Plants and animals respond to pathogens through pattern recognition receptor and Nod-like receptor proteins1. Pathogens commonly use protein effectors to suppress host immunity for successful infection2. However, the existence of non-protein effector classes remains comparatively understudied. Here we report an RNA-RNA recognition mechanism governing pathogen-host interaction, mediated by a regulatory RNA-encoding DNA sequence that separately generates two complementary regulatory RNAs. Specifically, a long non-coding RNA transcribed from this DNA region in the fungal pathogen Magnaporthe oryzae translocates into host rice cells and sequesters a complementary microRNA (miRNA), derived from a distinct host DNA region, thereby subverting host immunity. In turn, this rice-derived miRNA promotes disease resistance by repressing the expression of PKR1, a gene that encodes a negative regulator of host immunity. Sequestration of the host miRNA by the fungal long non-coding RNA releases PKR1 expression to facilitate fungal infection. We discovered that this regulatory RNA-encoding DNA sequence is probably widely present across diverse life species, mediating interactions between pathogens and their plant hosts. Collectively, our findings provide an approach for effective disease control using miRNAs derived from this important DNA region.
Post-translational modifications are crucial for regulating biological processes and stress responses in plants, yet oxidative modifications-particularly on methionine residues-remain largely unknown in the context of plant immunity. Previously, we identified the rice (Oryza sativa L.) transcription factor Broad-spectrum resistance Digu 1 (BSR-D1) as a key player in broad-spectrum blast resistance. Here, we report a mechanism by which a 14-3-3 protein, OsGF14d, interacts with BSR-D1 and promotes its oxidation at methionine 187 (M187) upon Magnaporthe oryzae infection. This oxidation enhances BSR-D1's DNA-binding affinity and transcriptional activity toward genes involved in hydrogen peroxide (H₂O₂) degradation, thereby modulating redox homeostasis and disease outcomes. Strikingly, knockout of OsGF14d increased H₂O₂ accumulation and strongly enhanced blast resistance without compromising plant growth. We further demonstrate that OsGF14d facilitates BSR-D1 oxidation through an acidic microenvironment created by residues Glu9, Glu50, and Glu51. Mutating M187 disrupted oxidative activation and diminished transcriptional output, underscoring the functional importance of this modification. Our findings reveal a regulatory layer in plant immunity, wherein pathogen-induced oxidative modification fine-tunes transcription factor activity. This study also positions OsGF14d as a promising target for breeding disease-resistant crops with maintained yield.
Although some lesion mimic mutants (LMMs) confer broad-spectrum disease resistance, their constitutive autoimmunity often penalizes plant growth and yield, limiting their application in crop breeding. Here, we report a novel strategy to overcome this trade-off in rice (Oryza sativa) by introducing a pathogen-inducible LMM gene variant, LRD6-6E315Q. We first found that constitutive expression of LRD6-6E315Q, a dominant-negative (DN) variant of the AAA-type ATPase gene LRD6-6, enhanced broad-spectrum resistance but inhibited plant growth, resembling the phenotype of the lrd6-6 mutant. To resolve this trade-off between disease resistance and growth, we screened a rice transcriptome and identified a rare inducible promoter, MIG6P that was specifically activated during early pathogen attack but maintained low activity under normal conditions, and was not inducible by abiotic stresses. We constructed a MIG6P:LRD6-6E315Q cassette, introduced it into rice cultivar TP309, and developed rice lines with enhanced resistance to multiple diseases, including bacterial blight and fungal diseases rice blast and sheath blight without affecting growth or yield. Since promoters analogous to MIG6P and protein homologs of AAA-type ATPase LRD6-6 carrying potential DN effects occur in diverse plant species, this strategy may be widely applicable to improve disease resistance in other crop species.
Background/objectiveTo investigate the effectiveness and safety of transarterial chemoembolization (TACE) plus percutaneous radiofrequency ablation (pRFA) (TACE-pRFA) for very early/early-stage hepatocellular carcinoma (HCC) with tumor diameters >3 cm versus ≤ 3 cm.MethodsIn this retrospective study, we enrolled 118 patients who underwent TACE-pRFA for a single HCC (≤ 5 cm) from February 2014 to December 2021. Patients were divided into two groups according to the maximum tumor diameter (≤ 3 cm versus > 3 cm). Regular follow-up was conducted after pRFA to assess progression-free survival (PFS). TACE-pRFA-related complications were evaluated. Univariable and multivariable Cox proportional-hazards regression analyses were performed to identify risk factors for PFS.ResultsThe median PFS of the total cohort was 35.0 months (95% confidence interval [CI], 24.3–45.7). The 1-, 3-, and 5-year cumulative PFS rates in the whole cohort were 84.7% (95% CI, 78.1–91.9%), 47.5% (95% CI, 38.2–59.0%), and 31.5% (95% CI, 22.2–44.9%), respectively. Univariable and multivariable analyses showed that the maximum tumor diameter (p = 0.023) was an independent prognostic factor for PFS after TACE-pRFA. Treatment-related complications were comparable between the ≤ 3 cm group and the > 3 cm group.ConclusionTACE combined with pRFA is safe for very early/early-stage single HCC ≤5 cm. Maximum tumor diameter is an independent prognostic factor for PFS, while treatment-related complications are comparable between tumors ≤3 cm and >3 cm.
Background:Liver cancer is a significant public health threat worldwide, yet data on its burden and trends are limited. This study aims to evaluate the global burden of liver cancer among global populations from 1990 to 2021, and to project its change to 2040. Methods:In this observational study, population-based registry data were extracted from the Global Burden of Diseases Study 2021. The database covers 204 countries and territories, ensuring global applicability of the results. Age-standardized rates of incidence, deaths, and disability-adjusted life-years (DALYs) were calculated per 100-000 population. Estimated rates of disease burden were calculated for 2040. Results:In 2021, global incident cases of liver cancer were 211460 (non-alcoholic steatohepatitis [NASH]-related), 1031830 (hepatitis B virus [HBV]-related), 770310 (hepatitis C virus [HCV]-related), 497720 (alcohol-related), 20240 (hepatoblastoma), and 114460 (other causes-related). HBV-related liver cancer exhibited the highest age-standardized rate of incidence (2.62 per 100-000 population; 95% uncertainty interval [UI], 2.15-3.19), deaths (2.30 per 100-000 population; 95% UI, 1.89-2.81), and DALYs (71.83 per 100-000 population; 95% UI, 59.65-87.25). In 2021, the 65-69 age group bore the heaviest burden, dominated by HBV-related cases. Higher sociodemographic indices correlated with greater burden for most subtypes. High-income Asia Pacific and East Asia had the highest regional burdens. Nationally, Mongolia, Taiwan (Province of China), Monaco, and Mali were most affected. Cross-country inequalities persisted. Projections to 2040 predict rising burden for all subtypes except hepatoblastoma, with NASH-related incident cases increasing by 51.97%. Conclusions:The global disease burden of all liver cancer subtypes, except hepatoblastoma, is increasing. There is an urgent need to strengthen interdisciplinary collaboration and integrate public health measures with clinical interventions to address the increasingly severe challenge of liver cancer.
The application of fungicides is an effective strategy for controlling plant diseases. Among these agents, plant-derived antifungal metabolites are particularly promising due to their eco-friendly and sustainable nature. Plant secondary metabolites typically exhibit broad-spectrum antifungal activity without selective toxicity against pathogens. However, only a small fraction of antifungal metabolites have been identified from the tens of thousands of known plant secondary metabolites. In this study, we conducted a metabolomic analysis on both blast-resistant (Digu) and -susceptible (Lijiangxintuanheigu) rice varieties to uncover novel metabolites that enhance blast resistance. We found that 24 and 48 h post-inoculation with Magnaporthe oryzae were critical time points for metabolomic profiling, based on the infected status of M. oryzae in rice and the observed differences in shikimate accumulation between the two varieties. Following metabolomic analysis, we identified nine flavonoids that were differentially accumulated and are considered potential candidates for disease control. Among these, apigenin-7-glucoside, rhamnetin, and spireoside were found to be effective in controlling blast disease, with spireoside demonstrating the most pronounced efficacy. We discovered that spireoside controlled blast disease by inhibiting both spore germination and appressorium formation in M. oryzae, primarily through disrupting cell membrane integrity. However, spireoside did not induce rice immunity. Furthermore, spireoside was also effective in controlling sheath blight disease. Thus, spireoside shows considerable promise as a candidate for the development of a fungicide for controlling plant diseases.
Global warming impacts crop production and increases crop disease. It is commonly known that heat stress (HS) caused by extreme high temperature induces HS responses but suppresses disease resistance in plants. However, the molecular basis of this trade-off remains largely unknown. Here, we report that OsHsfA4d shows strongest induction upon HS and pathogen infection among Heat Shock Factors (HSFs) in rice. The transcription factor OsHSFA4d enhances thermotolerance by binding to the heat shock element (HSE) in the promoter of HSP101 to activate its expression. OsHSFA4d also binds to the HSE in the first intron of Cellulose synthase-like F6 (CslF6) to promote its expression for suppressing PAMP-triggered ROS bursts and pathogenesis-related gene expression, inhibiting disease resistance. OsCDPK24 and OsCDPK28 interact with OsHSFA4d to form a complex that phosphorylates serine 146 (S146) of OsHSFA4d, thereby enhancing its DNA binding ability. HS induces the kinase activity of OsCDPK24/28 to increase the phosphorylation level of OsHSFA4d. Importantly, residues similar to S146 are conserved in OsHSFA4d orthologues across plant species, suggesting that such phosphorylation modules are widely employed to regulate abiotic and biotic stress responses in the plant kingdom.
The balance between the antagonistic traits, such as plant growth and disease resistance, is crucial for developing elite crop varieties. While the roles of plant hormones in this balance are well established, the regulatory function of secondary metabolites remains largely unexplored. Here, we report that 5-enolpyruvylshikimate-3-phosphate synthase (OsEPSPS), a key enzyme in the shikimate pathway, regulates both plant growth and disease resistance. Silencing the OsEPSPS gene in rice compromises the shikimate pathway but enhances the nicotinate and nicotinamide metabolism, resulting in the accumulations of trigonelline and nicotinamide mononucleotide (NMN). These metabolites boost resistance to rice blast by activating plant immune responses rather than inhibiting the germination and growth of Magnaporthe oryzae. Furthermore, silencing OsEPSPS conferring disease resistance results in less growth in plant. Our findings highlight the pivotal role of OsEPSPS in coordinating plant growth and disease resistance.
Hydrogen peroxide (H2O2) is a ubiquitous signal regulating many biological processes, including innate immunity, in all eukaryotes. However, it remains largely unknown that how transcription factors directly sense H2O2 in eukaryotes. Here, we report that rice basic/helix-loop-helix transcription factor bHLH25 directly senses H2O2 to confer resistance to multiple diseases caused by fungi or bacteria. Upon pathogen attack, rice plants increase the production of H2O2, which directly oxidizes bHLH25 at methionine 256 in the nucleus. Oxidized bHLH25 represses miR397b expression to activate lignin biosynthesis for plant cell wall reinforcement, preventing pathogens from penetrating plant cells. Lignin biosynthesis consumes H2O2 causing accumulation of non-oxidized bHLH25. Non-oxidized bHLH25 switches to promote the expression of Copalyl Diphosphate Synthase 2 (CPS2), which increases phytoalexin biosynthesis to inhibit expansion of pathogens that escape into plants. This oxidization/non-oxidation status change of bHLH25 allows plants to maintain H2O2, lignin and phytoalexin at optimized levels to effectively fight against pathogens and prevents these three molecules from over-accumulation that harms plants. Thus, our discovery reveals a novel mechanism by which a single protein promotes two independent defense pathways against pathogens. Importantly, the bHLH25 orthologues from available plant genomes all contain a conserved M256-like methionine suggesting the broad existence of this mechanism in the plant kingdom. Moreover, this Met-oxidation mechanism may also be employed by other eukaryotic transcription factors to sense H2O2 to change functions.
MYB transcription factors (TFs) play a critical role in plant immunity; however, their involvement in chaperone-mediated defense mechanisms remains unclear. Here, we demonstrated that MYB48 negatively regulates rice blast resistance by directly activating the heat shock protein gene HSP71.1. CRISPR/Cas9-generated MYB48 knockout lines exhibited enhanced resistance, with reduced lesion numbers and sizes, while overexpression lines displayed increased susceptibility. Nuclear-localized MYB48 directly binds to the HSP71.1 promoter to activate its transcription. Furthermore, knockout of HSP71.1 enhanced blast resistance. Notably, MYB48 knockout did not compromise agronomic traits, highlighting its potential for breeding applications. This study uncovers a novel MYB48-HSP71.1 regulatory module, linking MYB TFs to chaperone-mediated immunity, and provides dual targets for engineering blast-resistant rice.
Alternative splicing plays a vital role in plant immunity, but how plants stringently and selectively regulate alternative splicing to coordinate immunity and growth is poorly understood. Here, we report that H2O2-triggered phosphorylation of the RNA-binding protein RRM2R releases a retained-intron brake in OsMAPKKK18 encoding a mitogen-activated protein kinase kinase kinase to orchestrate plant immunity and growth in rice. We found that, without pathogen infection, OsMAPKKK18β transcripts containing a retained intron are subjected to nonsense-mediated mRNA decay to promote plant growth. Upon Magnaporthe oryzae pathogen invasion, H2O2 activates the protein kinase OsCLK1 to phosphorylate and stabilize RRM2R, which interacts with OsRNPS1A/B to recruit spliceosome machinery and promote the production of OsMAPKKK18α transcripts without the retained intron to promote rice immunity. Furthermore, we revealed that after the endogenous H2O2 is consumed or degraded by peroxidases or catalases, decreased abundance of RRM2R reduces the accumulation of OsMAPKKK18α transcripts to avoid autoimmunity in rice. Taken together, the results of our study uncover H2O2-controlled OsMAPKKK18 intron retention as a novel molecular switch for orchestrating immunity and growth in rice.
The infection cycle of Magnaporthe oryzae (M. oryzae) in rice typically involves initial invasion through penetration of the leaf epidermis, followed by expansion into neighboring cells. However, few studies have identified single genes that mediate defense against both invasion and expansion. In this study, we demonstrate that OsWRKY47 positively regulates resistance to both stages of M. oryzae infection. Mechanistic analyses indicate that OsWRKY47 transcriptionally activates OsMYB30 during the early stage, thereby enhancing lignin accumulation and strengthening physical barriers against fungal invasion. At later stages, OsWRKY47 represses OsWRKY39 expression, thereby inhibiting M. oryzae expansion. Knockout of OsWRKY39 leads to increased accumulation of stevioside, a metabolite that activates plant immune responses, representing a chemical defense strategy. Structure-function analyses further reveal that a region comprising amino acids 282-288 of OsWRKY47 is crucial for the positive regulation of OsMYB30, whereas the region comprising amino acids 303-333 is essential for repression of OsWRKY39. Collectively, these findings reveal an OsWRKY47-OsMYB30/OsWRKY39 regulatory module that confers resistance to M. oryzae by coordinating physical and chemical defenses to restrict pathogen invasion and expansion. Such coordinated activation of physical and chemical defenses may represent a widespread strategy in plant pathogen responses.
Background/objectiveThe aim of this study was to evaluate tumor progression and recurrence patterns of radiofrequency ablation (RFA) with or without transarterial chemoembolization (TACE) for treating hepatocellular carcinoma (HCC) that meets Milan criteria.MethodsThis retrospective study included consecutive HCC patients meeting Milan criteria who underwent percutaneous RFA with or without TACE as initial treatment at a tertiary academic center between December 2017 and 2022. Technical success rate, local recurrence-free survival (LRFS), progression-free survival (PFS) and recurrence patterns were recorded.ResultsA total of 135 HCC patients (109 male [80.7%]) with a mean age of 62 years and 147 target lesions were retrospectively enrolled. The technical success rate was 99.3%. The median LRFS was 60 months, and the cumulative 1-, 3-, and 5-year LRFS were 88.9%, 70.1%, and 30.0%, respectively. Additionally, the median PFS was 23 months, with cumulative 1-, 3-, and 5-year PFS of 74%, 30%, and 0%, respectively. Multivariate analysis confirmed that age > 60, alpha-fetoprotein (AFP) (> 10), and albumin were associated with PFS (2.34, p = 0.004; 1.96, p = 0.021; 0.94, p = 0.007, respectively). Six recurrence patterns were identified: local tumor progression (LTP) alone (n = 15, 25.0%), intrahepatic distant recurrence (IDR) alone (n = 34, 56.7%), extrahepatic recurrence (ER) alone (n = 2, 3.3%), IDR + ER (n = 2, 3.3%), LTP + IDR (n = 5, 8.8%), and LTP + IDR + ER (n = 2, 3.3%). IDR occurred most frequently as a sign of good local treatment.ConclusionsRFA in combination with TACE does not appear to provide an advantage over RFA alone in improving tumor progression in patients with HCC meeting the Milan criteria. However, further prospective studies are needed to confirm these findings and to determine the optimal treatment approach for this patient population.
Bone cancer pain (BCP) represents a prevalent symptom among cancer patients with bone metastases, yet its underlying mechanisms remain elusive. This study investigated the transcriptional regulation mechanism of Kv7(KCNQ)/M potassium channels in DRG neurons and its involvement in the development of BCP in rats. We show that HDAC2-mediated transcriptional repression of kcnq2/kcnq3 genes, which encode Kv7(KCNQ)/M potassium channels in dorsal root ganglion (DRG), contributes to the sensitization of DRG neurons and the pathogenesis of BCP in rats. Also, HDAC2 requires the formation of a corepressor complex with MeCP2 and Sin3A to execute transcriptional regulation of kcnq2/kcnq3 genes. Moreover, EREG is identified as an upstream signal molecule for HDAC2-mediated kcnq2/kcnq3 genes transcription repression. Activation of EREG/EGFR-ERK-Runx1 signaling, followed by the induction of HDAC2-mediated transcriptional repression of kcnq2/kcnq3 genes in DRG neurons, leads to neuronal hyperexcitability and pain hypersensitivity in tumor-bearing rats. Consequently, the activation of EREG/EGFR-ERK-Runx1 signaling, along with the subsequent transcriptional repression of kcnq2/kcnq3 genes by HDAC2 in DRG neurons, underlies the sensitization of DRG neurons and the pathogenesis of BCP in rats. These findings uncover a potentially targetable mechanism contributing to bone metastasis-associated pain in cancer patients.
The Ideal Plant Architecture 1 (IPA1) transcription factor promotes rice yield and immunity through phosphorylation at its amino acid residue Ser163 as a switch. Although phosphorylated IPA1 mimic, IPA1(S163D), directly targets the promoter of immune response gene WRKY45, it cannot activate its expression. Here, we identified a co-activator of IPA1(S163D), a RING-finger E3 ligase IPA1 interactor 7 (IPI7), which fine-tunes the transcriptional activity of IPA1 to timely promote plant immunity and simultaneously maintain growth for yield. IPI7 interacts with IPA1 and promotes K29-polyubiquitination of IPA1 in vitro and in vivo. However, the stability of IPA1 protein is not affected by IPI7-mediated ubiquitination. The IPI7-promoted K29-polyubiquitination of IPA1 is induced by Magnaporthe oryzae infection and required for phosphorylated IPA1 to transactivate WRKY45 expression for immune response but not for plain IPA1 to transactivate DENSE AND ERECT PANICLES 1 (DEP1) expression for panicle development. IPI7 knockout impairs IPA1-mediated immunity but not yield. Our study reveals that plants utilize non-proteolytic K29-ubiquitination as a response to pathogen infection to fine-tune IPA1 transactivation activity for promoting immunity.
Background/ObjectiveTreatment of hepatocellular carcinoma (HCC) with ablation alone often results in high rates of recurrence and metastasis, reaching up to 25.9% within two years. Therefore, this study aimed to examine the efficacy and safety of transarterial chemoembolization (TACE)-assisted multi-image guided radiofrequency ablation (RFA) for the treatment of stage Ia HCC according to the China liver cancer staging (CNLC).MethodsThis study enrolled and analyzed a total of 118 patients diagnosed with HCC, each with a single nodular lesion no larger than 5 cm, who received TACE-RFA as first-line therapy between February 1, 2014, and December 31, 2021. The median/mean follow-up period was 29.0 months [95% confidence interval (CI): 21.8-36.2 months] and 31.8 months (95% CI: 27.5-36.0 months), respectively. We assessed the treatment’s effectiveness, potential complications, and survival rate.ResultsThe technical success rate was 100% (118/118) after the initial treatment. Out of the total, 3 out of 118 patients (2.5%) developed local tumor progression (LTP) during the follow-up period. The median time for LTP was 29.0 months (95%CI: 21.9-36.1 months; mean: 31.5 months; range 1-92 months). At 1, 3, 5, and 7 years after treatment, the cumulative LTP rates were 0%, 4.6%, 4.6%, and 4.6%, respectively. The overall survival rates at 1, 3, 5, and 7 years were 100%, 95.2%, 95.2%, and 95.2%, respectively. In total, 28 patients experienced minor Grade B complications, and no major complications or treatment-related mortality occurred.ConclusionThe treatment of CNLC stage Ia HCC using TACE-assisted multi-image-guided RFA was found to be both safe and feasible.
Fungal pathogens typically use secreted effector proteins to suppress host immune activators to facilitate invasion. However, there is rarely evidence supporting the idea that fungal secretory proteins contribute to pathogenesis by transactivating host genes that suppress defense. We previously found that pathogen Magnaporthe oryzae induces rice Bsr-d1 to facilitate infection and hypothesized that a fungal effector mediates this induction. Here, we report that MoSPAB1 secreted by M. oryzae directly binds to the Bsr-d1 promoter to induce its expression, facilitating pathogenesis. Amino acids 103-123 of MoSPAB1 are required for its binding to the Bsr-d1 promoter. Both MoSPAB1 and rice MYBS1 compete for binding to the Bsr-d1 promoter to regulate Bsr-d1 expression. Furthermore, MoSPAB1 homologues are highly conserved among fungi. In particular, Colletotrichum fructicola CfSPAB1 and Colletotrichum sublineola CsSPAB1 activate kiwifruit AcBsr-d1 and sorghum SbBsr-d1 respectively, to facilitate pathogenesis. Taken together, our findings reveal a conserved module that may be widely utilized by fungi to enhance pathogenesis.
Purpose To compare the long-term outcomes of combined transarterial chemoembolization and radiofrequency ablation (TACE-RFA) with radiofrequency ablation (RFA) monotherapy for small (<= 3 cm) hepatocellular carcinomas (HCCs). Methods A total of 248 patients with 329 HCC nodules who underwent TACE-RFA or RFA monotherapy as the only first-line treatment between January 2009 and December 2020 were included in this study. The technical success, complications, survival rate, and local tumor progression (LTP) rate were compared between the two treatments. Results The 1-, 3- and 5-year survival rates were similar between the two groups (98.7%, 93.0% and 75.9% vs 97.4%, 88.0% and 77.4%; p = 0.444). The 1-, 3-, and 5-year cumulative LTP rates were significantly lower in the TACE-RFA group than in the RFA monotherapy group (2.9%, 9.2%, and 13.8% vs. 5.2%, 17.0%, and 21.0%; p = 0.043). Subgroup analyses suggested that TACE-RFA showed significantly lower LTP rates than RFA monotherapy for small HCC with tumor size>2cm (p = 0.008), subphrenic location (p = 0.021), and perivessel (p = 0.030). Furthermore, HCC with well-defined lipiodol deposition in the TACE-RFA group showed better local tumor control than the small HCC in the RFA monotherapy group (p = 0.013). There was no significant difference in the technical success rates (p = 0.064) and complication rates (p = 0.952) between the two groups. Conclusions TACE-RFA is superior to RFA monotherapy in providing local tumor control for small HCC with tumor size 2-3 cm in diameter, subphrenic location, perivessel and HCCs with well-defined lipiodol deposition by TACE before RFA.