RESUMEN
Plants protect themselves with a vast array of toxic secondary metabolites, yet most plants serve as food for insects. The evolutionary processes that allow herbivorous insects to resist plant defenses remain largely unknown. The whitefly Bemisia tabaci is a cosmopolitan, highly polyphagous agricultural pest that vectors several serious plant pathogenic viruses and is an excellent model to probe the molecular mechanisms involved in overcoming plant defenses. Here, we show that, through an exceptional horizontal gene transfer event, the whitefly has acquired the plant-derived phenolic glucoside malonyltransferase gene BtPMaT1. This gene enables whiteflies to neutralize phenolic glucosides. This was confirmed by genetically transforming tomato plants to produce small interfering RNAs that silence BtPMaT1, thus impairing the whiteflies' detoxification ability. These findings reveal an evolutionary scenario whereby herbivores harness the genetic toolkit of their host plants to develop resistance to plant defenses and how this can be exploited for crop protection.
Asunto(s)
Hemípteros/genética , Proteínas de Insectos/metabolismo , Solanum lycopersicum/genética , Toxinas Biológicas/metabolismo , Animales , Transferencia de Gen Horizontal , Genes de Plantas , Glucósidos/química , Glucósidos/metabolismo , Hemípteros/fisiología , Herbivoria , Proteínas de Insectos/antagonistas & inhibidores , Proteínas de Insectos/clasificación , Proteínas de Insectos/genética , Mucosa Intestinal/metabolismo , Solanum lycopersicum/metabolismo , Malonil Coenzima A/metabolismo , Filogenia , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Interferencia de ARN , ARN Bicatenario/metabolismo , Toxinas Biológicas/químicaRESUMEN
Ongoing host-pathogen interactions can trigger a coevolutionary arms race, while genetic diversity within the host can facilitate its adaptation to pathogens. Here, we used the diamondback moth (Plutella xylostella) and its pathogen Bacillus thuringiensis (Bt) as a model for exploring an adaptive evolutionary mechanism. We found that insect host adaptation to the primary Bt virulence factors was tightly associated with a short interspersed nuclear element (SINE - named SE2) insertion into the promoter of the transcriptionally activated MAP4K4 gene. This retrotransposon insertion coopts and potentiates the effect of the transcription factor forkhead box O (FOXO) in inducing a hormone-modulated Mitogen-activated protein kinase (MAPK) signaling cascade, leading to an enhancement of a host defense mechanism against the pathogen. This work demonstrates that reconstructing a cis-trans interaction can escalate a host response mechanism into a more stringent resistance phenotype to resist pathogen infection, providing a new insight into the coevolutionary mechanism of host organisms and their microbial pathogens.
Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Animales , Endotoxinas/farmacología , Retroelementos/genética , Mariposas Nocturnas/metabolismo , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis/metabolismo , Resistencia a los Insecticidas/genética , Larva/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Hemolisinas/metabolismoRESUMEN
The neurobiological understanding of obsessive-compulsive disorder (OCD) includes dysregulated frontostriatal circuitry and altered monoamine transmission. Repetitive stereotyped behavior (e.g., grooming), a featured symptom in OCD, has been proposed to be associated with perturbed dopamine (DA) signaling. However, the precise brain circuits participating in DA's control over this behavioral phenotype remain elusive. Here, we identified that DA neurons in substantia nigra pars compacta (SNc) orchestrate ventromedial striatum (VMS) microcircuits as well as lateral orbitofrontal cortex (lOFC) during self-grooming behavior. SNc-VMS and SNc-lOFC dopaminergic projections modulate grooming behaviors and striatal microcircuit function differentially. Specifically, the activity of the SNc-VMS pathway promotes grooming via D1 receptors, whereas the activity of the SNc-lOFC pathway suppresses grooming via D2 receptors. SNc DA neuron activity thus controls the OCD-like behaviors via both striatal and cortical projections as dual gating. These results support both pharmacological and brain-stimulation treatments for OCD.
Asunto(s)
Neuronas Dopaminérgicas , Trastorno Obsesivo Compulsivo , Animales , Neuronas Dopaminérgicas/metabolismo , Cuerpo Estriado/fisiología , Dopamina/metabolismo , Mesencéfalo/metabolismo , Sustancia Negra/metabolismoRESUMEN
The benefits of biopesticides and transgenic crops based on the insecticidal Cry-toxins from Bacillus thuringiensis (Bt) are considerably threatened by insect resistance evolution, thus, deciphering the molecular mechanisms underlying insect resistance to Bt products is of great significance to their sustainable utilization. Previously, we have demonstrated that the down-regulation of PxmALP in a strain of Plutella xylostella (L.) highly resistant to the Bt Cry1Ac toxin was due to a hormone-activated MAPK signaling pathway and contributed to the resistance phenotype. However, the underlying transcriptional regulatory mechanism remains enigmatic. Here, we report that the PxGATAd transcription factor (TF) is responsible for the differential expression of PxmALP observed between the Cry1Ac susceptible and resistant strains. We identified that PxGATAd directly activates PxmALP expression via interacting with a non-canonical but specific GATA-like cis-response element (CRE) located in the PxmALP promoter region. A six-nucleotide insertion mutation in this cis-acting element of the PxmALP promoter from the resistant strain resulted in repression of transcriptional activity, affecting the regulatory performance of PxGATAd. Furthermore, silencing of PxGATAd in susceptible larvae reduced the expression of PxmALP and susceptibility to Cry1Ac toxin. Suppressing PxMAP4K4 expression in the resistant larvae transiently recovered both the expression of PxGATAd and PxmALP, indicating that the PxGATAd is a positive responsive factor involved in the activation of PxmALP promoter and negatively regulated by the MAPK signaling pathway. Overall, this study deciphers an intricate regulatory mechanism of PxmALP gene expression and highlights the concurrent involvement of both trans-regulatory factors and cis-acting elements in Cry1Ac resistance development in lepidopteran insects.
Asunto(s)
Toxinas de Bacillus thuringiensis/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Resistencia a los Insecticidas/genética , Sistema de Señalización de MAP Quinasas/fisiología , Animales , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis/farmacología , Proteínas Bacterianas/genética , Endotoxinas/farmacología , Granulovirus/genética , Proteínas Hemolisinas/farmacología , Proteínas de Insectos/genética , Insecticidas/metabolismo , Larva/genética , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismo , Factores de Transcripción/genéticaRESUMEN
Host-pathogen interactions are central components of ecological networks where the MAPK signaling pathways act as central hubs of these complex interactions. We have previously shown that an insect hormone modulated MAPK signaling cascade participates as a general switch to trans-regulate differential expression of diverse midgut genes in the diamondback moth, Plutella xylostella (L.) to cope with the insecticidal action of Cry1Ac toxin, produced by the entomopathogenic bacterium Bacillus thuringiensis (Bt). The relationship between topology and functions of this four-tiered phosphorylation signaling cascade, however, is an uncharted territory. Here, we carried out a genome-wide characterization of all the MAPK orthologs in P. xylostella to define their phylogenetic relationships and to confirm their evolutionary conserved modules. Results from quantitative phosphoproteomic analyses, combined with functional validations studies using specific inhibitors and dsRNAs lead us to establish a MAPK "road map", where p38 and ERK MAPK signaling pathways, in large part, mount a resistance response against Bt toxins through regulating the differential expression of multiple Cry toxin receptors and their non-receptor paralogs in P. xylostella midgut. These data not only advance our understanding of host-pathogen interactions in agricultural pests, but also inform the future development of biopesticides that could suppress Cry resistance phenotypes.
Asunto(s)
Infecciones por Bacterias Grampositivas/metabolismo , Interacciones Huésped-Patógeno/fisiología , Sistema de Señalización de MAP Quinasas/fisiología , Mariposas Nocturnas/metabolismo , Mariposas Nocturnas/microbiología , Animales , Bacillus thuringiensis , Toxinas de Bacillus thuringiensis/metabolismo , Endotoxinas/metabolismo , Infecciones por Bacterias Grampositivas/veterinaria , Proteínas Hemolisinas/metabolismo , Resistencia a los InsecticidasRESUMEN
The whitefly Bemisia tabaci is a piercing-sucking herbivore that reduces the yields of crops both by feeding on plants and transmitting plant viruses. Like most plant feeders, B. tabaci has evolved ways to avoid plant defence responses. For example, B. tabaci is known to secrete salivary effectors to suppress host defences. However, the nature of B. tabaci effectors is not completely understood. In this study, we used B. tabaci genomic and salivary gland transcriptomic data and an overexpression system to identify a previously unknown B. tabaci salivary effector, BtE3. BtE3 is specifically expressed in the head (containing primary salivary glands) and is secreted into hosts during B. tabaci feeding. In planta overexpression of BtE3 blocked Burkholderia glumae-induced hypersensitive response (HR) in both Nicotiana benthamiana and Solanum lycopersicum. Silencing of BtE3 by plant-mediated RNAi prevented B. tabaci from continuously ingesting phloem sap, and reduced B. tabaci survival and fecundity. Moreover, overexpression of BtE3 in planta up-regulated the salicylic acid- (SA-) signalling pathway, but suppressed the downstream jasmonic acid- (JA-) mediated defences. Taken together, these results indicate that BtE3 is a B. tabaci-specific novel effector involved in B. tabaci-plant interactions. These findings increase our understanding of B. tabaci effectors and suggest novel strategies for B. tabaci pest management.
Asunto(s)
Hemípteros , Solanum lycopersicum , Animales , Hemípteros/fisiología , Nicotiana/genética , Transducción de Señal , Solanum lycopersicum/genética , Productos AgrícolasRESUMEN
BACKGROUND: Drug resistance in Helicobacter pylori severely affects the efficacy of eradication therapy, and a number of studies have been conducted on this issue. The aim of this study was to assess the progress in this field using a bibliometric approach. MATERIALS AND METHODS: Publications related to H. pylori resistance from 2002 to 2022 were retrieved from the Web of Science database. Relevant information including titles, authors, countries, and keywords was extracted, and the data were processed using Excel, VOSviewer, and CiteSpace software for co-authorship, co-citation, and co-occurrence analysis. RESULTS: From 2002 to 2022 (as of 09/24/2022), the field of H. pylori-resistance research produced a total of 2677 publications with a total of 75217 citations, with an overall upward trend in the annual number of articles published, reaching a peak of 204 in 2019. Articles were mainly published in Q1 or Q2 journals, with Helicobacter (TP = 261) publishing the most literature, Baylor College of Medicine (TP = 68) and Deng-chyang wu (TP = 38) being the most prolific institutions and authors, respectively. China and the United States were the locations of most of the articles, accounting for 35.08% of the global publication volume. Keyword co-occurrence analysis divided H. pylori-resistance research into four clusters: "Therapeutic Strategies," "Diseases," "Mechanism Research and Epidemiology," and "Drug Research." "Drug research" and burst detection indicate that the current research hotspot involves the selection and analysis of treatment strategies. CONCLUSIONS: H. pylori-resistance research has become a popular research field, and although there are significant contributions from Europe, the United States, and East Asia, there are significant imbalances between regions that cannot be ignored. In addition, the exploration of treatment strategies remains a key issue for research at the current stage.
Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Helicobacter , Humanos , Helicobacter pylori/genética , Infecciones por Helicobacter/tratamiento farmacológico , Bibliometría , ChinaRESUMEN
BACKGROUND: Hepatitis C virus (HCV) can be transmitted by blood transfusion. The aim of this meta-analysis is to estimate the anti-HCV reactive rate and to define the demographic characteristics of blood donors who have potential threats to blood safety in mainland China for nearly 30 years, in order to provide a safe reference for blood transfusion and corresponding guidance for policymakers to increase blood safety. MATERIALS AND METHODS: Literature reporting the anti-HCV screening reactive rate in Chinese blood donors was identified by systematic searching of four electronic databases from 1991 to 2017. The Preferred Reporting of Items for Systematic Reviews and Meta-Analyses guidelines were strictly followed, and data manipulation and statistical analysis were performed by Stata 15.0. RESULTS: Our results showed that the post-donation anti-HCV reactive rate was 0.53% (95% confidence interval [CI], 0.51%-0.55%) with a significant variation from 1.58% (95% CI, 1.13%-2.03%) before 1998 to 0.51% (95% CI, 0.48%-0.53%) after 1998 when the Blood Donation Law was implemented in China. In addition, anti-HCV screening reactive rate for family or replacement donors was significantly higher than that in individual voluntary blood donors. CONCLUSION: Our results indicated that blood centres in China should convert more eligible first-time donors into repeat donors and turn the 'real family or replacement donors' into individual voluntary blood donors to reduce the risk of transfusion-transmitted HCV. In the meantime, large surveys should be carried out among volunteer donors from high-risk populations.
Asunto(s)
Hepacivirus , Hepatitis C , Humanos , Donantes de Sangre , Hepatitis C/diagnóstico , Hepatitis C/epidemiología , Factores de Riesgo , China , AnticuerposRESUMEN
The evolution of insect resistance to pesticides poses a continuing threat to agriculture and human health. While much is known about the proximate molecular and biochemical mechanisms that confer resistance, far less is known about the regulation of the specific genes/gene families involved, particularly by trans-acting factors such as signal-regulated transcription factors. Here we resolve in fine detail the trans-regulation of CYP6CM1, a cytochrome P450 that confers resistance to neonicotinoid insecticides in the whitefly Bemisia tabaci, by the mitogen-activated protein kinase (MAPK)-directed activation of the transcription factor cAMP-response element binding protein (CREB). Reporter gene assays were used to identify the putative promoter of CYP6CM1, but no consistent polymorphisms were observed in the promoter of a resistant strain of B. tabaci (imidacloprid-resistant, IMR), which overexpresses this gene, compared to a susceptible strain (imidacloprid-susceptible, IMS). Investigation of potential trans-acting factors using in vitro and in vivo assays demonstrated that the bZIP transcription factor CREB directly regulates CYP6CM1 expression by binding to a cAMP-response element (CRE)-like site in the promoter of this gene. CREB is overexpressed in the IMR strain, and inhibitor, luciferase, and RNA interference assays revealed that a signaling pathway of MAPKs mediates the activation of CREB, and thus the increased expression of CYP6CM1, by phosphorylation-mediated signal transduction. Collectively, these results provide mechanistic insights into the regulation of xenobiotic responses in insects and implicate both the MAPK-signaling pathway and a transcription factor in the development of pesticide resistance.
Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Resistencia a Medicamentos/genética , Regulación de la Expresión Génica , Hemípteros/crecimiento & desarrollo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Neonicotinoides/farmacología , Nitrocompuestos/farmacología , Animales , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Sistema Enzimático del Citocromo P-450/genética , Hemípteros/efectos de los fármacos , Hemípteros/genética , Hemípteros/metabolismo , Insecticidas/farmacología , Proteínas Quinasas Activadas por Mitógenos/genética , Mutación , Fosforilación , Regiones Promotoras GenéticasRESUMEN
The rapid evolution of pest resistance threatens the sustainable utilization of bioinsecticides such as abamectin, and so deciphering the molecular mechanisms affecting toxicity and resistance is essential for their long-term application. Historical studies of abamectin resistance in arthropods have mainly focused on mechanisms involving the glutamate-gated chloride channel (GluCl) targets, with the role of metabolic processes less clear. The two-spotted spider mite, Tetranychus urticae, is a generalist herbivore notorious for rapidly developing resistance to pesticides worldwide, and abamectin has been widely used for its control in the field. After reanalyzing previous transcriptome and RNA-seq data, we here identified an ABC transporter subfamily C gene in T. urticae named multidrug resistance-associated protein 1 (TuMRP1), whose expression differed between susceptible and resistant populations. Synergism bioassays with the inhibitor MK-571, the existence of a genetic association between TuMRP1 expression and susceptibility to abamectin, and the effect of RNA interference mediated silencing of TuMRP1 were all consistent with a direct role of this transporter protein in the toxicity of abamectin. Although ABC transporters are often involved in removing insecticidal compounds from cells, our data suggest either an alternative role for these proteins in the mechanism of action of abamectin or highlight an indirect association between their expression and abamectin toxicity.
Asunto(s)
Tetranychidae , Animales , Tetranychidae/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Ivermectina/toxicidadRESUMEN
BACKGROUND: Biopesticides and transgenic crops based on Bacillus thuringiensis (Bt) toxins are extensively used to control insect pests, but the rapid evolution of insect resistance seriously threatens their effectiveness. Bt resistance is often polygenic and complex. Mutations that confer resistance occur in midgut proteins that act as cell surface receptors for the toxin, and it is thought they facilitate its assembly as a membrane-damaging pore. However, the mechanistic details of the action of Bt toxins remain controversial. RESULTS: We have examined the contribution of two paralogous ABC transporters and two aminopeptidases N to Bt Cry1Ac toxicity in the diamondback moth, Plutella xylostella, using CRISPR/Cas9 to generate a series of homozygous polygenic knockout strains. A double-gene knockout strain, in which the two paralogous ABC transporters ABCC2 and ABCC3 were deleted, exhibited 4482-fold resistance to Cry1A toxin, significantly greater than that previously reported for single-gene knockouts and confirming the mutual functional redundancy of these ABC transporters in acting as toxin receptors in P. xylostella. A double-gene knockout strain in which APN1 and APN3a were deleted exhibited 1425-fold resistance to Cry1Ac toxin, providing the most direct evidence to date for these APN proteins acting as Cry1Ac toxin receptors, while also indicating their functional redundancy. Genetic crosses of the two double-gene knockouts yielded a hybrid strain in which all four receptor genes were deleted and this resulted in a > 34,000-fold resistance, indicating that while both types of receptor need to be present for the toxin to be fully effective, there is a level of functional redundancy between them. The highly resistant quadruple knockout strain was less fit than wild-type moths, but no fitness cost was detected in the double knockout strains. CONCLUSION: Our results provide direct evidence that APN1 and APN3a are important for Cry1Ac toxicity. They support our overarching hypothesis of a versatile mode of action of Bt toxins, which can compensate for the absence of individual receptors, and are consistent with an interplay among diverse midgut receptors in the toxins' mechanism of action in a super pest.
Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/toxicidad , Antígenos CD13/genética , Antígenos CD13/metabolismo , Endotoxinas/genética , Endotoxinas/toxicidad , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/toxicidad , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Resistencia a los Insecticidas/genética , Larva/genética , Mariposas Nocturnas/genéticaRESUMEN
OBJECTIVE: To compare the recurrence rate of retinopathy of prematurity (ROP) after treatment with 0.3 mg vs. 0.25 mg ranibizumab. SUBJECTS: All patients with ROP who underwent intravitreal injection of ranibizumab in Hainan General Hospital between January 2014 and May 2020 were included in this retrospective study. METHODS: Eighty-two cases (146 eyes) who received intravitreal injection of 0.25 mg ranibizumab were included in the conventional-dose group, and 59 cases (108 eyes) who received intravitreal injection of 0.3 mg ranibizumab were included in the high-dose group. The two groups were further divided into the 25-28-week, 29-31-week, 32-34-week, and 35-36-week GA subgroups. The differences between the conventional-dose group and the high-dose group in gestational age (GA), birth weight (BW), age at initial injection (weeks), incidence of systemic diseases, the recurrence rate of ROP, and age at retinal vascularization completed (weeks) were analyzed. RESULTS: GA, BW, age at initial injection, and the incidence of systemic diseases were not significantly different between the conventional-dose group and the high-dose group (p > 0.05). The recurrence rates of ROP were significantly lower in the 25-28-week, 29-31-week, and 32-34-week subgroups of the high-dose group than in the same subgroups of the conventional-dose group (p < 0.05). Within the conventional-dose group, the recurrence rate of ROP was significantly lower in the 32-34-week and 35-36-week subgroups than in the 25-28-week and 29-31-week subgroups (p < 0.05). Within the high-dose group, the recurrence rate of ROP was not significantly different between the four subgroups (p > 0.05). Retinal vascularization was completed at a later age in the 32-34-week subgroup of the high-dose group than in the 32-34-week subgroup of the conventional-dose group (p < 0.05) but was not significantly different between the two groups at any other GA range (p > 0.05). No severe ocular or systemic complications occurred in any patient. CONCLUSION: Treatment with 0.3 mg ranibizumab can reduce the recurrence rate of ROP without prolonging retinal vascularization or causing serious systemic complications. Therefore, this dose may be an appropriate therapeutic dose for ROP.
Asunto(s)
Neovascularización Retiniana , Retinopatía de la Prematuridad , Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab/uso terapéutico , Edad Gestacional , Humanos , Recién Nacido , Inyecciones Intravítreas , Ranibizumab/uso terapéutico , Neovascularización Retiniana/tratamiento farmacológico , Retinopatía de la Prematuridad/epidemiología , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Deciphering the molecular mechanisms of insect resistance to Bacillus thuringiensis (Bt) based biotechnology products including Bt sprays and Bt crops is critical for the long-term application of Bt technology. Previously, we established that down-regulation of the ABC transporter gene PxABCG1, trans-regulated by the MAPK signaling pathway, contributed to high-level resistance to Bt Cry1Ac toxin in diamondback moth, Plutella xylostella (L.). However, the underlying transcriptional regulatory mechanism was unknown. Herein, we identified putative binding sites (PBSs) of the transcription factor (TF) POUM1 in the PxABCG1 promoter and used a dual-luciferase reporter assay (DLRA) and yeast one-hybrid (Y1H) assay to reveal that POUM1 activates PxABCG1 via interaction with one of these sites. The expression of POUM1 was significantly decreased in the midgut tissue of Cry1Ac-resistant P. xylostella strains compared to a Cry1Ac-susceptible P. xylostella strain. Silencing of POUM1 expression resulted in reduced expression of the PxABCG1 gene and an increase in larval tolerance to Bt Cry1Ac toxin in the Cry1Ac-susceptible P. xylostella strain. Furthermore, silencing of PxMAP4K4 expression increased the expression of both POUM1 and PxABCG1 genes in the Cry1Ac-resistant P. xylostella strain. These results indicate that the POUM1 induces PxABCG1 expression, while the activated MAPK cascade represses PxABCG1 expression thus reducing Cry1Ac susceptibility in P. xylostella. This result deepens our understanding of the transcriptional regulatory mechanism of midgut Cry receptor genes and the molecular basis of the evolution of Bt resistance in insects.
Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Animales , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/farmacología , Endotoxinas/metabolismo , Endotoxinas/farmacología , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacología , Proteínas de Insectos/genética , Resistencia a los Insecticidas/genética , Larva/genética , Larva/metabolismo , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismo , Factores de Transcripción/genéticaRESUMEN
Tomato is an economically crucial vegetable/fruit crop globally. Tomato is rich in nutrition and plays an essential role in a healthy human diet. Phenylpropanoid, a critical compound in tomatoes, reduces common degenerative and chronic diseases risk caused by oxidative stress. As an MYB transcription factor, ATMYB12 can increase phenylpropanoid content by activating phenylpropanoid synthesis related genes, such as PAL, C4H, 4CL, CHS. However, the heterologous expression of AtMYB12 in tomatoes can be altered through transgenic technologies, such as unstable expression vectors and promoters with different efficiency. In the current study, the efficiency of other fruit-specific promoters, namely E8S, 2A12, E4, and PG, were compared and screened, and we determined that the expression efficiency of AtMYB12 was driven by the E8S promoter was the highest. As a result, the expression of phenylpropanoid synthesis related genes was regulated by AtMYB12, and the phenylpropanoid accumulation in transgenic tomato fruits increased 16 times. Additionally, the total antioxidant capacity of fruits was measured through Trolox equivalent antioxidant capacity (TEAC) assay, which was increased by 2.4 times in E8S transgenic lines. TEAC was positively correlated with phenylpropanoid content. Since phenylpropanoid plays a crucial role in the human diet, expressing AtMYB12 with stable and effective fruit-specific promoter E8S could improve tomato's phenylpropanoid and nutrition content and quality. Our results can provide genetic resources for the subsequent improvement of tomato varieties and quality, which is significant for human health.
Asunto(s)
Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Regiones Promotoras Genéticas , Propanoles/metabolismo , Solanum lycopersicum/fisiología , Factores de Transcripción/genética , Vías Biosintéticas , Cromatografía Líquida de Alta Presión , Especificidad de Órganos/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
BACKGROUND: Anastomosis group 1 IA (AG1-IA) of Rhizoctonia solani is the major agent of banded leaf and sheath blight (BLSB) disease that causes severe yield loss in many worldwide crops. MicroRNAs (miRNAs) are ~ 22 nt non-coding RNAs that negatively regulate gene expression levels by mRNA degradation or translation inhibition. A better understanding of miRNA function during AG1-IA infection can expedite to elucidate the molecular mechanisms of fungi-host interactions. RESULTS: In this study, we sequenced three small RNA libraries obtained from the mycelium of AG1-IA isolate, non-infected maize sheath and mixed maize sheath 3 days after inoculation. In total, 137 conserved and 34 novel microRNA-like small RNAs (milRNAs) were identified from the pathogen. Among these, one novel and 17 conserved milRNAs were identified as potential virulence-associated (VA) milRNAs. Subsequently, the prediction of target genes for these milRNAs was performed in both AG1-IA and maize, while functional annotation of these targets suggested a link to pathogenesis-related biological processes. Further, expression patterns of these virulence-associated milRNAs demonstrated that theyparticipate in the virulence of AG1-IA. Finally, regulation of one maize targeting gene, GRMZM2G412674 for Rhi-milRNA-9829-5p, was validated by dual-luciferase assay and identified to play a positive role in BLSB resistance in two maize mutants. These results suggest the global differentially expressed milRNAs of R. solani AG1-IA that participate in the regulation of target genes in both AG1-IA and maize to reinforce its pathogenicity. CONCLUSIONS: Our data have provided a comprehensive overview of the VA-milRNAs of R. solani and identified that they are probably the virulence factors by directly interfered in host targeting genes. These results offer new insights on the molecular mechanisms of R.solani-maize interactions during the process of infection.
Asunto(s)
MicroARNs/fisiología , Enfermedades de las Plantas/microbiología , Rhizoctonia/patogenicidad , Zea mays/microbiología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedades de las Plantas/genética , ARN Bacteriano/fisiología , Rhizoctonia/genética , Virulencia/genética , Zea mays/genéticaRESUMEN
Deciphering the molecular mechanisms underlying insect resistance to Cry toxins produced by Bacillus thuringiensis (Bt) is pivotal for the sustainable utilization of Bt biopesticides and transgenic Bt crops. Previously, we identified that mitogen-activated protein kinase (MAPK)-mediated reduced expression of the PxABCB1 gene is associated with Bt Cry1Ac resistance in the diamondback moth, Plutella xylostella (L.). However, the underlying transcriptional regulation mechanism remains enigmatic. Here, the PxABCB1 promoter in Cry1Ac-susceptible and Cry1Ac-resistant P. xylostella strains was cloned and analyzed and found to contain a putative Jun binding site (JBS). A dual-luciferase reporter assay and yeast one-hybrid assay demonstrated that the transcription factor PxJun repressed PxABCB1 expression by interacting with this JBS. The expression levels of PxJun were increased in the midguts of all resistant strains compared to the susceptible strain. Silencing of PxJun expression significantly elevated PxABCB1 expression and Cry1Ac susceptibility in the resistant NIL-R strain, and silencing of PxMAP4K4 expression decreased PxJun expression and also increased PxABCB1 expression. These results indicate that MAPK-activated PxJun suppresses PxABCB1 expression to confer Cry1Ac resistance in P. xylostella, deepening our understanding of the transcriptional regulation of midgut Cry receptor genes and the molecular basis of insect resistance to Bt Cry toxins. IMPORTANCE The transcriptional regulation mechanisms underlying reduced expression of Bt toxin receptor genes in Bt-resistant insects remain elusive. This study unveils that a transcription factor PxJun activated by the MAPK signaling pathway represses PxABCB1 expression and confers Cry1Ac resistance in P. xylostella. Our results provide new insights into the transcriptional regulation mechanisms of midgut Cry receptor genes and deepen our understanding of the molecular basis of insect resistance to Bt Cry toxins. To our knowledge, this study identified the first transcription factor that can be involved in the transcriptional regulation mechanisms of midgut Cry receptor genes in Bt-resistant insects.
Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Toxinas de Bacillus thuringiensis/farmacología , Endotoxinas/farmacología , Proteínas Hemolisinas/farmacología , Proteínas de Insectos/genética , Resistencia a los Insecticidas/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Mariposas Nocturnas , Proteínas Proto-Oncogénicas c-jun/genética , Animales , Larva/genética , Larva/metabolismo , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismoRESUMEN
BACKGROUND The aim of this study was to analyze the value of ocular endoscopy in detecting and extracting intraocular cilia in patients with ocular trauma. MATERIAL AND METHODS We retrospectively analyzed data on identification and extraction of 46 intraocular cilia in 16 eyes with open-globe injury during endoscope-assisted vitrectomy. RESULTS A total of the 16 patients with open-globe injury were operated on from September 2002 to June 2019. The cornea in 14 eyes was cloudy. Two eyes had endophthalmitis and 13 eyes had retinal detachment. A total of 46 cilia were extracted through direct observation under the ocular endoscope during vitrectomy 1 to 68 weeks after injury. The number of cilia per eye varied from 1 to 10. Most of the cilia were located in or near the wound. Postoperative IOP was normal in 14 patients. The follow-up after surgery showed hypotony in only 2 eyes (7.2 and 5.8 mmHg, respectively). Compared with preoperative intraocular pressure, there was a statistically significant difference. The postoperative visual acuity improved in 12 eyes and remained unchanged in 3 eyes. The vision after surgery was significantly improved compared with that before surgery (P=0.006). The intraocular pressure increased significantly after operation (P<0.001). And no glaucoma or retinal detachment or endophthalmitis was found. No eyes needed additional vitreous surgery. CONCLUSIONS Ocular endoscopy allows surgeons to detect intraocular cilia that were no undetected by CT or B-ultrasound preoperatively in time and to extract them effectively. It improves performance of vitrectomy in the presence of a cloudy cornea and also prevents exogenous endophthalmitis. The vision of patients with ocular trauma was improved.
Asunto(s)
Endoscopía , Cuerpos Extraños en el Ojo/cirugía , Lesiones Oculares Penetrantes/cirugía , Adolescente , Adulto , Niño , Preescolar , Cuerpos Extraños en el Ojo/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
PURPOSE: To analyze the characteristics, related risk factors, and prognosis of suprachoroidal hemorrhage (SCH) associated with pars plana vitrectomy (PPV). METHODS: Cases of SCH associated with PPV excluding trauma were retrospectively analyzed in Beijing Tongren Hospital between January 2010 and June 2020. The data collected included general data, myopia status, axial length, state of the crystalline lens, SCH onset time, range, treatment method, visual prognosis, and methods of operation and anesthesia. Patients were divided into those with SCH related to the first PPV (Group 1), and SCH related to second intraocular surgery in the vitrectomized eye (Group 2). Patients were also classified by the SCH onset time into either the expulsive suprachoroidal hemorrhage group (ESCH) and the delayed suprachoroidal hemorrhage group (DSCH). The general data, related risk factors, and the visual prognosis of SCH in the different groups were analyzed. RESULTS: SCH associated with PPV was studied in 28 cases with an incidence of 0.06 %; 16 males and 12 females. The mean age of the patients was (53.51 ± 10.21) years old, the mean follow-up time was (24.94 ± 14.60) days, and the mean axial length was (28.21 ± 3.14) mm. Of these cases, 21 were classified as high myopia, 25 as aphakia/ pseudophakic, and 7 as focal hemorrhage. Silicone oil removal occurred in 12 cases (43 %). Patients in Group 2 were younger than Group 1 (P = 0.005). In terms of treatment and prognosis, 5 eyes were simply closely observed, 4 were given single suprachoroidal drainage, 15 were given suprachoroidal drainage combined with silicone tamponade, 2 underwent anterior chamber puncture, and 2 gave up treatment. A follow-up vision: NLP ~ 20/30; among them, 2 eyes with NLP (7.14 %), 6 of ≥ 20/200 (21.43 %). The final outcomes presented a significantly positive correlation with baseline vision but no significant correlation with age or axial length. CONCLUSIONS: SCH has a higher incidence rate after a second intraocular surgery in a vitrectomized eye which is associated with the lack of vitreous support and easier fluctuation of intraocular pressure. SCH associated with PPV is more localized and has a relatively good prognosis; high myopia and aphakic/ pseudophakic eyes are risk factors. Active treatment can effectively improve visual prognosis. TRIAL REGISTRATION: Retrospective case series study, not applicable.
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Hemorragia de la Coroides , Desprendimiento de Retina , Adulto , Hemorragia de la Coroides/diagnóstico , Hemorragia de la Coroides/epidemiología , Hemorragia de la Coroides/etiología , Femenino , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Desprendimiento de Retina/cirugía , Estudios Retrospectivos , Agudeza Visual , VitrectomíaRESUMEN
The parasitoid of whiteflies Encarsia formosa has been widely applied to reduce whitefly-mediated damage on vegetables and ornamental plants grown in greenhouses. Although its chemosensory behavior has been described, the mechanism by which E. formosa recognizes chemical volatiles at the molecular level remains unknown. In this study, we obtained 66,632 unigenes from antennae transcriptomic architecture of E. formosa, of which 19,473 (29.2%) were functionally annotated. All that matters is that we manually identified 39 odorant-binding proteins (OBPs) from above dataset, and further investigated the tissue and stage-specific expression profiles of all identified OBP genes by real-time quantitative PCR. Among these OBP genes, 32 were enriched in antennae, and 2 in body. In addition, 4 OBPs were highly expressed in pupae, and 32 in 6-hour-age adults after eclosion. In addition to identifying OBP genes from E. formosa, this study provides a molecular basis for further functional studies of OBPs and the interactions of hosts and parasitic wasps.