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1.
Front Neurosci ; 18: 1305284, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495107

RESUMO

Previous studies have successfully applied a lightweight recurrent neural network (RNN) called Echo State Network (ESN) for EEG-based emotion recognition. These studies use intrinsic plasticity (IP) and synaptic plasticity (SP) to tune the hidden reservoir layer of ESN, yet they require extra training procedures and are often computationally complex. Recent neuroscientific research reveals that the brain is modular, consisting of internally dense and externally sparse subnetworks. Furthermore, it has been proved that this modular topology facilitates information processing efficiency in both biological and artificial neural networks (ANNs). Motivated by these findings, we propose Modular Echo State Network (M-ESN), where the hidden layer of ESN is directly initialized to a more efficient modular structure. In this paper, we first describe our novel implementation method, which enables us to find the optimal module numbers, local and global connectivity. Then, the M-ESN is benchmarked on the DEAP dataset. Lastly, we explain why network modularity improves model performance. We demonstrate that modular organization leads to a more diverse distribution of node degrees, which increases network heterogeneity and subsequently improves classification accuracy. On the emotion arousal, valence, and stress/calm classification tasks, our M-ESN outperforms regular ESN by 5.44, 5.90, and 5.42%, respectively, while this difference when comparing with adaptation rules tuned ESNs are 0.77, 5.49, and 0.95%. Notably, our results are obtained using M-ESN with a much smaller reservoir size and simpler training process.

2.
Sci Total Environ ; 919: 170920, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38354797

RESUMO

Variation in biomass elemental composition of grassland plants may have important implications for ecosystem functioning in response to global change. However, relevant studies have mostly focused on variation of nitrogen (N) and phosphorus (P) concentrations in plant leaves, while few studies have evaluated other elements and plant organs of grassland species. Here, we examined the effects of N addition on multi-element concentrations, and analyzed their patterns across different organs (leaf, stem, root and seed) of five plant species in a steppe community of the Inner Mongolian grassland. Our results showed that seeds exhibited the most stable elemental composition with N addition, and that manganese (Mn) and iron (Fe) concentrations were substantially more variable than macro-elements in response to N addition. In particular, we identified a set of significant negative relationships between elemental concentrations and their corresponding CVs (coefficients of variation) for all plant organs as a whole and for each individual organ. We further found that changes in soil pH and the availability of soil nutrients contributed mostly to variation in the biomass elemental composition of major plants in this community. These findings are important for accurately assessing the effects of N deposition on the biochemical cycling of nutrient elements in grassland ecosystems, and provide critical clues for developing effective approaches to adaptively managing grassland resources as well as mitigating the impact of global change on the dryland ecosystems in the Mongolia Plateau.


Assuntos
Ecossistema , Nitrogênio , Nitrogênio/análise , Pradaria , Biomassa , Plantas , Sementes/química , Solo/química , China
3.
Front Oncol ; 13: 1128636, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37182167

RESUMO

Objective: To retrospectively analyze the reasons for misdiagnosis of haematolymphoid neoplasms and provide experience for improving the diagnostic level in China. Methods: A retrospective analysis was performed on 2291 cases of haematolymphoid diseases evaluated by the Department of Pathology of our hospital from 1 July 2019 to 30 June 2021. All 2291 cases were reviewed by two hematopathologist experts and classified according to the 2017 revised WHO classification criteria, supplemented immunohistochemistry (IHC), molecular biology and genetic information as needed. The diagnostic discordance between primary and expert review was evaluated. The possible causes of the diagnostic discrepancies were analyzed for each step involved in the procedure of diagnosis. Results: In total, 912 cases did not conform to the expert diagnoses among all the 2291 cases, with a total misdiagnosis rate of 39.8%. Among them, misdiagnosis between benign and malignant lesions accounted for 24.3% (222/912), misdiagnosis between haematolymphoid neoplasms and non-haematolymphoid neoplasms accounted for 3.3% (30/912), misdiagnosis among lineages accounted for 9.3% (85/912), misclassification in lymphoma subtypes accounted for 60.8% (554/912), and other misdiagnoses among benign lesions accounted for 2.3% (21/912) of cases, among which misclassification of lymphoma subtypes was the most common. Conclusion: The accurate diagnosis of haematolymphoid neoplasms is challenging, involving various types of misdiagnosis and complicated causes, however, it is important for precise treatment. Through this analysis, we aimed to highlight the importance of accurate diagnosis, avoid diagnostic pitfalls and to improve the diagnostic level in our country.

4.
BMC Neurol ; 23(1): 142, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37016325

RESUMO

BACKGROUND: Migraine is a complex disorder characterized by debilitating headaches. Despite its prevalence, its pathophysiology remains unknown, with subsequent gaps in diagnosis and treatment. We combined machine learning with connectivity analysis and applied a whole-brain network approach to identify potential targets for migraine diagnosis and treatment. METHODS: Baseline anatomical T1 magnetic resonance imaging (MRI), resting-state functional MRI(rfMRI), and diffusion weighted scans were obtained from 31 patients with migraine, and 17 controls. A recently developed machine learning technique, Hollow Tree Super (HoTS) was used to classify subjects into diagnostic groups based on functional connectivity (FC) and derive networks and parcels contributing to the model. PageRank centrality analysis was also performed on the structural connectome to identify changes in hubness. RESULTS: Our model attained an area under the receiver operating characteristic curve (AUC-ROC) of 0.68, which rose to 0.86 following hyperparameter tuning. FC of the language network was most predictive of the model's classification, though patients with migraine also demonstrated differences in the accessory language, visual and medial temporal regions. Several analogous regions in the right hemisphere demonstrated changes in PageRank centrality, suggesting possible compensation. CONCLUSIONS: Although our small sample size demands caution, our preliminary findings demonstrate the utility of our method in providing a network-based perspective to diagnosis and treatment of migraine.


Assuntos
Conectoma , Transtornos de Enxaqueca , Humanos , Transtornos de Enxaqueca/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Conectoma/métodos , Imageamento por Ressonância Magnética/métodos , Idioma
5.
Microb Ecol ; 85(1): 221-231, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35043220

RESUMO

Soil microorganisms play key roles in terrestrial biogeochemical cycles and ecosystem functions. However, few studies address how long-term nitrogen (N) addition gradients impact soil bacterial and fungal diversity and community composition simultaneously. Here, we investigated soil bacterial and fungal diversity and community composition based on a long-term (17 years) N addition gradient experiment (six levels: 0, 2, 4, 8, 16, 32 gN m-2 year-1) in temperate grassland, using the high-throughput Illumina MiSeq sequencing. Results showed that both soil bacterial and fungal alpha diversity responded nonlinearly to the N input gradient and reduced drastically when the N addition rate reached 32 g N m-2 year-1. The relative abundance of soil bacterial phyla Proteobacteria increased and Acidobacteria decreased significantly with increasing N level. In addition, the relative abundance of bacterial functional groups associated with aerobic ammonia oxidation, aerobic nitrite oxidation, nitrification, respiration of sulfate and sulfur compounds, and chitinolysis significantly decreased under the highest N addition treatment. For soil fungi, the relative abundance of Ascomycota increased linearly along the N enrichment gradient. These results suggest that changes in soil microbial community composition under elevated N do not always support the copiotrophic-oligotrophic hypothesis, and some certain functional bacteria would not simply be controlled by soil nutrients. Further analysis illustrated that reduced soil pH under N addition was the main factor driving variations in soil microbial diversity and community structure in this grassland. Our findings highlight the consistently nonlinear responses of soil bacterial and fungal diversity to increasing N input and the significant effects of soil acidification on soil microbial communities, which can be helpful for the prediction of underground ecosystem processes in light of future rising N deposition.


Assuntos
Microbiota , Solo , Solo/química , Pradaria , Microbiologia do Solo , Bactérias/genética , Fungos/genética , Concentração de Íons de Hidrogênio
6.
Elife ; 112022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36579891

RESUMO

HOTAIR is a 2.2-kb long noncoding RNA (lncRNA) whose dysregulation has been linked to oncogenesis, defects in pattern formation during early development, and irregularities during the process of epithelial-to-mesenchymal transition (EMT). However, the oncogenic transformation determined by HOTAIR in vivo and its impact on chromatin dynamics are incompletely understood. Here, we generate a transgenic mouse model with doxycycline-inducible expression of human HOTAIR in the context of the MMTV-PyMT breast cancer-prone background to systematically interrogate the cellular mechanisms by which human HOTAIR lncRNA acts to promote breast cancer progression. We show that sustained high levels of HOTAIR over time increased breast metastatic capacity and invasiveness in breast cancer cells, promoting migration and subsequent metastasis to the lung. Subsequent withdrawal of HOTAIR overexpression reverted the metastatic phenotype, indicating oncogenic lncRNA addiction. Furthermore, HOTAIR overexpression altered both the cellular transcriptome and chromatin accessibility landscape of multiple metastasis-associated genes and promoted EMT. These alterations are abrogated within several cell cycles after HOTAIR expression is reverted to basal levels, indicating an erasable lncRNA-associated epigenetic memory. These results suggest that a continual role for HOTAIR in programming a metastatic gene regulatory program. Targeting HOTAIR lncRNA may potentially serve as a therapeutic strategy to ameliorate breast cancer progression.


Assuntos
Neoplasias da Mama , RNA Longo não Codificante , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Cromatina , Regulação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Camundongos Transgênicos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Pulmonares/secundário
7.
J Integr Neurosci ; 21(6): 150, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36424741

RESUMO

BACKGROUND: Current data indicates the incidence of neuropathic pain after surgical nerve injury is as high as 50%, thus representing a major problem for patients and for the medical system. Triptolide, a traditional Chinese herb, has anti-inflammatory effects on various neurodegenerative and neuroinflammatory diseases. This agent also reduces peripheral nerve injury-induced neuropathic pain, although the mechanism underlying this effect is still unknown. MATERIALS AND METHODS: The effects of triptolide on spinal nerve ligation (SNL) injury-induced neuropathic pain was studied in an animal model using behavioral, morphological and molecular biological methods. RESULTS: Repeated administration of intrathecal triptolide was found to alleviate SNL- or Poly(I:C) (toll-like receptor 3 agonist) injection-induced mechanical allodynia without any motor impairment. The mechanism by which triptolide reduces SNL- and Poly(I:C) injection-induced microglial activation appears to be via the inhibition of OX42 expression, which is a microglial-specific marker. Intrathecal triptolide also suppressed SNL- and Poly(I:C) injection-induced expression of spinal TRIF. TRIF transmits signals from activated TLR3 and is the downstream adaptor of TLR3 in microglia. In addition, intrathecal triptolide inhibited the expression of spinal pro-inflammatory IL-1 ß following SNL or Poly(I:C) injection. CONCLUSIONS: Intrathecal triptolide can suppress the TLR3/TRIF/IL-1 ß pathway in spinal microglia following SNL. This could be the underlying mechanism by which triptolide alleviate neuropathic pain induced by peripheral nerve injury.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Ratos , Animais , Microglia , Receptor 3 Toll-Like/metabolismo , Interleucina-1beta/metabolismo , Ratos Sprague-Dawley , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/farmacologia
8.
Biosci Rep ; 42(11)2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36305246

RESUMO

Hypertension affects 30% of adults and is the leading risk factor for cardiovascular disease. Kidney sodium reabsorption plays a vital role in the initial stage and development of essential hypertension. It has been extensively reported that the variants of kidney ion handling genes are associated to blood pressure, and clinical features of hypertension. However, the underlying mechanisms by which these variants alter protein function are rarely summarized. In addition, the variation of one single gene is often limited to induce a significant effect on blood pressure. In the past few decades, the influence by genes × genes (G × G) and/or genotype × environment (G × E) interactions on a given trait, for example, blood pressure, have been widely considered, especially in studies on polygenic genetic traits. In the present review, we discuss the progress in genetics studies on kidney ion handling genes, encoding Na+ channels (Na+-Cl- cotransporter [NCC], Na-K-2Cl cotransporter [NKCC2], epithelial Na+ channels [ENaCs]), K+ channel (renal outer medullary potassium channel [ROMK]), and Cl- channels (Pendrin, chloride voltage-gated channel Kb [CLC-Kb]), respectively, and their upstream kinases, WNKs and SGK1. We seek to clarify how these genes are involved in kidney sodium absorption and influence blood pressure, especially emphasizing the underlying mechanisms by which genetic variants alter protein functions and interaction in blood pressure regulation. The present review aims to enhance our understanding of the important role of kidney ion handling genes/channels in blood pressure control.


Assuntos
Hipertensão , Rim , Adulto , Humanos , Pressão Sanguínea/genética , Rim/metabolismo , Sódio , Simportadores de Cloreto de Sódio-Potássio , Membro 3 da Família 12 de Carreador de Soluto
9.
Genes Dis ; 9(6): 1478-1492, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36157489

RESUMO

Sexual dimorphism has been reported in various human diseases including autoimmune diseases, neurological diseases, pulmonary arterial hypertension, and some types of cancers, although the underlying mechanisms remain poorly understood. The long noncoding RNA (lncRNA) X-inactive specific transcript (XIST) is involved in X chromosome inactivation (XCI) in female placental mammals, a process that ensures the balanced expression dosage of X-linked genes between sexes. XIST is abnormally expressed in many sex-biased diseases. In addition, escape from XIST-mediated XCI and skewed XCI also contribute to sex-biased diseases. Therefore, its expression or modification can be regarded as a biomarker for the diagnosis and prognosis of many sex-biased diseases. Genetic manipulation of XIST expression can inhibit the progression of some of these diseases in animal models, and therefore XIST has been proposed as a potential therapeutic target. In this manuscript, we summarize the current knowledge about the mechanisms for XIST-mediated XCI and the roles of XIST in sex-biased diseases, and discuss potential therapeutic strategies targeting XIST.

10.
Front Plant Sci ; 13: 864986, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463412

RESUMO

Leaf senescence is a developmentally programmed cell death process that is influenced by a variety of endogenous signals and environmental factors. Here, we report that MPK3 and MPK6, two Arabidopsis mitogen-activated protein kinases (MAPKs or MPKs), and their two upstream MAPK kinases (MAPKKs or MKKs), MKK4 and MKK5, are key regulators of leaf senescence. Weak induction of constitutively active MAPKKs driven by steroid-inducible promoter, which activates endogenous MPK3 and MPK6, induces leaf senescence. This gain-of-function phenotype requires functional endogenous MPK3 and MPK6. Furthermore, loss of function of both MKK4 and MKK5 delays leaf senescence. Expression profiling leads to the identification of matrix metalloproteinases (MMPs), a family of zinc- and calcium-dependent endopeptidases, as the downstream target genes of MPK3/MPK6 cascade. MPK3/MPK6 activation-triggered leaf senescence is associated with rapid and strong induction of At3-MMP and At2-MMP. Expression of Arabidopsis MMP genes is strongly induced during leaf senescence, qualifying them as senescence-associated genes (SAGs). In addition, either constitutive or inducible overexpression of At3-MMP is sufficient to trigger leaf senescence. Based on these findings, we conclude that MPK3/MPK6 MAPK cascade and MMP target genes further downstream are involved in regulating leaf senescence in Arabidopsis.

11.
Biomed Pharmacother ; 148: 112703, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35149384

RESUMO

MiR-16-5p, a member of the miR-16 family, has been reported to be abnormal expression in tumor tissues and blood of tumor patients, and also downregulated in most cancer cell lines. Aberrant expression of miR-16-5p promotes tumor cell proliferation, invasion, metastasis, angiogenesis, and can also affect the treatment sensitivity, such as radiotherapy and chemotherapy. Generally, miR-16-5p plays an anti-tumor role and these diverse functions of miR-16-5p in tumors collectively indicate that miR-16-5p may become an attractive target for novel anticancer therapies and a powerful diagnostic and prognostic biomarker for early tumor detection and population risk screening. Herein we review the role and utilization of miR-16-5p in malignant tumor in detail.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo
12.
Front Cell Dev Biol ; 9: 730014, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34760887

RESUMO

Genomic imprinting is a term used for an intergenerational epigenetic inheritance and involves a subset of genes expressed in a parent-of-origin-dependent way. Imprinted genes are expressed preferentially from either the paternally or maternally inherited allele. Long non-coding RNAs play essential roles in regulating this allele-specific expression. In several well-studied imprinting clusters, long non-coding RNAs have been found to be essential in regulating temporal- and spatial-specific establishment and maintenance of imprinting patterns. Furthermore, recent insights into the epigenetic pathological mechanisms underlying human genomic imprinting disorders suggest that allele-specific expressed imprinted long non-coding RNAs serve as an upstream regulator of the expression of other protein-coding or non-coding imprinted genes in the same cluster. Aberrantly expressed long non-coding RNAs result in bi-allelic expression or silencing of neighboring imprinted genes. Here, we review the emerging roles of long non-coding RNAs in regulating the expression of imprinted genes, especially in human imprinting disorders, and discuss three strategies targeting the central long non-coding RNA UBE3A-ATS for the purpose of developing therapies for the imprinting disorders Prader-Willi syndrome and Angelman syndrome. In summary, a better understanding of long non-coding RNA-related mechanisms is key to the development of potential therapeutic targets for human imprinting disorders.

13.
J Genet Genomics ; 48(8): 695-705, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34315684

RESUMO

Coordination between the sporophytic tissue and the gametic pollen within anthers is tightly controlled to achieve the optimal pollen fitness. Glucose-6-phosphate/phosphate translocator (GPT) transports glucose-6-phosphate, a key precursor of starch and/or fatty acid biosynthesis, into plastids. Here, we report the functional characterization of OsGPT1 in the rice anther development and pollen fertility. Pollen grains from homozygous osgpt1 mutant plants fail to accumulate starch granules, resulting in pollen sterility. Genetic analyses reveal a sporophytic effect for this mutation. OsGPT1 is highly expressed in the tapetal layer of rice anther. Degeneration of the tapetum, an important process to provide cellular contents to support pollen development, is impeded in osgpt1 plants. In addition, defective intine and exine are observed in the pollen from osgpt1 plants. Expression levels of multiple genes that are important to tapetum degeneration or pollen wall formation are significantly decreased in osgpt1 anthers. Previously, we reported that AtGPT1 plays a gametic function in the accumulation of lipid bodies in Arabidopsis pollen. This report highlights a sporophytic role of OsGPT1 in the tapetum degeneration and pollen development. The divergent functions of OsGPT1 and AtGPT1 in pollen development might be a result of their independent evolution after monocots and dicots diverged.


Assuntos
Glucose-6-Fosfato
14.
Artigo em Inglês | MEDLINE | ID: mdl-34211565

RESUMO

BACKGROUND: Renal interstitial fibrosis is a pathological manifestation of progression of chronic kidney disease induced by various factors. Shen Shuai II Recipe (SSR) has been used in clinical practice for more than 20 years, and clinical studies have confirmed that SSR significantly improves the renal function of patients with chronic kidney disease. However, the specific mechanisms underlying its efficacy require further research. This study aims to explore the influencing factors of renal interstitial fibrosis in the context of hypoxia via the IL-1ß/c-Myc pathway and the potential molecular mechanisms of SSR intervention in vivo and in vitro. METHODS: A rat model of chronic renal failure was developed by performing 5/6 (ablation/infarction, A/I) surgery on randomly selected, male Sprague Dawley rats. Thirty-six successfully modeled rats were randomly divided into three groups: 5/6 (A/I), 5/6 (A/I) + SSR, and 5/6 (A/I) + losartan. Another 12 rats were used as the sham group. After 8 weeks of the corresponding intervention, renal function, liver function, and protein expression of renal-fibrosis-related factors, HIF-1α, IL-1ß, and c-Myc, were detected. In vitro analysis was performed using hypoxia-induced rat renal tubular epithelial cells (NRK-52E) and IL-1ß-stimulated rat renal interstitial fibroblasts (NRK-49F). IL-1ß concentration in the culture medium and IL-1ß protein expression in hypoxic NRK-52E treated with different concentrations of SSR were investigated. Furthermore, we also studied the changes in protein expression of c-Myc and fibrosis-related factors after c-Myc gene silencing in IL-1ß-stimulated NRK-49F treated with SSR. RESULTS: Shen Shuai II Recipe significantly reduced RIF and downregulated the expression of HIF-1α, c-Myc, and IL-1ß proteins in 5/6 (A/I) rats with chronic renal failure. It also inhibited IL-1ß secretion from NRK-52E induced by hypoxia, which in turn inhibited fibroblast activation mediated by the IL-1ß/c-Myc pathway, and finally reduced the overproduction of the extracellular matrix. CONCLUSION: The renoprotective effects of SSR in rats with chronic renal failure may be related to its inhibition of hypoxia via the IL-1ß/c-Myc pathway. Thus, SSR is a potentially effective drug for delaying the progression of renal interstitial fibrosis.

15.
Ecol Evol ; 11(3): 1175-1186, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33598122

RESUMO

One of the key aims of global change studies is to predict more accurately how plant community composition responds to future environmental changes. Although interspecific relationship is one of the most important forces structuring plant communities, it remains a challenge to integrate long-term consequences at the plant community level. As an increasing number of studies have shown that maternal environment affects offspring phenotypic plasticity as a response to global environment change through transgenerational effects, we speculated that the transgenerational effect would influence offspring competitive relationships. We conducted a 10-year field experiment and a greenhouse experiment in a temperate grassland in an Inner Mongolian grassland to examine the effects of maternal and immediate nitrogen addition (N) and increased precipitation (Pr) on offspring growth and the interspecific relationship between the two dominant species, Stipa krylovii and Artemisia frigida. According to our results, Stipa kryloii suppressed A. frigida growth and population development when they grew in mixture, although immediate N and Pr stimulated S. kryloii and A. frigida growth simultaneously. Maternal N and Pr declined S. krylovii dominance and decreased A. frigida competitive suppression to some extent. The transgenerational effect should further facilitate the coexistence of the two species under scenarios of increased nitrogen input and precipitation. If we predicted these species' interspecific relationships based only on immediate environmental effects, we would overestimate S. krylovii's competitive advantage and population development, and underestimate competitive outcome and population development of A. frigida. In conclusion, our results demonstrated that the transgenerational effect of maternal environment on offspring interspecific competition must be considered when evaluating population dynamics and community composition under the global change scenario.

16.
J Integr Plant Biol ; 62(11): 1780-1796, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32449805

RESUMO

Secondary plant metabolites, represented by indole glucosinolates (IGS) and camalexin, play important roles in Arabidopsis immunity. Previously, we demonstrated the importance of MPK3 and MPK6, two closely related MAPKs, in regulating Botrytis cinerea (Bc)-induced IGS and camalexin biosynthesis. Here we report that CPK5 and CPK6, two redundant calcium-dependent protein kinases (CPKs), are also involved in regulating the biosynthesis of these secondary metabolites. The loss-of-function of both CPK5 and CPK6 compromises plant resistance to Bc. Expression profiling of CPK5-VK transgenic plants, in which a truncated constitutively active CPK5 is driven by a steroid-inducible promoter, revealed that biosynthetic genes of both IGS and camalexin pathways are coordinately upregulated after the induction of CPK5-VK, leading to high-level accumulation of camalexin and 4-methoxyindole-3-yl-methylglucosinolate (4MI3G). Induction of camalexin and 4MI3G, as well as the genes in their biosynthesis pathways, is greatly compromised in cpk5 cpk6 mutant in response to Bc. In a conditional cpk5 cpk6 mpk3 mpk6 quadruple mutant, Bc resistance and induction of IGS and camalexin are further reduced in comparison to either cpk5 cpk6 or conditional mpk3 mpk6 double mutant, suggesting that both CPK5/CPK6 and MPK3/MPK6 signaling pathways contribute to promote the biosynthesis of 4MI3G and camalexin in defense against Bc.


Assuntos
Glucosinolatos/metabolismo , Indóis/metabolismo , Tiazóis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Botrytis/patogenicidade , Regulação da Expressão Gênica de Plantas/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Imunidade Vegetal/fisiologia , Transdução de Sinais/fisiologia
17.
J Integr Plant Biol ; 62(11): 1797-1812, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32458527

RESUMO

Gamma-aminobutyric acid (GABA) is an important metabolite which functions in plant growth, development, and stress responses. However, its role in plant defense and how it is regulated are largely unknown. Here, we report a detailed analysis of GABA induction during the resistance response to Pseudomonas syringae in Arabidopsis thaliana. While searching for the mechanism underlying the pathogen-responsive mitogen-activated protein kinase (MPK)3/MPK6 signaling cascade in plant immunity, we found that activation of MPK3/MPK6 greatly induced GABA biosynthesis, which is dependent on the glutamate decarboxylase genes GAD1 and GAD4. Inoculation with Pseudomonas syringae pv tomato DC3000 (Pst) and Pst-avrRpt2 expressing the avrRpt2 effector gene induced GAD1 and GAD4 gene expression and increased the levels of GABA. Genetic evidence revealed that GAD1, GAD2, and GAD4 play important roles in both GABA biosynthesis and plant resistance in response to Pst-avrRpt2 infection. The gad1/2/4 triple and gad1/2/4/5 quadruple mutants, in which the GABA levels were extremely low, were more susceptible to both Pst and Pst-avrRpt2. Functional loss of MPK3/MPK6, or their upstream MKK4/MKK5, or their downstream substrate WRKY33 suppressed the induction of GAD1 and GAD4 expression after Pst-avrRpt2 treatment. Our findings shed light on both the regulation and role of GABA in the plant immunity to a bacterial pathogen.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Pseudomonas syringae/patogenicidade , Ácido gama-Aminobutírico/metabolismo , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Imunidade Vegetal/fisiologia , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/microbiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
18.
Biomed Pharmacother ; 118: 109316, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31387002

RESUMO

Apoptosis is closely interconnected with the severity of renal injury. Magnesium lithospermate B (MLB) extracted from Salviae miltiorrhizae radix showed a wide range of renoprotective effects. However, the underlying mechanisms under beneficial effects have not been elucidated. This study was conducted to investigate whether MLB could mediate renal protection and attenuate apoptosis by mitochondrial pathway. In the present study, the rat model of chronic renal failure (CRF) was established by the 5/6 renal ablation/infarction (A/I) operation. 28 days after the surgery, 30 rats were randomly divided into three groups: sham group, 5/6 (A/I) group and 5/6 (A/I) + MLB group. After 56 days of treatment, we detected the severity of kidney injury, the degree of mitochondrial bax oligomerization and cytochrome c release along with the expression of P53 protein. Our results showed that MLB markedly attenuated kidney injury and apoptosis in 5/6 (A/I) model rats with CRF. MLB effectively inhibited mitochondrial bax accumulation and release of cytochrome c into the cytosol and down-regulated the levels of p53 phosphorylation and acetylation. These data showed that MLB could contribute to renal protection by inhibiting mitochondrial pathway of apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Rim/patologia , Mitocôndrias/patologia , Animais , Citocromos c/metabolismo , Citosol/metabolismo , Modelos Animais de Doenças , Rim/efeitos dos fármacos , Masculino , Mitocôndrias/efeitos dos fármacos , Multimerização Proteica , Ratos Sprague-Dawley , Insuficiência Renal Crônica/patologia , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
19.
BMC Complement Altern Med ; 19(1): 107, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118021

RESUMO

BACKGROUND: Excessive activation of NLRP3 inflammasome and down-regulation of Sirt1/Smad3 deacetylation pathway play a significant role in the evolution of renal fibrosis. In China, it has been well known that Chinese herbal medicine is markedly effective in treating chronic kidney disease (CKD). Shen Shuai IIRecipe (SSR) has been used clinically for more than 20 years and has been confirmed to be effective in improvements of renal function and fibrosis. However, the specific mechanisms under the efficacy require further research. The purpose of this study was to evaluate whether SSR could alleviate renal injury and fibrosis by regulating NLRP3 inflammasome and Sirt1/Smad3 deacetylation pathway. METHODS: Four weeks after 5/6 ablation/infarction (A/I) surgery, Sprague-Dawley rats were randomly divided into the following groups: sham operation group, 5/6 (A/I) group, 5/6 (A/I) + SSR group, and 5/6 (A/I) + Losartan group (5/6 (A/I) + Los). After 8 weeks intervention,we mainly assessed the severity of renal injury and fibrosis along with the activation of NLRP3 inflammasome and Sirt1/Smad3 deacetylation pathway. RESULTS: SSR significantly attenuated renal injury and fibrosis in the remnant kidneys. In addition, we found that SSR effectively inhibited activation of NLRP3/ASC/Caspase-1/IL-1ßcascade, decreased inflammatory infiltration and up-regulated Sirt1/Smad3 deacetylation pathway. CONCLUSIONS: SSR could contribute to renal protection by inhibiting the activation of NLRP3 inflammasome and, furthermore, strengthen the antifibrotic effects by up-regulating Sirt1/Smad3 deacetylation pathway in 5/6 renal (A/I) model.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Inflamassomos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Insuficiência Renal Crônica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Proteína Smad3/metabolismo , Acetilação/efeitos dos fármacos , Animais , Fibrose/metabolismo , Rim/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
20.
Mol Plant Microbe Interact ; 32(6): 673-684, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30598046

RESUMO

Mitogen-activated protein kinase (MAPK) cascades serve as unified signaling modules in plant development and defense response. Previous reports demonstrated an essential role of Arabidopsis GLIP1, a member of the GDSL-like-motif lipase family, in both local and systemic resistance. GLIP1 expression is highly induced by pathogen attack. However, the one or more signaling pathways involved are unknown. Here, we report that two pathogen-responsive MAPKs, MPK3 and MPK6, are implicated in regulating gene expression of GLIP1 as well as GLIP3 and GLIP4. After gain-of-function activation, MPK3 and MPK6 can strongly induce the expression of GLIP1, GLIP3, and GLIP4. Both GLIP1 and GLIP3 contribute to the plant resistance to Botrytis cinerea. WRKY33, a MPK3/MPK6 substrate, is essential for the MPK3/MPK6-dependent GLIP1 induction. In addition, WRKY2 and WRKY34, two close homologs of WRKY33, have a minor effect in MPK3/MPK6-regulated GLIP1 expression in B. cinerea-infected plants. Chromatin immunoprecipitation-quantitative polymerase chain reaction analysis demonstrated that the GLIP1 gene is a direct target of WRKY33. In addition, we demonstrated that MPK3/MPK6-induced GLIP1 expression is independent of ethylene and jasmonic acid, two important hormones in plant defense. Our results provide insights into the regulation of the GLIP family at the transcriptional level in plant immunity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Hidrolases de Éster Carboxílico , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Proteínas Quinases Ativadas por Mitógeno , Fatores de Transcrição , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/imunologia , Botrytis/fisiologia , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/imunologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/imunologia , Proteínas Quinases Ativadas por Mitógeno/imunologia , Fatores de Transcrição/imunologia
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