Search Results (99)

Background: Rosa L. is an economically significant genus with species that are notable for their rich content of phenolic compounds. Despite its importance, the taxonomy of Rosa remains complex and unresolved. Methods: We sequenced, assembled, and performed comparative analyses of the complete plastomes of four Rosa species: R. acicularis, R. iliensis, R. laxa, and R. spinosissima. In addition to the plastome, we sequenced the nuclear ribosomal internal transcribed spacer (ITS). Results: Plastomes ranged in size from 157,148 bp (R. iliensis) to 157,346 bp (R. laxa). In each plastome, 136 genes were annotated, comprising 90 protein-coding, 38 tRNA, and eight rRNA genes. A total of 905 SSRs were identified, ranging from 224 (R. acicularis) to 229 in R. spinosissima. Nine highly variable regions were detected, including two coding genes (rps16 and ycf1) and seven intergenic spacers (ycf3-trnS(GGA), trnT(UGU)-trnL(UAA), rpl14-rpl16, trnR(UCU)-atpA, trnD(GUC), trnG(UCC)-trnfM(CAU), and psbE-petL). Maximum Likelihood (ML) phylogenetic analyses based on the complete plastome and ycf1 gene datasets consistently resolved the Rosa species into three major clades, with strong bootstrap support. In contrast, the ML tree based on ITS resolved species into four clades but showed lower bootstrap values, indicating reduced resolution compared to plastid datasets. Conclusions: Our findings underscore the value of plastome data in resolving phylogenetic relationships within the genus Rosa. Full article

The molecular identification of valuable genotypes is an important problem of germplasm management. In this study, we evaluated the potential of 11 universal primer pairs for the DNA barcoding of locally derived cultivars of subtropical crops (actinidia, feijoa, citrus, and tea). A total of 47 accessions (elite cultivars, forms, and breeding lines) of these four genera were included in the study. The efficiency of the following universal primers was assessed using Sanger sequencing: ITS-p5/ITS-u4, ITS-p5/ITS-u2, ITS-p3/ITS-u4, 23S,4.5S&5S, 16S, petB/petD, rpl23/rpl2.l, rpl2 intron, rpoC1 intron, trnK intron, and trnE-UUC/trnT-GUU. Among these primers, trnE-UUC/trnT-GUU showed greater intraspecific polymorphisms, while rpl2 intron and 16S displayed the lowest polymorphism levels in all crops. In addition, the 23S,4.5S & 5S, and rpoC1 intron were efficient for intraspecific analysis of tea and actinidia species. Using five efficient chloroplast primers, a total of 22/6 SNPs/InDels were observed in tea accessions, 45/17 SNPs/InDels in actinidia, 23/3 SNPs/InDels in mandarins, and 5/4 SNPs/InDels in feijoa. These results will be useful for the further development of DNA barcodes of related accessions. Full article

Immunotherapy has emerged as a key modality in cancer treatment, yet its effectiveness varies significantly among patients, often due to the metabolic stress imposed by the tumor microenvironment. Hypoxia, a major factor in the tumor microenvironment, results from the high metabolic rate of tumor cells and inadequate vascularization, impairing immune cells’ function and potentially influencing gene expression profiles. Despite the widespread use of quantitative real-time PCR in immunological studies, to the best of our knowledge, data on reference gene stability in human peripheral blood mononuclear cells under hypoxic conditions is limited. In our study, we assessed the expression stability of commonly used reference genes (S18, HPRT, IPO8, RPL13A, SDHA, PPIA, and UBE2D2) in both non-stimulated and CD3/CD28-activated peripheral blood mononuclear cells cultured under normoxic, hypoxic (1% O₂), and chemically induced hypoxic conditions for 24 h. Analysis using four different algorithms—delta Ct, geNorm, NormFinder, and BestKeeper—identified RPL13A, S18, and SDHA as the most suitable reference genes for human peripheral blood mononuclear cells under hypoxic conditions. In contrast, IPO8 and PPIA were found to be the least suitable housekeeping genes. The study provides essential insights into the stability of reference genes in peripheral blood mononuclear cells under hypoxic conditions, a critical but understudied aspect of immunological research. Given the significant impact of hypoxia on T cell metabolism and function in the tumor microenvironment, selecting reliable reference genes is crucial for accurate gene expression analysis. Our findings will be valuable for future studies investigating hypoxia-driven metabolic reprogramming in immune cells, ultimately contributing to a better understanding of T cell responses in cancer immunotherapy. Full article

Rhododendron purdomii Rehder & E. H. Wilson (Ericaceae) is a threatened ornamental and medicinal shrub or small tree species primarily distributed in the Qinling-Daba Mountains of Central China. To facilitate its conservation and utilization, the complete chloroplast genome of Rh. purdomii was sequenced, assembled, and characterized. The cp genome exhibited a typical quadripartite structure with a total length of 208,062 bp, comprising a large single copy (LSC) region of 110,618 bp, a small single copy (SSC) region of 2606 bp, and two inverted repeat (IR) regions of 47,419 bp each. The overall GC content was 35.81%. The genome contained 146 genes, including 96 protein-coding genes, 42 transfer RNA genes, and 8 ribosomal RNA genes. Structure analysis identified 67,354 codons, 96 long repetitive sequences, and 171 simple sequence repeats. Comparative genomic analysis across Rhododendron species revealed hypervariable coding regions (accD, rps9) and non-coding regions (trnK-UUU-ycf3, trnI-CAU-rpoB, trnT-GGU-accD, rpoA-psbL, rpl20-trnC-GCA, trnI-CAU-rrn16, and trnI-CAU-rps16), which may serve as potential molecular markers for genetic identification. Phylogenetic reconstruction confirmed the monophyly of Rhododendron species and highlighted a close relationship between Rh. purdomii and Rh. henanense subsp. lingbaoense. These results provide essential genomic resources for advancing taxonomic, evolutionary, conservation, and breeding studies of Rh. purdomii and other species within the genus Rhododendron. Full article

Salvia, a medicinally and economically important genus, is widely used in traditional medicine, agriculture, and horticulture. This study compares the chloroplast genomes of eight East Asian Salvia species to assess genetic diversity, structural features, and evolutionary relationships. Complete chloroplast genomes were sequenced, annotated, and analyzed for gene content, codon usage, and repetitive sequences. Phylogenetic relationships were reconstructed using Maximum Likelihood, Maximum Parsimony and Bayesian inference. The genomes exhibited a conserved quadripartite structure (151,081–152,678 bp, GC content 37.9–38.1%), containing 114 unique genes with consistent arrangement. Codon usage favored A/T endings, with leucine (Leu) most frequent and cysteine (Cys) least. We identified 281 long sequence repeats (LSRs) and 345 simple sequence repeats (SSRs), mostly in non-coding regions. Comparative analysis revealed five hypervariable regions (trnH-psbA, rbcL-accD, petA-psbJ, rpl32-trnL, ycf1) as potential molecular markers. Phylogenetic analysis confirmed the monophyly of East Asian Salvia, dividing them into five clades, with Sect. Sonchifoliae basal. While G1, G3, and G8 were monophyletic, G5 and G6 were paraphyletic, and the G7-G8 relationship challenged traditional classifications. The genomic evidence provides crucial insights for resolving long-standing taxonomic uncertainties and refining the classification system of Salvia. These findings suggest a complex evolutionary history involving hybridization and incomplete lineage sorting, providing valuable genomic insights for Salvia phylogeny, taxonomy, and conservation. 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

Runs of homozygosity (ROHs) are continuous homozygous segments of genomes that can be used to infer the historical development of the population. ROH studies allow us to analyze the genetic structure of a population and identify signs of selection. The present study searched for ROH regions in the Faverolle chicken breed. DNA samples from modern individuals and museum Faverolle specimens were obtained and sent for whole-genome sequencing (WGS) with 30× coverage. The results were aligned to the reference genome and subjected to additional filtering. ROH segments were then analyzed using PLINK 1.9. As a result, 10 regions on GGA1, 2, 3, 4, and 13 were identified. A total of 19 genes associated with fat deposition and lipid metabolism (GBE1, CACNA2D1, STON1, PPP1R21, RPL21L1, ATP6V0E1, CREBRF, NKX2-2, COMMD1), fertility (LHCGR, GTF2A1L, SAMD5), muscle development and body weight (VGLL3, CACNA2D1, FOXN2, ERGIC1, RPL26L1), the shape and relative size of the skeleton (FAT4), and autophagy and apoptosis (BNIP1) were found. Developmental protein genes (PAX1, NKX2-2, NKX2-4, NKX2-5) formed a separate cluster. Probably, selection for the preservation of high flavor characteristics contributed to the consolidation of these ROH regions. The present research enhances our knowledge on the Faverolle breed’s genome and pinpoints their ROH segments that are also specific «selection traces». Full article

Breast cancer (BC) is among the most prevalent malignancies and remains the leading cause of cancer-related mortality in women worldwide. While prior studies have highlighted the associations between insulin resistance (IR) and both tumorigenesis and cancer progression, the prognostic relevance of IR in BC has not been fully elucidated. In this study, we employed a suite of machine learning algorithms and statistical methods to construct a robust prognostic model for BC based on insulin resistance-related genes (IRGs). The model’s prognostic value was subsequently validated in four independent validate cohorts, including METABRIC and three GSE datasets. The resulting IR signature, comprising seven hub IRGs (LIFR, EZR, TBC1D4, NSF, RPL5, SAA1, and PGK1), demonstrated high predictive power for overall survival (OS) across public datasets. Notably, a lower insulin resistance risk score (IRRS) was significantly associated with more favorable clinical outcomes, including enhanced responses to neoadjuvant therapy. Based on single-cell RNA sequencing data, we found that the hub genes were more enriched in T cells, B cells, and epithelial cells. Furthermore, we used machine learning methods to perform feature selection and reduction, which generated a clinically applicable scoring system consisting of the seven hub genes for predicting clinical outcomes in BC patients. This novel IR-based prognostic signature offers a valuable tool for stratifying BC patients by risk and tailoring personalized therapeutic strategies, thus enhancing precision oncology in breast cancer care. Full article

The chloroplast genome, as an important evolutionary marker, can provide a new breakthrough direction for the population evolution of plant species. Actinidia deliciosa represents one of the most economically significant and widely cultivated fruit species in the genus Actinidia. In this study, we sequenced and analyzed the complete chloroplast genomes of seven cultivars of Actinidia. deliciosa to detect the structural variation and population evolutionary characteristics. The total genome size ranged from 156,404 bp (A. deliciosa cv. Hayward) to 156,495 bp (A. deliciosa cv. Yate). A total of 321 simple sequence repeats (SSRs) and 1335 repetitive sequences were identified. Large-scale repeat sequences may facilitate indels and substitutions, molecular variations in A. deliciosa varieties' chloroplast genomes. Additionally, four polymorphic chloroplast DNA loci (atpF-atpH, atpH-atpI, atpB, and accD) were detected, which could potentially provide useful molecular genetic markers for further population genetics studies within A. deliciosa varieties. Site-specific selection analysis revealed that six genes (atpA, rps3, rps7, rpl22, rbcL, and ycf2) underwent protein sequence evolution. These genes may have played key roles in the adaptation of A. deliciosa to various environments. The population evolutionary analysis suggested that A. deliciosa cultivars were clustered into an individual evolutionary branch with moderate-to-high support values. These results provided a foundational genomic resource that will be a major contribution to future studies of population genetics, adaptive evolution, and genetic improvement in Actinidia. Full article

Karyopherins, carrier proteins that recognize particular cargo protein patterns known as nuclear localization signals (NLSs), mediate the nuclear translocation of big proteins. In order to better understand the process of nuclear transport of proteins and create the groundwork for the development of innovative treatments that specifically target importins, it is imperative to clarify the intricate interactions between nuclear transporters and their cargo proteins. Until recently, very few NLSs have been documented. In the current work, an in silico method was used to identify NLSs for importin 8. It was determined that the sequence RRKLPVGRS serves as a recognition motif for importin 8 binding a karyopherin that is involved in the nuclear transportation of several important proteins like AGOs, SMADs, RPL23A, and TFE3. The sequence was validated in vitro in the breast cancer cell line T47D. This work subscribes to the effort to clarify the intricate relationships between nuclear transporters and their cargo proteins, in order to better understand the mechanism of nuclear transport of proteins and lay the groundwork for the development of novel therapeutics that target particular importins and have an immediate translational impact. Full article

Oxazolidinones, novel synthetic antibacterials, inhibit protein biosynthesis and show potent activity against Gram-positive bacteria, including Mycobacterium tuberculosis (MTB). In this study, we aimed to compare the in vitro activity of linezolid (LZD) and four oxazolidinones, including tedizolid (TZD), contezolid (CZD), sutezolid (SZD), and delpazolid (DZD), against multidrug-resistant tuberculosis (MDR-TB) and pre-extensively drug-resistant tuberculosis (pre-XDR-TB) isolates from Hainan. We established their epidemiological cut-off values (ECOFFs) using ECOFFinder software and analyzed mutations in rrl (23S rRNA), rplC, rplD, mce3R, tsnR, Rv0545c, Rv0930, Rv3331, and Rv0890c genes to uncover potential mechanisms of oxazolidinone resistance. This study included 177 MTB isolates, comprising 67 MDR and 110 pre-XDR-TB isolates. Overall, SZD exhibited the strongest antibacterial activity against clinical MTB isolates, followed by TZD and LZD, with CZD and DZD showing equivalent but weaker activity (SZD_MIC50 = TZD_MIC50 < LZD_MIC50 < CZD_MIC50 = DZD_MIC50; SZD_MIC90 < TZD_MIC90 = LZD_MIC90 < CZD_MIC90 = DZD_MIC90). Significant differences in MIC distribution were observed for TZD (p < 0.0001), CZD (p < 0.01), SZD (p < 0.0001), and DZD (p < 0.0001) compared to LZD but not between MDR-TB and pre-XDR-TB isolates. We propose the following ECOFFs: SZD, 0.5 µg/mL; LZD, TZD, and CZD, 1.0 µg/mL; DZD, 2.0 µg/mL. No statistically significant differences in resistance rates were observed among these five drugs (p > 0.05). We found that eight MTB isolates (4.52% [8/177]) resisted these five oxazolidinones. Among these, only one isolate, M26, showed an amino acid substitution (Arg79His) in the protein encoded by the rplD gene, which conferred cross-resistance to TZD and CZD. Three distinct mutations were identified in the mce3R gene; notably, isolate P604 displayed two insertions that contributed to resistance against all five oxazolidinones. However, no significant correlation was observed between mutations in the rrl, rplC, rplD, mce3R, tsnR, Rv0545c, Rv0930, Rv3331, and Rv0890c genes with oxazolidinone resistance in the clinical MTB isolates tested. In summary, this study provides the first report on the resistance of MTB in Hainan to the five oxazolidinones (LZD, TZD, CZD, SZD, and DZD). In vitro susceptibility testing indicated that SZD exhibited the strongest antibacterial activity, followed by TZD and LZD, while CZD and DZD demonstrated comparable but weaker effectiveness. Mutations in rplD and mce3R were discovered, but further research is needed to clarify their role in conferring oxazolidinone resistance in MTB. Full article

Brownlowia tersa and Brownlowia argentata are two true mangroves in the genus Brownlowia in Malvaceae, and they are a near-threatened and a data-deficient species, respectively. However, the genomic resources of Brownlowia have not been reported for studying their phylogeny and evolution. Here, we report the chloroplast genomes of B. tersa and B. argentata based on stLFR data that were 159,478 and 159,510 base pairs in length, respectively. Both chloroplast genomes contain 110 unique genes and one infA pseudogene. Sixty-eight RNA-editing sites were detected in 26 genes in B. argentata. A comparative analysis with related species showed similar genome sizes, genome structures, and gene contents as well as high sequence divergence in non-coding regions. Abundant SSRs and dispersed repeats were identified. Five hotspots, psbI-trnS, trnR-atpA, petD-rpoA, rpl16-rps3, and trnN-ndhF, were detected among four species in Brownlowioideae. One hotspot, rps14-psaB, was observed in the two Brownlowia species. Additionally, phylogenetic analysis supported that the Brownlowia species has a close relationship with Pentace triptera. Moreover, rpoC2 was a candidate gene for adaptive evolution in the Brownlowia species compared to P. triptera. Thus, these chloroplast genomes present valuable genomic resources for further evolutionary and phylogenetic studies of mangroves and plant species in Malvaceae. Full article

Callitriche species are capable of purifying water, promoting wetland restoration, and providing natural shelters. Moreover, they can be utilized as horticultural plants for landscape greening. However, due to the threats of climate change and environmental degradation, some species within this genus have been listed as endangered. This study utilizes chloroplast genome analysis to provide molecular evidence for the classification and conservation of these species. We conducted a comprehensive sequencing and characterization of the complete chloroplast genomes of four species within the genus Callitriche: C. cophocarpa, C. hermaphroditica, C. palustris, and C. stagnalis. The genome sizes ranged from 150,042 to 150,879 bp, with a GC content of 37.5–37.8% and between 131 and 132 genes. Comparative genomic analysis revealed several highly variable intergenic regions (e.g., rps16–psbK, trnS-GCU–trnG-UCC, ccsA–ndhD, ndhF–rpl32, and trnN-UGG) and the ycf1 gene, highlighting their potential as phylogenetic markers. Phylogenetic analyses confirmed the monophyly of Callitriche and supported C. hermaphroditica as an early-diverging lineage within the genus. Notably, the phylogeny also resolved Hemiphragma and Veronicastrum as sister taxa, contributing insights into evolutionary relationships within Plantaginaceae. This study provides comprehensive chloroplast genomic data for Callitriche, offering valuable molecular markers for phylogenetic research, taxonomic clarification, and conservation of this ecologically significant genus. Full article

Background: Section Camellia is the most diverse group in the genus Camellia L., and this group of plants has a long history of cultivation in China as popular ornamental flowers and oil plants. Sect. Camellia plants present diverse morphological variations and complexity among species, resulting in uncertainty in the classification of species, which has resulted in a degree of inconvenience and confusion in the use of plant resources and research. Methods: Here, We sequenced and assembled the chloroplast genomes of 6 sect. Camellia and performed comparative chloroplast genome analysis and phylogenetic studies combined with 15 existing sect. Camellia plants. Results: The chloroplast genome of 21 species in sect. Camellia species were quadripartite with length of 156,587–157,068 bp base pairs (bp), and a highly conserved and moderately differentiated chloroplast genome arrangement. The 21 sect. Camellia chloroplast genomes were similar to those of angiosperms, with high consistency in gene number, gene content and gene structure. After the annotation process, we identified a total of 132 genes, specifically 87 sequences coding for proteins (CDS), 37 transfer RNA (tRNA) genes, and 8 ribosomal RNA (rRNA) genes. The ycf1 gene in 21 species of the sect. Camellia was present only in the small single-copy/inverted repeat of a (SSC/IRa) region. Sequence variation was greater in the large single-copy (LSC) region than in the IR region, and the majority of the protein-coding genes presented high codon preferences. The chloroplast genomes of 21 plant species exhibit relatively conserved SC (single copy region)/IR (inverted repeat region) boundaries. We detected a total of 2975 single sequence repeats (SSRs) as well as 833 dispersed nuclear elements (INEs). Among these SSRs, A/T repeats and AT/AT repeats dominated, while among INEs, forward repeats and palindromic repeats predominated. Codon usage frequencies were largely similar, with 30 high-frequency codons detected. Comparative analysis revealed five hotspot regions (rps16, psaJ, rpl33, rps8, and rpl16) and two gene intervals (atpH-atpI and petD-rpoA) in the cp genome, which can be used as potential molecular markers. In addition, the phylogenetic tree constructed from the chloroplast genome revealed that these 21 species and Camellia oleifera aggregated into a single branch, which was further subdivided into two evolutionarily independent sub-branches. Conclusions: It was confirmed that sect. Camellia and C. oleifera Abel are closely related in Camellia genus. These findings will enhance our knowledge of the sect. Camellia of plants, deepen our understanding of their genetic characteristics and phylogenetic pathways, and provide strong support for the scientific development and rational utilization of the plant resources of the sect. Camellia. Full article

The Hypericaceae family, comprising nine genera and over seven hundred species, includes Hypericum plants traditionally used for medicinal purposes. In this study, we performed high-throughput sequencing on three Hypericum species: Hypericum acmosepalum, Hypericum addingtonii, and Hypericum beanii, and conducted comparative genomic analyses with related species. The chloroplast genome sizes were 152,654 bp, 122,570 bp, and 137,652 bp, respectively, with an average GC content of 37.9%. All genomes showed a quadripartite structure, with significant variations in IR regions (3231–26,846 bp). The total number of genes ranged from 91 to 129. SSRs were predominantly located in the LSC region, with mononucleotide repeats being dominant. Comparative analysis identified several hotspot regions, including accD, rpoC2, rpoB, and rpl22 in the LSC region and matK, rpl32, rpl33, and rps4 in the SSC region. Nucleotide polymorphism analysis revealed eight highly variable regions and eleven gene loci, providing potential molecular markers for species identification. Phylogenetic analysis indicated that Triadenum and Cratoxylum are closely related to Hypericum, with H. acmosepalum and H. beanii being closest relatives and Hypericum hookerianum as their sister species. These findings provide molecular tools for species identification and insights for conservation strategies of medicinal Hypericum species. Full article