Plant Molecular Biology
○ Springer Science and Business Media LLC
Preprints posted in the last 90 days, ranked by how well they match Plant Molecular Biology's content profile, based on 18 papers previously published here. The average preprint has a 0.01% match score for this journal, so anything above that is already an above-average fit.
Nagalla, A. D. D.; Morita, R.; Ichida, H.; Hayashi, Y.; Shirakawa, Y.; Ichinose, K.; Sato, T.; Toriyama, K.; Abe, T.
Show abstract
Photoperiod sensitivity (PS) is a key biological response in plants as they adapt to specific environments. Rice (Oryza sativa L.) exhibits a clear PS, as it implements critical phase transition decisions based on PS signals. In this study, we identified a novel PS gene, JMJ706, that is expected to deliver photoperiod-related signals to the flowering-time regulatory network in a day-length-dependent manner. The JMJ706 mutants exhibit early flowering under LD and later flowering under SD compared to WT plants. The gene encodes an H3K9me2 demethylase, and under long-day (LD) conditions, its demethylase activity facilitates the expression of Grain number, Plant height, and Heading-date7 (Ghd7). Since Ghd7 is a floral repressor in LD, it promotes the vegetative phase by delaying flowering. Under short-day conditions (SD), H3K9me2 demethylase activity facilitates Early heading-date 1 (Ehd1) expression, and it acts as a floral accelerator by inducing Heading date 3 (Hd3a) and RICE FLOWERING LOCUS T 1 (RFT1). Furthermore, we propose that the daylength-dependent promotion of target genes (Ghd7 and Ehd1) occurs through demethylation of specific promoter regions at a crucial time window. In addition, JMJ706 may play an important role in regulating plant architecture, including plant height. The natural variation in JMJ706 alleles shows high frequencies across major rice subpopulations, suggesting that JMJ706 could play an important role in the geographical distribution and adaptation of rice cultivars. Our results may add a new layer to the rice flowering-time regulatory pathway, supporting regional adaptation and potential for future breeding.
Zhuang, Q.; Cao, S.; Zhang, L.; Wang, H.; Li, W.; Wang, Z.; Zhu, G.; Lu, W.; He, C.; Gao, W.; Chen, C.; Ma, C.; Zhang, H.; Chang, C.
Show abstract
In wheat, weak seed dormancy (SD) is related to an increased tendency for pre-harvest sprouting (PHS), which reduces yield and quality. However, the molecular mechanism underlying SD remains elusive. Here, we identified a wheat R2R3-MYB transcription factor (TaMYB83-7B) related to SD. Expression analysis showed that TaMYB83-7B was highly expressed in wheat seeds, and was more highly expressed in strong-dormancy varieties than in weak-dormancy varieties. Sequence and association analysis indicated that T/C mutations at -907 bp and -1133 bp in the TaMYB83-7B promoter were significantly associated with wheat SD, with C at both sites related to strong dormancy. Dual-luciferase reporter assays demonstrated that the transcriptional activity of the TaMYB83-7B promoter was significantly higher in strong-dormancy varieties than in weak-dormancy varieties. Further analyses indicated that TaMYB83-7B functions as a transcriptional inhibitor. Germination experiments revealed that overexpression of TaMYB83-7B significantly enhanced SD, while its loss-of-function reduced SD. Finally, TaMYB83-7B was found to regulate SD by influencing the balance between abscisic acid (ABA) and gibberellin (GA) in wheat seeds. Overall, the results of this study enhance our understanding of the complex regulatory mechanism underlying SD, and provide gene targets and molecular markers for the genetic improvement of PHS resistance in wheat.
Wan, J.; Yang, M.; Song, J. H.; Xu, C.; Cho, S.-H.; Zhou, M.; Pasa-Tolic, L.; Yang, B.; Xu, D.; Stacey, G.
Show abstract
Previously, the chitin receptor-interacting protein kinase LIK1 (LysM receptor kinase 1/CERK1-interacting kinase) was shown to play an important role in regulating chitin signaling and plant defense. A limited proteolysis proteomics study revealed several LIK1-derived peptides that showed differential abundance between ATP-treated and mock-treated Arabidopsis samples, suggesting a possible involvement of LIK1 in extracellular ATP (eATP) signaling. To explore this possibility, LIK1 mutants were obtained and examined for their response to ATP. The results showed that mutations in LIK1 significantly reduced the expression of eATP-responsive genes. In addition, LIK1 was found to interact with the eATP receptor P2K1 and to be phosphorylated by it. The LIK1 protein was localized to the plasma membrane and its gene expression appeared to be ubiquitous. Collectively, these findings indicate that LIK1 not only contributes to chitin signaling but also participates in eATP signaling, highlighting its potential role as a shared component in multiple signaling pathways to regulate plant responses to diverse internal and external cues.
Magyar, Z.; Hamid, R. S. B.; Vadai-Nagy, F.; Gombos, M.; Domonkos, I.; Perez-Perez, J. M.; Feher, A.
Show abstract
The RETINOBLASTOMA-RELATED (RBR) protein in plants functions as a cell-cycle inhibitor, regulating cell numbers in developing organs and establishing cellular quiescence during growth. Although the role of RBR counterparts in animals also involves regulating cell size, this potential function remains unexplored in plants. We investigated transgenic Arabidopsis plants with altered RBR levels and observed corresponding changes in cell size from embryogenesis through organ development. In addition, stomatal meristemoid cells with reduced RBR levels divided beyond the size threshold, whereas elevated RBR levels increased their size. RBR stimulated terminal differentiation in the stomatal lineage by inducing MUTE and CYCLIN D5;1 expression, whereas reduced RBR levels maintained asymmetric divisions through high SPEECHLESS and CYCLIN D3;1 expression. Interestingly, the cell proliferation-dependent phosphorylation of RBR at the conserved 911Ser site positively correlated with RBR protein levels in the transgenic lines and aligned with the effect of RBR on cell size. This study discusses the potential link between RBRs control of cell proliferation and cell size, providing new insights into the coordinated regulation of plant development.
Panigrahi, J.; Panigrahy, D.; Rath, B.; Gupta, K.
Show abstract
Heavy metal ATPases (HMAs) are important group of transmembrane proteins involved in homeostasis of metal ions in plant systems. In this study, a comprehensive analysis of genome assembly (VC1973A v7.1) resulted in the identification of nine HMA genes (VrHMA) and their corresponding proteins in Mungbean, an agronomically important legume crop known for its nutritional values. VrHMA proteins were also characterized based on their biomolecular features, conserved domains and motifs arrangement, transmembrane helices, pore-line helices, subcellular location and occurrence of signal peptides. Based on sequence homology, nine VrHMAs were clustered into two major substrate-specific groups: VrHMA1, VrHMA5 and VrHMA7 were categorized under the Zn/Co/Cd/Pb ATPase group, whereas the remaining six VrHMAs belong to the Cu/Ag subgroup. Gene structure analysis and promoter scanning revealed the structural divergence and presence of various stress-responsive cis-acting elements, respectively. The expression analysis of VrHMA genes in root and leaf tissues, in response to heavy metal (Zn, Cd and Cu) stress, indicates their role in the uptake, transport and sequestration of metal ions. Interestingly, VrHMA5 showed incremental upregulation in roots in response to all three heavy metal stresses, whereas its expression was only upregulated in the leaf tissues under Zn stress, which indicates its role in vascular transport in V. radiata. In addition, this study provides valuable insights into the functional roles of VrHMA genes and will lay a foundation for future genetic improvement in mung bean aimed at enhanced heavy metal stress tolerance and micronutrient homeostasis.
Poudel, A.; Wu, Y.
Show abstract
Common bermudagrass (Cynodon dactylon) is a highly resilient and cosmopolitan grass widely used for turf, forage, and soil stabilization. Although its genome has been sequenced, little study has focused on characterizing genes underlying its resilience, including the NAC transcription factor family, which is well known for its physiological and stress-related functions. This study aimed to systematically characterize NAC TF genes in the bermudagrass genome and assess their potential roles in abiotic stress tolerance. A total of 237 CdNAC genes were identified and phylogenetically classified into 14 groups, including 40 members in the NAM/NAC1 class, which is associated with plant growth and development, and 23 members in the SNAC class, which is associated with stress responses. Tissue-specific RNA-seq analysis indicated that about one-fourth of CdNAC genes were expressed across all tissues, whereas 13 genes showed relatively higher expression in roots and 9 in inflorescence, suggesting both essential and specialized functions. Stress-responsive expression profiling revealed that 35 CdNAC genes were upregulated in response to drought, 43 to heat, 10 to salt, and 42 to submergence stress. Notably, CdNAC122, 149, and 155, the members of SNAC class, were consistently upregulated across all stress conditions, while others exhibited stress-specific expression, such as CdNAC37, 130, 145, and 199 in drought, CdNAC7, 12, 18, and 29 in heat, CdNAC46 and 151 in salt, and CdNAC9 and 31 in submergence. In contrast, 53 genes were downregulated during different stresses, with most belonging to NAM/NAC1, TERN, or OsNAC7 classes, possibly reflecting suppression of photosynthesis and development-related processes under stress. These results provide the first comprehensive characterization of CdNAC genes, reveal their distinct regulatory roles in abiotic stress responses, and establish a foundation for future functional validation and applications in breeding of stress-resilient bermudagrass.
Wijesingha Ahchige, M.; Mengin, V.; Raines, C. A.
Show abstract
Improving regeneration of ribulose-1,5-bisphosphate (RUBP) is a promising approach to improve photosynthesis and plant growth. In addition to transgenic overexpression of target genes, it could be possible to directly overexpress endogenous target genes, through transcriptional enhancements. As shown by the recent discovery of a short sequence motif, that resembles the known octopine synthase (ocs) enhancer, transcriptional enhancement is achievable by relatively short endogenous sequences. In this study, we query the genome of several model and crop plant genomes for the presence of short enhancer motifs. We find hits across all genomes including some in promoter regions of genes. By using derivatives of these motifs in a transient fluorescence assay, we show that several of these are capable of inducing target gene expression in different promoter contexts. A motif scan of the created constructs, for the presence of known transcription factor binding sites, shows that the insertion of these motifs has created binding sites for different TGA-, NAC- and bZIP-transcription factors. Taken together our study shows the feasibility of finding enhancer sequences in the genomes of different plants. With advancement in gene-editing technologies, like prime editing, using such endogenous enhancer sequences, could allow for precise cisgenic promoter engineering of target genes.
Njah, R. G.; Randall, S. K.; Davik, J.; Johansen, W.; Alsheikh, M. K.; Wilson, R. C.; Grini, P. E.
Show abstract
Low temperature stress causes significant damage to the strawberry plant. During cold stress, plants undergo morphological and physiological changes often regulated at the genetic and/or epigenetic levels. Some strawberry cultivars are more cold-hardy than others. Using the diploid woodland strawberry as a model, we analyzed the effects of cold acclimation on methylome and transcriptome dynamics in the crowns and leaves of three ecotypes with contrasting cold tolerance. Alta, which was the most cold-tolerant ecotype, exhibited the highest genetic and epigenetic plasticity in response to cold. CHH-context methylation dominated the differentially methylated regions (DMRs) with more hypomethylation in crowns and hypermethylation in leaves. CG methylation was enriched in gene bodies, while non-CG methylation was prevalent in upstream and downstream regions. Our study revealed that less than a quarter of differentially methylated genes (DMGs) showed changes in transcript accumulation levels. This finding indicates that universal cold response in Fragaria vesca, as reflected by gene expression, cannot be mechanistically attributed to DNA methylation. The majority of differentially expressed differentially methylated genes (DEDMGs) were ecotype- and tissue-specific. Enrichment analysis revealed that these genes were involved in pathways related to stress tolerance, such as carbohydrate metabolism, lipid metabolism, ATP hydrolysis, and cellular detoxification. Each ecotype responded to cold through mobilization of its own set of differentially expressed genes (DEGs), DMGs, and DEDMGs, and variation in expression and methylation patterns exhibited by Alta, FDP817, and NCGR1363 suggest that cold signaling processes and survival depend on the tissue, ecotype, and geographical origin of the plants exposed to cold stress. Therefore, this study highlights the potential of both genetic markers and epialleles as molecular markers for the development of cold-tolerant octoploid strawberry cultivars that are better suited for propagation in Nordic climates.
Ueda, T.; Adachi, S.; Sugimoto, K.; Maeda, M. H.; Yamanouchi, U.; Mizobuchi, R.; Taniguchi, Y.; Hirasawa, T.; Yamamoto, T.; Tanaka, J.
Show abstract
Improving rice (Oryza sativa L.) yield requires a balanced enhancement of both sink size and source capacity. While many QTLs for sink size have been identified, only a few are known for source capacity, which is essential for achieving high yield. Here we identified qHP10 as a major QTL for increased photosynthetic rate by using chromosome segment substitution lines derived from a cross between the high-yielding indica cultivar Takanari and the average-yielding japonica cultivar Koshihikari. High-resolution mapping combined with CRISPR/Cas9-induced mutagenesis revealed that the causative gene underlying qHP10 is Mitogen-Activated Protein Kinase 4 (OsMPK4). A near-isogenic line carrying the OsMPK4Takanari allele (NIL-OsMPK4) had a 15-25% higher photosynthetic rate than Koshihikari. NIL-OsMPK4 also had higher stomatal conductance than Koshihikari but similar stomatal pore size and density, indicating that increased stomatal aperture increases photosynthetic rate. This enhancement is likely attributable to the down-regulation of OsMPK4 expression, which increases stomatal conductance and thus promotes CO2 uptake. Our findings demonstrate that OsMPK4 is a promising genetic target for increasing source capacity and, potentially, rice yield through molecular breeding. (175 words)
Parra, A. R.; Balao, F.
Show abstract
Phenotypic plasticity is a key mechanism by which plants adjust their traits to environmental changes. These phenotypic adjustments are driven by plastic changes in gene expression regulated by gene regulatory networks. Drought, a major selective force in Mediterranean ecosystems, provides a powerful context to examine how genomic plasticity translates into phenotypic responses. Here, we used Dianthus inoxianus, a drought-tolerant Mediterranean carnation, in order to characterize the phenotypic and transcriptomic plasticity in response to drought stress combining ecophysiological measurements with RNA-seq, gene co-expression and gene regulatory network analyses. Most of the phenotypic traits exhibited low plasticity in response to drought, except water and osmotic potential. At transcriptome level, we identified 57 plastic genes, suggesting that drought tolerance in D. inoxianus relies predominantly on constitutive gene expression. These plastic genes were enriched in processes typically related to drought response, such as cell wall components and abscisic acid (ABA) signaling. Some plastic genes belonged to drought-responsive modules, while others were hubs in different modules acting as inter-modular connectors. Furthermore, the regulatory network revealed that these plastic genes were strongly regulated by multiple stress-responsive transcription factors, and that drought-associated modules were regulated through both ABA-dependent and ABA-independent pathways. In addition, we identified contrasting patterns of canalization and decanalization, with immune and post-transcriptional regulation remaining canalized under drought, whereas photosynthesis and amino acid metabolism became decanalized, potentially releasing cryptic genetic variation. Overall, our results emphasise that drought tolerance in D. inoxianus emerges from a strategy combining preadaptation with targeted plasticity in key molecular pathways.
Zhou, W.; Zheng, J.; Zhou, S.; Guo, Y.; Kong, D.; Yang, P.; Zhang, B.
Show abstract
Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are essential regulators of plant growth, development, and stress adaptation. In this study, we performed a comprehensive genome-wide identification of SNARE genes in cucumber (Cucumis sativus L.), uncovering 51 putative members designated as CsSNAREs. Phylogenetic analysis confirmed that these genes cluster into five major clades: Qa-CsSNARE (14), Qb-CsSNARE (9), Qc-CsSNARE (10), Qb+c-CsSNARE (3), and R-CsSNARE (15). Bioinformatic analysis of their promoter regions, coupled with expression profiling under diverse abiotic stress conditions, highlighted a heightened responsiveness within the Qa-CsSNARE subfamily. To validate this, we selected representative Qa-CsSNARE genes for quantitative real-time PCR analysis under drought and salt stress. Among these, CsSYP121 was notably induced by salt treatment. We subsequently generated transgenic cucumber lines overexpressing CsSYP121 and challenged them with salinity. Phenotypic assessment, combined with measurements of reactive oxygen species (ROS) accumulation and K+/Na+ ratios, demonstrated that CsSYP121 overexpression (OE) confers enhanced salt tolerance and boosts antioxidant capacity. We propose a model wherein CsSYP121 mitigates ROS-induced cellular damage under salt stress, potentially through promoting K+/Na+ homeostasis, thereby improving plant performance under saline conditions. Our findings identify CsSYP121 as a promising candidate gene for breeding salt-tolerant crops.
Pfeifer, M.; Peil, A.; Flachowsky, H.; Emeriewen, O. F.; Woehner, T. W.
Show abstract
Apple blotch, caused by Diplocarpon coronariae, is an increasingly important fungal disease that leads to premature leaf fall and significant yield losses in apple orchards. Breeding resistant cultivars offers a sustainable strategy to reduce disease impact, as all commercial apple cultivars are susceptible to this pathogen. This study aimed to investigate the disease resistance of Malus baccata Jackii-derived offspring to D. coronariae through artificial inoculation and to identify loci associated with resistance. Simple interval mapping was performed using phenotypic and genotypic data from 122 individuals of an F1 population (Idared x M. baccata Jackii), together with analyses of M. baccata Jackii-derived open-pollinated populations. Our results indicate that resistance to apple blotch is a complex, polygenic trait, with four important QTLs identified on linkage groups 1, 2, 12 and 13. Disease severity was strongly affected by inoculum, phenotyping method and environmental factors. These findings have direct implications for apple breeding programmes aimed at developing apple blotch-resistant cultivars.
Andotra, S.; Shafeeq, K.; Pal, K.; Majeed, A.; Misra, P.
Show abstract
Members of the HD-ZIP transcription factor family play an important role in plant processes, including growth, development, metabolism, and stress response regulation. Among these, the sub-family IV members regulate epidermal cell differentiation, trichome development, and secondary metabolism. Monarda citriodora, an aromatic plant, produces economically important essential oils enriched in thymol. Thymol and other related monoterpenes are primarily biosynthesized and stored in glandular trichomes. Despite its significant economic value, the comprehensive identification of the transcription factor families has not been studied in this plant species. Given the importance of HD-ZIP-IV members in regulating trichome development and secondary metabolism, we identified these members in M. citriodora in the present study. To this end, firstly, we carried out transcriptome sequencing of M. citriodora flowers, and the resulting reads, along with previously sequenced reads, were used to reconstruct a transcriptome assembly. The assembled transcripts represented all major plant parts. Using this improved assembly, HD-ZIP-IV members were identified. Their expression profiles and phylogenetic positions, in conjunction with those of known regulators, identified candidate genes involved in the secondary metabolism and/or trichome development in M. citriodora. Furthermore, through gene co-expression analysis, several McHD-ZIP-IV members were found to be co-expressed with McDXS and McTPS genes. These McHD-ZIP-IV members may serve as key candidate genes for functional analysis to determine the regulation of trichome development in M. citriodora. Taken together, the present study provides a resource for improving M. citriodora using molecular tools.
Gregoire, M.; Pateyron, S.; Brunaud, V.; Tamby, J. P.; Benghelima, L.; Martin, M.-L.; Girin, T.
Show abstract
AO_SCPLOWBSTRACTC_SCPLOWNitrogen fertilizers are essential for crop productivity but cause environmental harm, necessitating the development of cultivars that thrive under limited nitrogen. This study investigates the transcriptomic response to nitrate in Arabidopsis thaliana (a model dicot), Brachypodium distachyon (a model Pooideae), and Hordeum vulgare (barley, a domesticated Pooideae) to identify conserved and species-specific molecular mechanisms. Using RNA-seq after 1.5 and 3 hours of nitrate treatment, we found that core nitrate-responsive biological processes - such as nitrate transport, assimilation, carbon metabolism, and hormone signaling - are largely conserved across species. However, comparative analysis at gene level based on orthology revealed specificities between the species. For instance, rRNA processing was uniquely stimulated in Arabidopsis, while cysteine biosynthesis from serine and gibberellin biosynthesis were specifically regulated in Brachypodium and barley. Orthologs of key nitrate-responsive genes (e.g., NRT, NLP, TCP20) exhibited variable regulation, reflecting potential adaptations linked to domestication or nutrient acquisition strategies. These findings highlight the importance of integrating model and crop species to uncover targets for improving nitrogen use efficiency in cereals. The study provides a pipeline integrating gene ontology and orthology analyses to compare transcriptomic responses between species.
Cacao, M. A.; Munoz, J. A. M.; Coronado, J. E.; Yanos, L. A.; Cardona, D. E. M.; Gueco, L. S.; Villanueva, J. C.; Palao, C. D.; Alonday, R. C. S.
Show abstract
Garcinia binucao (Blanco) Choisy is an indigenous species endemic to the Philippines. Its fruit is traditionally used as a souring agent in local cuisine and has been reported to possess nutritional and medicinal properties. Despite its ethnobotanical significance and promising bioactive properties, the species remains underutilized. To date, no genomic resources have been published for G. binucao, limiting its application in food systems, genetic studies, and conservation programs. This study reports the first complete chloroplast genome of G. binucao from an accession conserved at the Institute of Plant Breeding, University of the Philippines Los Banos. The assembled plastome is circular with a length of 156,570 base pairs (bp). It displays the typical quadripartite structure of most angiosperms, consisting of a large single-copy (LSC) region (85,357 bp), a small single-copy (SSC) region (17,129 bp), and a pair of inverted repeats (IR), each 27,042 bp in size. A total of 128 genes were annotated, including 83 protein-coding genes, 37 transfer RNAs (tRNAs), and eight ribosomal RNAs (rRNAs), consistent with the majority of Garcinia species. Of the protein-coding genes, 45 are involved in photosynthesis, 28 genes for self-replication, five genes with conserved open reading frames, and five genes are associated with other functions. The GC content was 36.2%. Leucine (10.6%) was the most abundant amino acid, with a codon usage bias toward UUA. Additionally, 98 simple sequence repeats (SSRs) were detected, 88.78% consisting of A/T motifs. Phylogenomic analysis based on assembled plastome and publicly available cpDNA sequences of 17 other species in the order Malpighiales revealed that G. indica is the closest relative of G. binucao. These findings provide a framework for future research on the species, including its conservation and potential use as a genetic resource.
Barth, P.; Drumm, J.; Schmidt, A. E.; Hartig, F.; Koch, A.
Show abstract
RNA interference (RNAi) shows great potential to protect crops against fungal diseases, yet reported protection efficiencies vary greatly, and our understanding of the factors responsible for this variance remains limited. In this meta-analysis, we evaluated 89 studies that compare the efficiency of host-induced gene silencing (HIGS) and spray-induced gene silencing (SIGS) in controlling fungal diseases, focusing on biotrophic, hemibiotrophic, and necrotrophic fungi, the use of formulations, and the dsRNA design as explanatory factors for differences between reported efficiency values. Our results indicate that SIGS is slightly more effective, particularly in biotrophs. Surprisingly, SIGS studies using formulations did not outperform those applying naked dsRNA. We also assessed parameters of RNA design. Differences in dsRNA length and the number of constructs, and number of targets showed no consistent significant effect on resistance in either HIGS or SIGS. Interestingly, however, HIGS studies reported significantly higher efficiency when targeting genes closer to the 3 end and SIGS when targeting genes closer to the 5 end. We discuss potential reasons for the reported patterns, such as variability in dsRNA uptake mechanisms, intercellular trafficking and Dicer processing, and conclude that more research is needed to understand the biological mechanisms determining RNAi efficiency for fungal control.
gupta, S.; Misra, P.; Singh, R.; Dhar, M. K.
Show abstract
Cytochrome P450 monooxygenases (CYP450s) are key oxidative enzymes that diversify plant specialized metabolites and play a central role in the biosynthesis of bioactive withanolides in Withania somnifera (L.) Dunal. Despite their importance, genome-wide information on CYP450s in W. somnifera has remained elusive. Herein, the first high-quality genome assembly (2.2 Gb, scaffold N50: 47.4 kb) of an Indian W. somnifera cultivar was generated using a hybrid Oxford Nanopore-Illumina sequencing strategy. Comparative analysis with the NCBI reference genome revealed moderate SNP and indel variations, reflecting intraspecific genetic diversity. A comprehensive CYP450 catalog was established and analyzed phylogenomically across nine plant genomes, encompassing both withanolide-producing and non-producing Solanaceae and non-Solanaceae species. Unique CYP families (CYP450A, CYP1194, and CYP705A) were detected exclusively in W. somnifera, suggesting lineage-specific metabolic innovations, while Solanaceae-restricted (CYP82E/M) and absent (CYP81B, CYP6) lineages highlight taxonomic divergence. Across all analyzed genomes, 36 conserved CYP450 subfamilies, including triterpenoid-associated members, were identified, suggesting a shared oxidative framework adaptable to specialized metabolism. Moreover, potential candidate genes in the triterpenoid pathway, including CYP72A692_1, CYP72A560_4, CYP716A48, CYP724B2, and CYP51G1, were identified through phylogenetic integration with functionally validated triterpenoid-modifying enzymes from other plant species. Gene family evolution analysis further revealed contraction of monoterpenoid-related subfamilies (CYP76A), implying a metabolic shift toward triterpenoid specialization. The comprehensive genome assembly and CYPome of W. somnifera offer a valuable resource for functional characterization, evolutionary analysis, and the identification of genes underlying its specialized metabolism. Furthermore, the study advances our understanding of CYP450 diversity and evolution, revealing lineage-specific innovations, conserved subfamilies, and key candidate genes involved in triterpenoid biosynthesis. Together, these findings lay a foundation for future functional studies and pathway engineering aimed at optimizing the metabolic potential of this important medicinal plant.
Hu, Y.; Huang, Y.; Yong, Y.; Shang, E.; Zhang, B.; Sui, Z.
Show abstract
As an important cultivated red alga, Gracilariopsis lemaneiformis has great economic and ecological value. However, its existing genome assembly is highly fragmented and inadequately annotated. In this study, we constructed the first high-quality chromosome-level genome of Gp. lemaneiformis using PacBio long reads, Illumina short reads and Hi-C sequencing data. The assembled genome was approximately 86.66 Mb and the assembled sequences were anchored to 28 pseudo-chromosomes with lengths ranging from 1.70 to 7.81 Mb. 99.91% of the PacBio reads could be mapped to our assembly. In total, 8,664 genes were annotated, and the repeat elements identified in Gp. lemaneiformis constituted 65.04% of the whole genome, including 2.24% tandem repeat sequences and 62.81% interspersed repeats. We also established a high-evidence phylogenetic tree from 19 representative algae species, with the main aim to calculate their divergence times. This high-quality genome of Gp. lemaneiformis provides a crucial foundation for understanding genetic characteristics, investigating the genomic evolution, and facilitating molecular breeding.
Das, A. K.; Mostofa, M. G.; Lee, D.-S.; Yun, B.-W.
Show abstract
RAP2.6, an AP2/ERF transcription factor (TF), regulates plant stress responses; however, its role in floral transition remains unexplored. Here, we evaluated RAP2.6s role in flowering and the associated transcriptional changes in Arabidopsis thaliana under long-day conditions. RAP2.6-overexpressing line showed early flowering with fewer rosette leaves, whereas rap2.6-1 mutant flowered later, had more rosette leaves, and higher expression of the floral repressor FLOWERING LOCUS C (FLC). Early flowering in the overexpressing line was accompanied by transcriptional activation of the floral integrators GIGANTEA (GI), FLOWERING LOCUS T (FT), and COSTANS (CO), potentially through RAP2.6 interaction with GCC/DRE cis-regulatory elements. RAP2.6-mediated floral transition depended on nitric oxide (NO), with flowering time largely varying based on NO bioactivity. RAP2.6 was found to be a downstream regulator of Arabidopsis S-NITROSOGLUTATHIONE REDUCTASE 1 (GSNOR1) in controlling S-nitrosothiol (SNO) levels, flowering time, and silique formation. The NITRIC OXIDE-ASSOCIATED 1 (NOA1)-dependent reduction in NO levels abolished early flowering in 35S::RAP2.6 plants without affecting silique formation. Furthermore, enhanced cytokinin sensitivity and upregulation of cytokinin biosynthetic genes suggest cytokinin involvement in RAP2.6-mediated flowering. Together, these findings highlight the crucial role of RAP2.6 in regulating flowering time by integrating redox and hormonal signaling to coordinate reproductive development in A. thaliana.
Murodov, A. A.; Ayubov, M. S.; Mirzakhmedov, M. K.; Obidov, N. S.; Mamajonov, B. O.; Yusupov, A. N.; Bashirxonov, Z. H.; Kamalova, L. K.; Kushakov, S. O.; Bozorov, I. E.; Buriev, Z. T.; Abdurakhmonov, I. Y.
Show abstract
Obtaining tomato plants with firm and intact fruit is one of the main goals in tomato breeding programs. Achieving these goals through conventional breeding is time-consuming and can lead to the loss of unwanted traits. In other hand, consumers are concerned about the presence of transgenic elements in plants acquired through RNA interference. The use of CRISPR/Cas9 technology has made it possible to overcome the above-mentioned shortcomings. In this study, the {beta}-D-N-acetylhexosaminidase ({beta}-hex) gene, which is involved in tomato fruit ripening, was knocked out using CRISPR/Cas9. In the resulting mutant plant genome, an indel mutation was found in exons 1 and 2 of the {beta}-hex gene. Plants with a mutation in their genome were observed to have increased fruit firmness and shelf life compared to control plants without affecting fruit quality.