastid and nuclear data in Camphora, and we recommend enhanced taxonomic sampling and precise species identification to improve phylogenetic resolution and accuracy. Full article