Search Results (1,238)

Fructose-1,6-bisphosphatase (FBP) is a crucial regulatory enzyme in sucrose synthesis and photosynthetic carbon assimilation, functioning through two distinct isoforms: cytosolic FBP (cyFBP) and chloroplastic FBP (cpFBP). However, the identification and functional characterization of FBP genes in Saccharum remains limited. In this study, we conducted a systematic identification and comparative genomics analyses of FBPs in three Saccharum species. We further examined their expression patterns across leaf developmental zones, spatiotemporal profiles, and responses to diurnal rhythms and hormonal treatments. Our analysis identified 95 FBP genes, including 44 cyFBPs and 51 cpFBPs. Comparative analyses revealed significant divergence in physicochemical properties, gene structures, and motif compositions between the two isoforms. Expression profiling indicated that both cyFBPs and cpFBPs were predominantly expressed in leaves, particularly in maturing and mature zones. During diurnal cycles, their expression peaked around the night–day transition, with cpFBPs exhibiting earlier peaks than cyFBPs. FBP genes in Saccharum spontaneum displayed greater diurnal sensitivity than those in Saccharum officinarum. Hormonal treatments further revealed significant regulatory divergence in FBP genes, both between isoforms and across species. Notably, cyFBP_2 and cpFBP_2 members consistently exhibited higher expression levels across all datasets, suggesting their pivotal roles in sugarcane physiology. These findings not only identify potential target genes for enhancing sucrose accumulation, but also highlight the breeding value of S. spontaneum and S. officinarum in sugarcane breeding. Full article

Fritillaria unibracteata is a rare and endangered medicinal plant in the Liliaceae family, whose bulbs have been used in traditional Chinese traditional medicine for over 2000 years. The mevalonate (MVA) pathway is involved in the growth, development, response to environmental stress, and active ingredient production of plants; however, the functional characterization of MVA-pathway genes in the Liliaceae family remains poorly documented. In this study, an Acetyl-CoA C-acetyltransferase gene (FuAACT) was first cloned from F. unibracteata. It exhibited structural features of the thiolase family and showed the highest sequence identity with the Dioscorea cayenensis homolog. The K_m, V_max, and K_cat of the recombinant FuAACT were determined to be 3.035 ± 0.215 μM, 0.128 ± 0.0058 μmol/(min·mg), and 1.275 ± 0.0575 min⁻¹, respectively. The optimal catalytic conditions for FuAACT were ascertained to be 30 °C and pH 8.9. It was stable below 50 °C. His361 was confirmed to be a key amino acid residue to enzymatic catalysis by site-directed mutagenesis. Subsequent subcellular localization experiments demonstrated that FuAACT was localized in chloroplasts and cytoplasm. FuAACT-overexpressing transgenic Arabidopsis thaliana plants showed higher drought tolerance than wild-type plants. This phenotypic difference was corroborated by significant differences in seed germination rate, lateral root number, plant height, and leaf number (p < 0.05). Furthermore, the FuAACT transgenic plants resulted in the formation of a more developed fibrous root system. These results indicated that the FuAACT gene revealed substantial biological activity in vitro and in vivo, hopefully providing the basis for its further research and application in liliaceous ornamental and medicinal plants. Full article

Plant mitochondrial genomes are characterized by their complex compositions and structures, large genomes, rapid recombination and evolution rates, and frequent intracellular gene transfer events. Centipedegrass, known as “Chinese turfgrass”, is a warm-season turfgrass that exhibits excellent tolerance to both biotic and abiotic stresses. The chloroplast genome, with 139,107 bp, and the mitochondrial genome, with 564,432 bp, were both assembled into a single circular structure. We identified 44 gene transfer events between the chloroplast and mitochondrial genomes. The mitochondrial gene cox1 could serve as a marker for distinguishing accessions found at different altitudes. The unique features of the centipedegrass mitochondrial genome, coupled with the comparative genomic analysis of both chloroplast and mitochondrial genomes, have the potential to enrich the Poaceae database and provide crucial perspectives on plant evolution, energy metabolism, and responses to environmental conditions. The markers developed could facilitate the analysis of the genetic diversity of centipedegrass. Full article

Plant genetics and chemotaxonomic analysis are considered key parameters in understanding evolution, plant diversity and adaptation. Korean Peninsula has a unique biogeographical landscape that supports various aromatic plant species, each with considerable ecological, ethnobotanical, and pharmacological significance. This review aims to provide a comprehensive overview of the chemotaxonomic traits, biological activities, phylogenetic relationships and potential applications of Korean aromatic plants, highlighting their significance in more accurate identification. Chemotaxonomic investigations employing techniques such as gas chromatography mass spectrometry, high-performance liquid chromatography, and nuclear magnetic resonance spectroscopy have enabled the identification of essential oils and specialized metabolites that serve as valuable taxonomic and diagnostic markers. These chemical traits play essential roles in species delimitation and in clarifying interspecific variation. The biological activities of selected taxa are reviewed, with emphasis on antimicrobial, antioxidant, anti-inflammatory, and cytotoxic effects, supported by bioassay-guided fractionation and compound isolation. In parallel, recent advances in phylogenetic reconstruction employing DNA barcoding, internal transcribed spacer regions, and chloroplast genes such as rbcL and matK are examined for their role in clarifying taxonomic uncertainties and inferring evolutionary lineages. Overall, the search period was from year 2001 to 2025 and total of 268 records were included in the study. By integrating phytochemical profiling, pharmacological evidence, and molecular systematics, this review highlights the multifaceted significance of Korean endemic aromatic plants. The conclusion highlights the importance of multidisciplinary approaches including metabolomics and phylogenomics in advancing our understanding of species diversity, evolutionary adaptation, and potential applications. Future research directions are proposed to support conservation efforts. Full article

Medicago falcata is one of the most important perennial forage legumes in the Medicago genus. In this study, we reported the complete chloroplast genome of two M. falcata ecotypes grown in different regions, and compared them with those of Medicago truncatula and Medicago sativa. We found that the M. falcata chloroplast genome lacks a typical quadripartite structure, containing 78 protein-coding genes, 30 tRNA genes, and four ribosomal RNA genes. They shared high conservation in size, genome structure, gene order, gene number and GC content with those of M. truncatula and M. sativa. High nucleotide diversity occurred in the coding gene regions of rps16, rps3, and ycf4 genes. Meanwhile, mononucleotide repeats are the most abundant repeat type, followed by the di-, tri-, tetra-, and pentanucleotides, and forward repeats were more abundant than reverse and palindrome repeats for all these three Medicago species. Phylogenetic analyses using both coding sequences and complete chloroplast genomes revealed that M. falcata shares the closest phylogenetic relationship with M. hybrida and M. sativa. This study provided valuable information for further studies on the genetic relationship of the Medicago genus. Full article

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

Objectives: Light intensity is a critical environmental factor regulating plant growth, development, and stress adaptation. However, the physiological and molecular mechanisms underlying light responses in Aconitum kusnezoffii, a valuable alpine medicinal plant, remain poorly understood. This study aimed to elucidate the adaptive strategies of A. kusnezoffii under different light intensities through integrated physiological and transcriptomic analyses. Methods: Two-year-old A. kusnezoffii plants were exposed to three controlled light regimes (790, 620, and 450 lx). Leaf anatomical traits were assessed via histological sectioning and microscopic imaging. Antioxidant enzyme activities (CAT, POD, and SOD), membrane lipid peroxidation (MDA content), osmoregulatory substances, and carbon metabolites were quantified using standard biochemical assays. Transcriptomic profiling was conducted using Illumina RNA-seq, with differentially expressed genes (DEGs) identified through DESeq2 and functionally annotated via GO and KEGG enrichment analyses. Results: Moderate light (620 lx) promoted optimal leaf structure by enhancing palisade tissue development and epidermal thickening, while reducing membrane lipid peroxidation. Antioxidant defense capacity was elevated through higher CAT, POD, and SOD activities, alongside increased accumulation of soluble proteins, sugars, and starch. Transcriptomic analysis revealed DEGs enriched in photosynthesis, monoterpenoid biosynthesis, hormone signaling, and glutathione metabolism pathways. Key positive regulators (PHY and HY5) were upregulated, whereas negative regulators (COP1 and PIFs) were suppressed, collectively facilitating chloroplast development and photomorphogenesis. Trend analysis indicated a “down–up” gene expression pattern, with early suppression of stress-responsive genes followed by activation of photosynthetic and metabolic processes. Conclusions: A. kusnezoffii employs a coordinated, multi-level adaptation strategy under moderate light (620 lx), integrating leaf structural optimization, enhanced antioxidant defense, and dynamic transcriptomic reprogramming to maintain energy balance, redox homeostasis, and photomorphogenic flexibility. These findings provide a theoretical foundation for optimizing artificial cultivation and light management of alpine medicinal plants. Full article

GOLDEN2-LIKEs (GLKs) are important transcription factors for the chloroplast development influencing photosynthesis, nutrition, senescence, and stress response in plants. Sunflower (Helianthus annuus) is a highly photosynthetic plant; here, a GLK-homologues gene HaGLK was identified from the sunflower genome by bioinformatics. To analyze the bio-function of HaGLK, transgenic rice plants overexpressing HaGLK (HaGLK-OE) were constructed and characterized via phenotype. Compared to the wild-type control rice variety Zhonghua 11 (ZH11), the HaGLK-OE lines exhibited increased photosynthetic pigment contents, higher net photosynthetic rates, and enlarged chloroplast area; meanwhile, genes involved in both photosynthesis and chlorophyll biosynthesis were also significantly up-regulated. Significantly, the HaGLK-OE plants showed a 12–13% increase in yield per plant. Additionally, the HaGLK-OE plants were demonstrated to have improved salt and drought tolerance compared to the control ZH11. Our results indicated that the HaGLK gene could play multiple roles in photosynthesis and stress response in rice, underscoring its potential value for improving crop productivity and environmental adaptability in breeding. Full article

A yellow leaf mutant named ‘ZT00091’ was discovered during the cultivation of the melon variety ‘ZT091’. An analysis of the leaf ultrastructure revealed that the chloroplasts of ‘ZT00091’ were significantly smaller than those of ‘ZT091’, with irregular shapes, blurred contours, and no starch granules. Metabolomic analysis revealed 792 differentially abundant metabolites between ‘ZT00091’ and ‘ZT091’, with 273 upregulated and 519 downregulated. The Kyoto Encyclopedia of Genes and Genomes (KEGG) results indicated that the differentially abundant metabolites were enriched mainly in the carotenoid pathway. qRT-PCR was used to analyze key genes in the carotenoid pathway of melon. Compared with those in ‘ZT091’, the genes promoting carotenoids and lutein in ‘ZT00091’ were significantly upregulated, which may explain the yellow color of ‘ZT00091’ leaves. Significant differences in the chlorophyll contents (chlorophyll a, chlorophyll b, and total chlorophyll) and carotenoid contents were found between ‘ZT00091’ and ‘ZT091’, indicating that the yellowing of melon leaves is related to changes in the carotenoid and chlorophyll contents. This study provides a theoretical basis for research on the molecular mechanism of melon yellowing. Full article

Nitric oxide is a gaseous signalling molecule produced by plants. Slight changes in endogenous NO levels have significant biochemical and physiological consequences. We investigated the structural and functional properties of NO-responsive antiporter genes in Arabidopsis thaliana. Phylogenetic analysis of 50 antiporter genes classified them into four subgroups based on the presence of NHX and CPA domains and the evolutionary similarity of the protein sequences. Antiporters were found scattered across the five chromosomes with unique physico-chemical properties and subcellular localisation in the plasma membrane, nucleus, chloroplasts, and vacuole. Furthermore, we performed QPCR analysis of eight different antiporter genes after infiltrating the plants with 1 mM CySNO (S-nitroso-L-cysteine), a nitric oxide donor, in WT and the loss-of-function atgsnor1-3 (disruptive S-nitrosoglutathione reductase 1 activity) plants. The AT1G79400 (CHX2), AT2G38170 (RCI4), and AT5G17400 (ER-ANT1) showed a significant increase in their expression in response to CySNO infiltration. However, their expression in atgsnor1-3 plants was found to be lower than in the WT plants, indicating a significant redundancy in the response of these genes to 1 mM levels of CySNO and physiological levels of SNOs in atgsnor1-3. On the other hand, a significant reduction in the expression of AT1G16380 (CHX1), AT2G47600 (MHX1), AT3G13320 (CAX2), and AT5G11800 (KEA6) was observed in WT plants after CySNO infiltration as well as in the leaves of atgsnor1-3 plants. Our study identified three NO-responsive antiporter genes in Arabidopsis, indicating their roles in stress responsiveness and ion homeostasis that could be used for further validation of their roles in NO signalling in plants. Full article

Chloroplasts, as the organelles primarily responsible for photosynthesis, require a substantial supply of iron ions. Conversely, due to Fe toxicity, the homeostasis of these ions is subject to tight regulation. Permease in chloroplast 1 (PIC1) has been identified as the primary iron importer into chloroplasts. However, previous studies suggested the existence of a distinct pathway for Fe transfer to chloroplasts, likely involving mitoferrin-like 1 (MFL1) protein. In this work, Arabidopsis MFL1 (AtMFL1) and its cucumber homolog (CsMFL1) were characterized using, among others, Arabidopsis protoplasts as well as both yeast and Arabidopsis mutants. Localization of both proteins in chloroplasts has been shown to be mediated via an N-terminal transit peptide. At the gene level, MFL1 expression profiles differed between the model plant and the crop plant under varying Fe availability. The expression of other genes involved in chloroplast Fe homeostasis, including iron acquisition, trafficking, and storage, was affected to some extent in both AtMFL1 knockout and overexpressing plants. Moreover, root growth and photosynthetic parameters changed unfavorably in the mutant lines. The obtained results imply that AtMFL1 and CsMFL1, as putative chloroplast iron transporters, play a role in both iron management and the proper functioning of the plant. Full article

Sheath blight (ShB), caused by the necrotrophic fungus Rhizoctonia solani (R. solani), poses severe threats to global rice production. Developing a resistant variety with an ShB-resistance gene is one of most efficient and economical approaches to control the disease. Here, we identified a highly conserved chloroplast-localized stem-loop-binding protein encoding gene (OsCSP41b), which shows great potential in developing an ShB-resistant variety. OsCSP41b-knockout mutants exhibit chlorotic leaves and increased ShB susceptibility, whereas OsCSP41b-overexpressing lines (CSP41b-OE) display significantly enhanced resistance to R. solani, as well as to drought, and salinity stresses. Notably, CSP41b-OE lines present a completely comparable grain yield to the wild type (WT). Transcriptomic analyses reveal that chloroplast transcripts and photosynthesis-associated genes maintain observably elevated stability in CSP41b-OE plants versus WT plants following R. solani infection, which probably accounts for the enhanced ShB resistance of CSP41b-OE. Our findings nominate the OsCSP41b gene as a promising molecular target for developing a rice variety with stronger resistance to both R. solani and multi-abiotic stresses. Full article

The main objective of this study was to reveal the molecular mechanism of the albinism in Schima superba and to identify the related functional genes to provide theoretical support for the optimization of S. superba seedling nursery technology. Combining third-generation SMRT sequencing with second-generation high-throughput sequencing technology, the transcriptomes of normal seedlings and albinism seedlings of S. superba were analyzed and the sequencing data were functionally annotated and deeply resolved. The results showed that 270 differentially expressed transcripts were screened by analyzing second-generation sequencing data. KEGG enrichment analysis of the annotation information revealed that, among the photosynthesis-antenna protein-related pathways, the expression of LHCA3 and LHCB6 was found to be down-regulated in S. superba albinism seedlings, suggesting that the down-regulation of photosynthesis-related proteins may affect the development of chloroplasts in leaves. Down-regulated expression of VDE in the carotenoid biosynthesis leads to impaired chlorophyll cycling. In addition, transcription factors (TFs), such as bHLH, MYB, GLK and NAC, were closely associated with chloroplast development in S. superba seedlings. In summary, the present study systematically explored the transcriptomic features of S. superba albinism seedlings, screened out key genes with significant differential expression and provide a reference for further localization and cloning of the key genes for S. superba albinism, in addition to laying an essential theoretical foundation for an in-depth understanding of the molecular mechanism of the S. superba albinism. The genes identified in this study that are associated with S. superba albinism will be important targets for genetic modification or molecular marker development, which is essential for improving the cultivation efficiency of S. superba. Full article

The genus Lysionotus belongs to the family Gesneriaceae and includes plants with both ornamental and medicinal value. However, genomic-level data on the genus remains scarce. Previous investigations of Lysionotus have predominantly centered on morphological classification, with only limited exploration of molecular phylogenetics. Comparative analysis of chloroplast genomes within the genus would provide valuable insights into the genetic variations and evolutionary patterns of Lysionotus plants. In this study, we present the analysis of 24 newly sequenced chloroplast genomes from Lysionotus-related members, including widely distributed and locally distributed species. The results showed that the 11 plastome sizes of widely distributed species ranged from 152,928 to 153,987 bp, with GC content of 37.43–37.49%; the 13 plastome sizes of locally distributed species ranged from 153,436 to 153,916 bp, with GC content of 37.43–37.48%. A total of 24 chloroplast genomes owned typical quadripartite structures, and the number of tRNA (36 tRNAs) and rRNA (4 rRNAs) were observed for all 24 genomes. However, the number of their protein-coding sequences (CDs) varied at individual levels. No contraction and expansion of IR borders, gene rearrangements, or inversions were detected. mVISTA and Pi showed inverted repeats (IR) region was more conserved than the single copy region, coding region was more conserved than the non-coding region. Additionally, the repeat sequences and codon usage bias of Lysionotus plastomes were also conserved. Our results offer a comprehensive understanding of the genetic differences among these species and shed light on their phylogenetic systematics. Full article

This study evaluated the influence of different male date palm cultivars, distinguished by their chloroplast haplotypes, on pollen quality, pollination efficiency, metaxenia effects, and gene expression during fruit development. Chloroplast DNA analysis of 37 male trees revealed multiple haplotypes, from which cultivars B25, P8, C22, and B46 were selected for further investigation. Pollen viability varied significantly among cultivars, with P8 and B25 exhibiting the highest germination rates and pollen tube elongation, while C22 showed the lowest. These differences correlated with pollination success: P8 and B25 achieved fertilization rates near 99%, whereas C22 remained below 43%. Pollination outcomes also varied in fruit traits. Despite its low pollen performance, C22 induced the production of larger fruits at the Bleh (Kimri) stage, potentially due to compensatory physiological mechanisms. Phytochemical profiling revealed significant cultivar effects: fruits from B25-pollinated trees had with lower moisture and polyphenol content but the higher sugar levels and soluble solids, suggesting accelerated maturation. Ripening patterns confirmed this finding, with B25 promoting the earliest ripening and B46 causing the most delayed. Gene expression analysis supported these phenotypic differences. Fruits pollinated by P8, B25, and B46 exhibited elevated levels of cell-division-related transcripts, particularly the PdCD_1 gene (PDK_XM_008786146.4, a gene encoding a cell division control protein), which was most abundant in P8. In contrast, fruits from C22-pollinated trees had the lowest expression of growth-related genes, suggesting a shift toward cell expansion rather than division. Overall, the results show the critical role of male genotype in influencing fertilization outcomes and fruit development, offering valuable insights for targeted breeding strategies at enhancing date palm productivity and fruit quality. Full article