Search Results (149)

Blue fescue (Festuca glauca) is a widely used ornamental grass worldwide. Drought is an important limiting factor for the growth and development of blue fescue; therefore, cultivating new strains of blue fescue with a strong drought tolerance is of great significance for its production practice. To investigate the drought tolerance mechanism of ds-1, this study subjected both ds-1 and “Festina” to a natural drought treatment and measured their physiological and biochemical indicators. A transcriptomic analysis was also conducted to explore the underlying molecular mechanisms. The results showed that, after the drought treatment, the relative water content (RWC), water use efficiency (WUE), and photosynthetic rate (Pn) of ds-1 leaves were significantly higher than those of “Festina”; in addition, the contents of H₂O₂ and O₂⁻, the relative electrical conductivity (REC), the malondialdehyde (MDA) content, the gas conductance (Gs), and the transpiration rate (Tr) were significantly lower than those of “Festina”. The peroxidase (POD) activity of ds-1 was significantly higher than that of “Festina”, while the superoxide dismutase (SOD) activity of ds-1 was significantly lower than that of “Festina”. The transcriptome data analysis showed that there were a total of 9475 differentially expressed genes (DEGs) between ds-1 and “Festina”. A Venn plot analysis showed 692 DEGs between ds-1—8d vs. “Festina”—8d and ds-1—16d vs. “Festina”—16d. A KEGG enrichment analysis showed that these 692 genes were mainly enriched in 86 pathways, including those related to the photosynthesis antenna protein, plant hormone signal transduction, MAPK signaling, starch and sucrose metabolism, and arginine and proline metabolism. Further screening identified genes that may be associated with drought stress, including PYL, PP2C, SnRK2, ABF, BRI1, JAZ, MYC2, Lhc, and MPK6. The qRT-PCR results indicated that the expression trends of the DEGs were consistent with the transcriptome sequencing results. Our research results can provide a basis for exploring candidate genes for drought tolerance in blue fescue. In addition, our research results provide valuable genetic resources for the development of drought-resistant ornamental grass varieties, which can help reduce water consumption in cities and decrease labor and capital investment. Full article

Mitogen-activated protein kinases 3 and 6 (MPK3/MPK6) are central to pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) in Arabidopsis, yet the involvement of long noncoding RNAs (lncRNAs, >200 nt) in these pathways is poorly understood. Here, transcriptomic analyses were performed to compare lncRNA and protein-coding gene (PCG) expression profiles in wild-type (WT) and MPK3/MPK6-deficient (MPK6SR) Arabidopsis plants. These plants were inoculated with either Pseudomonas syringae pv. tomato (Pst) DC3000, which elicits both PTI and ETI, or its type III secretion-deficient mutant, Pst DC3000 hrcC⁻, which induces only PTI. RNA sequencing (RNA-seq) analysis of 18 samples identified 1388 known and 70 novel lncRNAs, among which differentially expressed lncRNAs (DElncRNAs) involved in disease resistance were further identified. Using integrative analyses, including weighted gene co-expression network analysis (WGCNA), prediction of lncRNA cis-regulatory targets for PCGs, and validation via reverse transcription-quantitative PCR (RT-qPCR), three core lncRNA-mediated regulatory modules were identified: (i) MPK3/MPK6-dependent PTI and ETI, where lncRNAs amplify signals; (ii) MPK3/MPK6-dependent PTI, where lncRNAs fine-tune basal immunity; and (iii) MPK3/MPK6-independent PTI and ETI, where lncRNAs serve as a backup regulatory network. These modules form a multi-layered immune regulatory network via cis- and trans-regulation and further enable the identification of lncRNA-PCG pairs involved in both regulatory modes. This work enhances the understanding of the molecular mechanisms underlying plant innate immunity. Full article

Hydrogen peroxide (H₂O₂) application in several plant species has been widely studied as a plant biostimulant; however, the use of acoustic emissions related to hydric stress (MHAF) in biostimulating plants has not been widely studied, including the response of plants to the interaction of different stress factors. The aim of the present work was to evaluate the stress response in some morphological, biochemical, and molecular variables of the single or combined application of H₂O₂ and MHAF in C. annuum L. plants. Acoustic emission frequencies were obtained in a previous study where the frequencies came from C. annuum plants submitted to medium hydric stress (MHAF). Our results showed that the combination of the two stressors evaluated has a possible synergistic effect on variables such as SOD activity and relative gene expressions of ros1, met1, and MAPkinases (mkk5, mpk4-1, mpk6-2), as well as an antagonistic effect for flavonoid content, DPPH, and ABTS free radical inhibition, and def1 gene expression. MHAF showed increased plant height, PAL activity, and mpk6-1 and erf1 gene upregulation, while H₂O₂ increased POD activity and upregulated pr1a gene. These findings suggest possible stress response pathways that are activated and enhanced by the presence of these stress factors, both individually and in conjunction with one another, making it possible to use them as novel strategies for agricultural stress management. Full article

Background: Mushroom penetrating keratoplasty (MPK) is an alternative to traditional penetrating keratoplasty (PK) that offers improved graft survival and reduced immunological rejection. However, MPK grafts may still experience endothelial failure over time. This study evaluates the outcomes of non-Descemet Stripping Automated Endothelial Keratoplasty (nDSAEK) as a surgical approach for endothelial decompensation following MPK. Methods: A monocentric, retrospective study was conducted at the Ophthalmology Department of Sant’Orsola-Malpighi Hospital, including patients who underwent nDSAEK for endothelial failure after MPK between 2022 and 2024. Pre- and postoperative best-corrected visual acuity (BCVA), central corneal thickness (CCT), and endothelial cell density (ECD) were assessed. Results: Eighteen eyes from 18 patients (mean age: 39.94 years) were included. Primary MPK indications were post-keratitis leucoma (77.7%), traumatic scarring (16.7%), and keratoconus (5.6%). At one year, mean BCVA improved significantly from 1.40 ± 0.42 logMAR to 0.46 ± 0.19 logMAR (p < 0.05), and mean CCT decreased from 721 ± 70.12 µm to 616 ± 52.80 µm (p < 0.05). The mean postoperative ECD was 1748 ± 100 cells/mm², with lower eye values requiring re-bubbling. No immunological rejection or graft failures were reported. Conclusions: nDSAEK is a promising treatment for MPK endothelial failure, demonstrating good visual and anatomical outcomes. Full article

Background: The use of lower limb prosthesis can impact all aspects of daily life, activities and participation. Various studies have compared the microprocessor-controlled knee (MPK) to the non-microprocessor-controlled knee (NMPK) using a variety of different outcome measures, but results are inconsistent and raise the question of which type of knee is most effective. Therefore, we aimed to assess the effect of MPKs compared to NMPKs across all classified ICF domains in adult prosthesis users. Methods: Participants performed baseline measurements with the NMPK (T0). One week later, they started a four-to-six-week trial period with the MPK. Afterward, measurements were repeated with the MPK (T1). Functional tests (6MWT, TUG-test and activity monitor) and questionnaires (ABC, SQUASH, USER-P and PEQ) were used. For statistical analyses, paired t-tests, Wilcoxon signed-rank tests and Chi² test were applied. The Benjamini–Hochberg procedure was applied to correct for multiple testing. Results: Twenty-five participants were included. Using an MPK compared to an NMPK significantly resulted in improvements in balance and walking confidence, safety, walking distance and self-reported walking ability, as well as a decrease in number of stumbles and falls. Additionally, participants using an MPK were significantly more satisfied with their participation, experienced fewer restrictions, reported greater satisfaction with the appearance and utility of the MPK, experienced less social burden and reported better well-being, compared to using an NMPK. Conclusions: Using an MPK instead of an NMPK can lead to significant improvements in all classified ICF domains, such as improved walking ability, confidence and satisfaction and reduced fall risk. Full article

Konjac glucomannan (KGM), derived from Amorphophallus konjac, is increasingly utilized in food and pharmaceutical applications. However, inconsistent KGM production across cultivars jeopardizes its quality and market viability. Lanthanum (La) has been shown to promote KGM levels, but the underlying mechanism remains unclear. In this study, 20~80 mg L⁻¹ La significantly stimulated KGM accumulation compared with the control group. We performed a transcriptome analysis and found 21,047 differentially expressed genes (DEGs), predominantly enriched in carbohydrate and glycan metabolism pathways. A total of 48 DEGs were linked to KGM biosynthesis, with 20 genes (SuSy, INV1/3/5/6, HK1/2, FPK2, GPI3, PGM3, UGP2, GMPP1/4, CslA3~7, CslH2, and MSR1.2) showing significant positive correlations with KGM content. Interestingly, three key terminal pathway genes (UGP1, UGP3, and CslD3) exhibited strong upregulation (log2 fold change > 3). Seven DEGs were validated with qRT-PCR, aligning with the transcriptomic results. Furthermore, 12 hormone-responsive DEGs, including 4 ethylene-related genes (CTR1, EBF1/2, EIN3, and MPK6), 6 auxin-related genes (AUX/IAA1-3, SAUR1-2, and TIR1), and 2 gibberellin-related genes (DELLA1-2), were closely linked to KGM levels. Additionally, the transcription factors bHLH and AP2/ERF showed to be closely related to the biosynthesis of KGM. These results lay the foundation for a model wherein La (Ш) modulates KGM accumulation by coordinately regulating biosynthetic and hormonal pathways via specific transcription factors. Full article

Bacterial wilt (BW) is a globally serious soil-borne disease in a wide range of plants, caused by diverse strains of Ralstonia solanacearum. However, there are few research reports on melatonin regulating plant resistance against R. solanacearum. N-acetyltransferase SlSNAT2 is a rate-limiting enzyme in plant melatonin synthesis. This study elucidates the mechanisms of SlSNAT2 modulating tomato resistance to BW. SlSNAT2 was expressed in tomato roots, stems, and leaves and induced upon R. solanacearum inoculation. Knocking out SlSNAT2 significantly decreased the melatonin content in CRISPR/Cas9 mutant slsnat2. With R. solanacearum inoculation, the morbidity and disease index value of slsnat2 were significantly higher than those of the tomato wild-type plant Micro-Tom (MT) according to the wilt rate and severity. The chlorophyll levels, photosynthetic rates, and callus deposition quantity in slsnat2 were notably lower while the reactive oxygen species (ROS) level was considerably higher than those in the MT after inoculation. Additionally, the SlSNAT2 deficiency depressed the expression of the mitogen-activated protein kinase (MAPK) pathway genes (SlMPK1, SlMKK2), salicylic acid pathway genes (SlGluA, SlPR-1a), jasmonic acid pathway gene SlPin2, and pathogenesis-related (PR) protein genes (SlPR-STH2a, SlPR-STH2b, SlPR-STH2c, SlPR-STH2d). These results revealed SlSNAT2 enhanced the tomato resistance against R. solanacearum by orchestrating ROS homeostasis, callose deposition, MAPK signaling, hormone pathways, and PR gene transcripts. Full article

Foxtail millet (Setaria italica), a significant C4 model crop known for its exceptional photosynthetic efficiency and robust environmental adaptability, serves as an excellent model for investigating C4 photosynthesis and crop stress resilience. When subjected to abiotic stress, foxtail millet employs a sophisticated signal transduction network to regulate its physiological processes, ensuring sustained high photosynthetic efficiency and normal growth. The mitogen-activated protein kinase (MAPK) family plays a key role in plant growth, development, and stress response. Here, we identified and named a MAPK in S. italica as SiMPK6. Fluorescence quantitative PCR analysis revealed that SiMPK6 is mainly expressed in the leaves during the early shooting stage, with induction under various abiotic stresses such as low temperature, high osmotic pressure, high salt, high temperature, and high light. Overexpressing the SiMPK6 in Arabidopsis thaliana mitigated damage to photosystem II induced by stress, underscoring the gene’s crucial role in foxtail millet’s stress signal transduction and maintenance of high photosynthetic efficiency. Full article

Leucine-rich repeat receptor-like kinases (LRR-RLKs) have evolved to perceive environmental changes. Among LRR-RLKs, PEPR1 perceives the pep1 peptide and triggers defense signal transduction in Arabidopsis thaliana. In the present study, we focused on PEPR1 and PEPR2, which are the receptors of pep1, to understand the role of tyrosine phosphorylation. PEPR1-CD (cytoplasmic domain) recombinant protein exhibited strong tyrosine autophosphorylation, including threonine autophosphorylation. We subjected all tyrosine residues in PEPR1-CD to site-directed mutagenesis. The recombinant proteins were purified along with PEPR1-CD, and Western blotting was performed using a tyrosine-specific antibody. Among the 13 tyrosine residues in PEPR1-CD, the PEPR1(Y995F)-CD recombinant protein showed significantly reduced tyrosine autophosphorylation intensity compared to PEPR1-CD and other tyrosine mutants, despite little change in threonine autophosphorylation. To confirm the autophosphorylation site, we generated a phospho-specific peptide Ab, pY995. As a result, Tyr-995 of PEPR1-CD was a major tyrosine autophosphorylation site in vitro. To understand the function of tyrosine phosphorylation in vivo, we generated transgenic plants, expressing PEPR1-Flag, PEPR1(Y995F)-Flag, and PEPR1(Y995D)-Flag in a pepr1/2 double mutant background. Interestingly, the root growths of PEPR1(Y995F)-Flag and PEPR1(Y995D)-Flag were not inhibited by pep1 peptide treatment, compared to Col-0 and PEPR1-Flag (pepr1/2) transgenic plants. Also, we analyzed downstream components, which included PROPEP1, MPK3, WRKY33, and RBOHD gene expressions in four different genotypes (Col-0, PEPR1-Flag, PEPR1(Y995F)-Flag, and PEPR1(Y995D)-Flag) of plants in the presence of the pep1 peptide. Interestingly, the expressions of PROPEP1, MPK3, WRKY33, and RBOHD were not regulated by pep1 peptide treatment in PEPR1(Y995F)-Flag and PEPR1(Y995D)-Flag transgenic plants, in contrast to Col-0 and PEPR1-Flag. These results suggest that specific tyrosine residues play an important role in vivo in the plant receptor function. Full article

Bamboo is a member of the Poaceae family and serves as an important economic resource with various applications, including reforestation, food production, and environmental conservation, due to its rapid growth and renewable nature. Among its various uses, bamboo shoots stand out for their tender texture and delicate flavor, making them a highly sought-after culinary delicacy in many cultures and a key ingredient in global food industries. Despite extensive research on the development of monopodial bamboos, studies focused on the developmental processes of sympodial bamboos, especially regarding their culinary potential, remain limited. This study conducted a comprehensive transcriptomic analysis of sympodial bamboo (Bambusa sp.) across six developmental stages (S1–S6) to uncover the molecular regulatory networks governing early bamboo shoot development. The results revealed that 1603 common differentially expressed genes (DEGs) across S1–S6 were enriched in multiple key pathways, with the most significant being plant hormone signaling, MAPK signaling, and Glycolysis/Gluconeogenesis pathways. Co-expression clustering analysis indicated that the Glycolysis/Gluconeogenesis pathway plays a crucial role during the later stages of bamboo shoot development (S5–S6), impacting its texture and flavor—two critical factors determining its culinary quality. Further Weighted Gene Co-expression Network Analysis (WGCNA) highlighted the significant role of the MAPK signaling pathway during early bamboo shoot development and identified key hub genes (MKK, MPK, MEKK) within this pathway, emphasizing their importance in cell division and hormonal coordination. This study provides valuable insights into the molecular mechanisms underlying the rapid growth and exceptional flavor of bamboo shoots and lays the foundation for the genetic improvement of bamboo as a sustainable and nutritious food source, enhancing its value as a premium food ingredient in the global market. Full article

The objective of this research was to investigate the efficacy of lotus leaf in the prevention and treatment of inflammatory diarrhea in pigs, utilizing network pharmacology and in vitro methodologies. Initially, LC-MS was employed to analyze the constituents of lotus leaf extract (LLE); then, the TCMSP database was utilized to identify the active components and their corresponding targets. The GeneCards database was consulted to identify disease-related targets pertinent to inflammatory diarrhea in pigs. A drug ingredient–disease target network was constructed using Cytoscape software. Subsequently, the STRING database facilitated protein interaction analysis, which was also visualized through Cytoscape. Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted based on the genes shared between disease and LLE targets. Molecular docking of the active ingredients with key targets was performed using Autodock Vina. Subsequently, an in vitro LPS-induced inflammation model was established using IPEC-J2 cells to validate the predictions made through network pharmacology. Verification was conducted via flow cytometry and Western blot analysis. The LC-MS assay and TCMSP retrieval results revealed that Quercetin, Nuciferine, Kaempferol, Leucodelphinidin, and Catechin were identified as the main compounds of LLE, associated with 181 potential targets. A total of 5995 targets were linked to inflammatory diarrhea in pigs, with 159 overlapping targets identified between the bioactive compounds and the disease. Notable key targets included TNF-α, IL-6, caspase-3, TP53, and AKT, which are integral to inflammation and apoptosis processes. GO functional annotation indicated significant enrichment in biological processes such as gene expression regulation and transcription from RNA polymerase II promoters. KEGG pathway analysis highlighted critical pathways, including TNF signaling and apoptosis. Furthermore, molecular docking analyses demonstrated that the bioactive components of lotus leaf exhibited a strong binding affinity for essential targets, including AKT1, BAX, caspase-3, CCL2, IL-6, IL-10, MPK14, NOS3, PTGS1, and TNF-α. In vitro experiments confirmed that LLE significantly inhibited LPS-induced apoptosis in IPEC-J2 cells and suppressed the activation of the TNF-α-mediated apoptosis pathway. This study offers novel insights into the therapeutic potential of Chinese medicine and its constituents in addressing inflammatory diarrhea in pigs. Full article

Blakeslea trispora is a key industrial strain for carotenoid production due to its rapid growth, ease of cultivation, and high yield. This study examined the effects of oxidative stress induced by rose bengal (RB) and hydrogen peroxide (H₂O₂) on carotenoid accumulation, achieving maximum yields of 459.38 ± 77.15 μg/g dry cell weight (DCW) at 0.4 g/L RB and 294.38 ± 14.16 μg/g DCW at 0.6% H₂O₂. These results demonstrate that oxidative stress promotes carotenoid accumulation in B. trispora. To investigate the underlying molecular mechanisms, transcriptional levels of key genes were analyzed under optimal stress conditions. In the carotenogenic pathway, only HMGR showed upregulation, while ACC, linked to fatty acid biosynthesis, remained unchanged. Within the mitogen-activated protein kinase (MAPK) pathway, FUS3 transcription increased under both stress conditions, MPK1 transcription rose only under H₂O₂ stress, and HOG1 exhibited no significant changes. Among heat shock proteins (HSPs), only HSP70 showed elevated transcription under H₂O₂ stress, while other HSP genes remained unchanged. These findings suggest that oxidative stress induced by RB and H₂O₂ enhances carotenoid accumulation in B. trispora through distinct regulatory pathways. This study provides valuable insights into stress-adaptive mechanisms and offers strategies to optimize carotenoid production in fungi. Full article

Puccinia polysora Underw, the pathogen that causes southern corn rust (SCR), delivers effectors to manipulate host immune responses. However, the mechanisms by which these effectors modulate host defenses are not well characterized. In this study, we found that the P. polysora effector PpEX is highly upregulated during infection. PpEX suppresses plant immune responses that are initiated by chitin, including the activation of mitogen-activated protein kinases (MAPKs) and the expression of pathogenesis-related (PR) genes. Maize plants transiently expressing PpEX exhibited higher pathogen infection rates, larger colony areas, and greater fungal biomass on their leaves compared to the control group. By employing TurboID proximity labeling technology coupled with mass spectrometry analysis, we discovered potential target proteins of PpEX in maize. The split-luciferase system enabled us to identify ZmMPK3, a component of the MAPK signaling pathway, as an interacting partner of PpEX among the candidate proteins. This interaction was subsequently confirmed by co-immunoprecipitation (Co-IP) experiments. Additionally, we verified that ZmMPK3 plays a positive role in regulating maize resistance to SCR. Thus, PpEX may function as a virulence effector that dampens plant PTI immunity by interacting with ZmMPK3 and impeding the MAPK signaling pathway. Full article

Extracellular vesicles (EVs) contain bioactive lipids that play a key role in pathophysiology. We hypothesized that EVs released from salt-loaded hypertensive diabetic db/db mice have increased bioactive lipid content that inhibits intracellular calcium mobilization and increases the activity of renal epithelial sodium channels (ENaC). An enrichment of sphingomyelins (SMs) was found in small urinary EVs (uEVs) isolated from salt-loaded hypertensive diabetic db/db mice (n = 4) compared to non-salt loaded db/db mice with diabetes alone (n = 4). Both groups of mice were included in the same cohort to control for variability. Cultured mouse cortical collecting duct (mpkCCD) cells loaded with a calcium reporter dye and challenged with small uEVs from hypertensive diabetic db/db mice showed a decrease in calcium mobilization when compared to cells treated with small uEVs from diabetic db/db mice. The amiloride-sensitive transepithelial current was increased in mpkCCD cells treated with small uEVs with abundant sphingomyelin content from hypertensive diabetic db/db mice in a dose- and time-dependent manner. Similar results were observed in mpkCCD cells and Xenopus 2F3 cells treated with exogenous sphingomyelin in a time-dependent manner. Single-channel patch clamp studies showed a decrease in ENaC activity in cells transiently transfected with sphingomyelin synthase 1/2 specific siRNA compared to non-targeting siRNA. These data suggest EVs with high sphingomyelin content positively regulate renal ENaC activity in a mechanism involving an inhibition of calcium mobilization. Full article

The balance between plant growth and stress response is a key issue in the field of biology. In this process, mitogen-activated protein kinase 3 (MPK3) and MPK6 contribute to the construction of plants’ defense system during stress tolerance, while auxin, a growth-promoting hormone, is the key to maintaining plant growth. Nevertheless, the antagonistic or cooperative relationship between MPK3/6-mediated stress response and auxin-mediated plant growth remains unclear. Here, we demonstrate that stress-activated MPK3/6 interact with the auxin signaling repressors indoleacetic acid-induced protein 8 (IAA8) and IAA9, two key targets for regulating the auxin signaling output during stress responses. Protein phosphorylation mass spectrometry followed by a co-analysis with in vitro phosphorylation experiments revealed that MPK3/6 phosphorylated the S91, T94, and S152 residues of IAA8 and the S88 residue of IAA9. Phosphorylation significantly enhanced the protein stability of IAA8/9, thereby maintaining basal auxin signaling during plant stress adaptation. Collectively, MPK3/6-IAA8/9 are key modules that are turned on during plant stress adaptation to precisely reduce auxin signaling output, thereby preventing plants from improper vigorous growth under stress conditions. Full article