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1.
Plant Physiol ; 194(2): 758-773, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37847103

RESUMO

Touch induces marked morphological changes in plants, including reduced rosette diameters and delayed flowering, a process called thigmomorphogenesis. Previous studies have revealed that thigmomorphogenesis in Arabidopsis (Arabidopsis thaliana) results from touch-induced accumulation of jasmonic acid (JA) and GIBBERELLIN 2-OXIDASE7 (GA2ox7) transcripts, which encode a gibberellin (GA) catabolism enzyme, leading to reduced levels of active GAs. However, the mechanisms underlying thigmomorphogenesis remain uncharacterized. Here, we showed that touch induces ethylene (ET) production in Arabidopsis. After touch treatment, ET biosynthesis and signaling mutants exhibited even greater thigmomorphogenic changes and more decreased GA4 contents than did wild-type (WT) plants. Biochemical analysis indicated that the transcription factor ETHYLENE INSENSITIVE3 (EIN3) of the ET pathway binds to the promoter of GA2ox8 (encoding another GA 2-oxidase performing the same GA modification as GA2ox7) and represses GA2ox8 transcription. Moreover, MYC2, the master regulator of JA signaling, directly promoted GA2ox7 expression by binding the G-box motif on GA2ox7 promoter. Further genetic analysis suggested that the ET and JA pathways independently control the expression of GA2ox8 and GA2ox7, respectively. This study reveals that the ET pathway is a novel repressor of touch-induced thigmomorphogenesis and highlights that the ET and JA pathways converge on GA catabolism but play opposite roles to fine-tune GA4 content during thigmomorphogenesis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Giberelinas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Small ; : e2308964, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38342703

RESUMO

Interface passivation through Lewis acid-base coordinate chemistry in perovskite solar cells (PSCs) is a universal strategy to reduce interface defects and hinder ion migration. However, the formation of coordinate covalent bonding demands strict directional alignment of coordinating atoms. Undoubtedly, this limits the selected range of the interface passivation molecules, because a successful molecular bridge between charge transport layer and perovskite bottom interface needs a well-placed molecular orientation. In this study, it is discovered that potassium ions can migrate to the hollow sites of multiple iodine ions from perovskite to form K-Ix ionic bonding, and the ionic bonds without directionality can support molecular backbone rotation to facilitate polar sites (carboxyl groups) chelating Pb at the bottom perovskite interface, finally forming a closed-loop bonding structure. The synergy of coordinate and ionic bonding significantly reduces interface defects, changes electric field distribution, and immobilizes iodine at the perovskite bottom interface, resulting in eliminating the hysteresis effect and enhancing the performance of PSCs. As a result, the corresponding devices achieve a high efficiency exceeding 24.5% (0.09 cm2 ), and a mini-module with 21% efficiency (12.4 cm2 ). These findings provide guidelines for designing molecular bridging strategies at the buried interface of PSCs.

3.
BMC Genomics ; 24(1): 380, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37415142

RESUMO

BACKGROUND: Microspore embryogenesis is an extraordinarily complicated process, comprehensively regulated by a composite network of physiological and molecular factors, among which hormone is one of the most crucial factors. Auxin is required for stress-induced microspore reprogramming, however, the mechanism of its regulation of microspore embryogenesis is still unclear. RESULTS: In this study, we found exogenously spraying 100 mg·L- 1 IAA on the buds of Wucai significantly increased the rate of microspore embryogenesis, and moreover accelerated the process of embryogenesis. Physiological and biochemical tests showed that the contents of amino acids, soluble total sugar, soluble protein, and starch were significantly increased after IAA treatment. Furthermore, exogenously spraying 100 mg·L- 1 IAA significantly enhanced IAA, GA4, and GA9 content, increased catalase (CAT) and malondialdehyde (MDA) activity, and reduced abscisic acid (ABA), MDA and soluble protopectin content, H2O2 and O2·- production rate in the bud with the largest population of late-uninucleate-stage microspores. Transcriptome sequencing was performed on buds respectively treated with 100 mg·L- 1 IAA and fresh water. A total of 2004 DEGs were identified, of which 79 were involved in micropores development, embryonic development and cell wall formation and modification, most of which were upregulated. KEGG and GO analysis revealed that 9.52% of DEGs were enriched in plant hormone synthesis and signal transduction pathways, pentose and glucuronic acid exchange pathways, and oxidative phosphorylation pathways. CONCLUSIONS: These findings indicated that exogenous IAA altered the contents of endogenous hormone content, total soluble sugar, amino acid, starch, soluble protein, MDA and protopectin, the activities of CAT and peroxidase (POD), and the production rate of H2O2 and O2·-. Combined with transcriptome analysis, it was found that most genes related to gibberellin (GA) and Auxin (IAA) synthesis and signal transduction, pectin methylase (PME) and polygalacturonase (PGs) genes and genes related to ATP synthesis and electron transport chain were upregulated, and genes related to ABA synthesis and signal transduction were downregulated. These results indicated that exogenous IAA treatment could change the balance of endogenous hormones, accelerate cell wall degradation, promote ATP synthesis and nutrient accumulation, inhibit ROS accumulation, which ultimately promote microspore embryogenesis.


Assuntos
Brassica , Brassica/metabolismo , Peróxido de Hidrogênio/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Amido/metabolismo , Metabolismo Energético , Hormônios/metabolismo , Parede Celular/metabolismo , Trifosfato de Adenosina/metabolismo
4.
J Pharmacol Exp Ther ; 385(2): 106-116, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36849412

RESUMO

Individuals with neurofibromatosis type 1 develop rat sarcoma virus (RAS)-mitogen-activated protein kinase-mitogen-activated and extracellular signal-regulated kinase (RAS-MAPK-MEK)-driven nerve tumors called neurofibromas. Although MEK inhibitors transiently reduce volumes of most plexiform neurofibromas in mouse models and in neurofibromatosis type 1 (NF1) patients, therapies that increase the efficacy of MEK inhibitors are needed. BI-3406 is a small molecule that prevents Son of Sevenless (SOS)1 interaction with Kirsten rat sarcoma viral oncoprotein (KRAS)-GDP, interfering with the RAS-MAPK cascade upstream of MEK. Single agent SOS1 inhibition had no significant effect in the DhhCre;Nf1 fl/fl mouse model of plexiform neurofibroma, but pharmacokinetics (PK)-driven combination of selumetinib with BI-3406 significantly improved tumor parameters. Tumor volumes and neurofibroma cell proliferation, reduced by MEK inhibition, were further reduced by the combination. Neurofibromas are rich in ionized calcium binding adaptor molecule 1 (Iba1)+ macrophages; combination treatment resulted in small and round macrophages, with altered cytokine expression indicative of altered activation. The significant effects of MEK inhibitor plus SOS1 inhibition in this preclinical study suggest potential clinical benefit of dual targeting of the RAS-MAPK pathway in neurofibromas. SIGNIFICANCE STATEMENT: Interfering with the RAS-mitogen-activated protein kinase (RAS-MAPK) cascade upstream of mitogen activated protein kinase kinase (MEK), together with MEK inhibition, augment effects of MEK inhibition on neurofibroma volume and tumor macrophages in a preclinical model system. This study emphasizes the critical role of the RAS-MAPK pathway in controlling tumor cell proliferation and the tumor microenvironment in benign neurofibromas.


Assuntos
Neurofibroma Plexiforme , Neurofibroma , Neurofibromatose 1 , Animais , Camundongos , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno , Neurofibroma/tratamento farmacológico , Neurofibroma Plexiforme/tratamento farmacológico , Neurofibromatose 1/tratamento farmacológico , Neurofibromatose 1/patologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/uso terapêutico , Microambiente Tumoral , Proteína SOS1/metabolismo
5.
Cell Mol Biol (Noisy-le-grand) ; 69(9): 207-212, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37807312

RESUMO

The purpose of this study arose to investigate the mechanism of miR-204-5p targeting P4HB to regulate inflammation and apoptosis in HUVEC cells. Serum specimens were obtained from lower extremity DVT patients and healthy subjects. Targetscan predicted P4HB as a target gene for miR-204-5p. A dual luciferase reporter assay was conducted to determine the modulating effect of miR-204-5p on P4HB. qRT-PCR was used to detect miR-204-5p and P4HB expression. Established CoCl2-induced hypoxia/ischemia model of HUVEC, transfected with miR-204-5p mimics and pcDNA3. 1-P4HB. CCK-8 assay for cell viability. Apoptosis was assayed by flow cytometry, western blot and western blot. Immunofluorescence and ELISA were carried out to detect ROS, MDA, SOD, LDH, GSH-px, TNF-α, IL-1ß and IL-6 expression. miR-204-5p was reduced markedly in the sera of DVT patients. miR-204-5p negatively regulated P4HB. P4HB expression was raised in the sera of DVT patients. Exposure to CoCl2 decreased miR-204-5p expression and increased P4HB in HUVEC. Over-expressed miR-204-5p effectively increased cell viability and inhibited apoptosis; its effect was counteracted by continued overexpression of P4HB. In addition, miR- 204-5p mimics clearly reduced CoCl2-induced ROS and inflammation, and pcDNA3. 1-P4HB acted counteractively. miR-204-5p may inhibit HUVEC proliferation, ROS generation and cellular inflammation through negative regulation of P4HB. miR-204-5p promises to become a potential target for DVT therapy.


Assuntos
Apoptose , Inflamação , MicroRNAs , Humanos , Cobalto/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Inflamação/metabolismo , MicroRNAs/metabolismo , Pró-Colágeno-Prolina Dioxigenase/farmacologia , Isomerases de Dissulfetos de Proteínas/farmacologia , Espécies Reativas de Oxigênio
6.
Proc Natl Acad Sci U S A ; 117(37): 23125-23130, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32868415

RESUMO

Many plants use environmental cues, including seasonal changes of day length (photoperiod), to control their flowering time. Under inductive conditions, FLOWERING LOCUS T (FT) protein is synthesized in leaves, and FT protein is a mobile signal, which is able to travel to the shoot apex to induce flowering. Dodders (Cuscuta, Convolvulaceae) are root- and leafless plants that parasitize a large number of autotrophic plant species with varying flowering time. Remarkably, some dodder species, e.g., Cuscuta australis, are able to synchronize their flowering with the flowering of their hosts. Detailed sequence inspection and expression analysis indicated that the FT gene in dodder C. australis very likely does not function in activating flowering. Using soybean host plants cultivated under inductive and noninductive photoperiod conditions and soybean and tobacco host plants, in which FT was overexpressed and knocked out, respectively, we show that FT-induced flowering of the host is likely required for both host and parasite flowering. Biochemical analysis revealed that host-synthesized FT signals are able to move into dodder stems, where they physically interact with a dodder FD transcription factor to activate dodder flowering. This study demonstrates that FTs can function as an important interplant flowering signal in host-dodder interactions. The unique means of flowering regulation of dodder illustrates how regressive evolution, commonly found in parasites, may facilitate the physiological synchronization of parasite and host, here allowing the C. australis parasite to time reproduction exactly with that of their hosts, likely optimizing parasite fitness.


Assuntos
Cuscuta/fisiologia , Cuscuta/parasitologia , Flores/fisiologia , Flores/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Parasitos/fisiologia , Animais , Regulação da Expressão Gênica de Plantas/fisiologia , Folhas de Planta/parasitologia , Folhas de Planta/fisiologia , Glycine max/parasitologia , Glycine max/fisiologia , Nicotiana/parasitologia , Nicotiana/fisiologia , Fatores de Transcrição/metabolismo
7.
BMC Surg ; 23(1): 284, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726737

RESUMO

BACKGROUND AND AIMS: Laparoscopic resection has been reported as effective and safe for gastric schwannoma (GS) in the form of case reports. However, study on laparoscopic surgery in patients with GS larger than 30 mm has been rarely reported. To this end, the present study aimed to evaluate the safety and efficacy of laparoscopic resection for the treatment of GS larger than 30 mm and its long-term outcomes. METHODS: This is a retrospective case series study of patients with GS larger than 30 mm who underwent laparoscopic resection at our hospital between January 2014 and December 2020. Clinical pathology, surgical and follow-up data were collected and analyzed. RESULTS: A total of 10 patients with a mean age of 51.6 years were included. Seven tumors were located in gastric body, 2 in antrum and 1 in fundus. Laparoscopic gastric wedge resection was performed in 7 patients, while laparoscopic gastric local resection was performed in 3 patients. All patients achieved complete resection. The mean operation time was 112.6 ± 34.3 min, and the mean postoperative hospital stay was 13.8 ± 5.1 days. Postoperative gastroplegia occurred in 2 patients and was treated with conservative therapy. No recurrence, metastasis or residue was found during the follow-up of mean 45.1 months. CONCLUSIONS: Laparoscopic resection is a safe and effective method for treating GS larger than 30 mm with favorable long-term follow-up outcomes. Laparoscopic resection may be considered as the first-line treatment for GS larger than 30 mm.


Assuntos
Neoplasias do Sistema Digestório , Laparoscopia , Neurilemoma , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Neurilemoma/cirurgia , Gastrectomia
8.
Int J Mol Sci ; 24(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37373399

RESUMO

Abdominal aortic aneurysm (AAA) is hallmarked by irreversible dilation of the infrarenal aorta. Lipid deposition in the aortic wall and the potential importance of a lipid disorder in AAA etiology highlight the need to explore lipid variation during AAA development. This study aimed to systematically characterize the lipidomics associated with AAA size and progression. Plasma lipids from 106 subjects (36 non-AAA controls and 70 AAA patients) were comprehensively analyzed using untargeted lipidomics. An AAA animal model was established by embedding angiotensin-II pump in ApoE-/- mice for four weeks and blood was collected at 0, 2 and 4 weeks for lipidomic analysis. Using a false-discovery rate (FDR) < 0.05, a group of lysophosphatidylcholines (lysoPCs) were specifically decreased in AAA patients and mice. LysoPCs were principally lower in the AAA patients with larger diameter (diameter > 50 mm) than those with a smaller size (30 mm < diameter < 50 mm), and levels of lysoPCs were also found to be decreased with modelling time and aneurysm formation in AAA mice. Correlation matrices between lipids and clinical characteristics identified that the positive correlation between lysoPCs and HDL-c was reduced and negative correlations between lysoPCs and CAD rate, lysoPCs and hsCRP were converted to positive correlations in AAA compared to control. Weakened positive correlations between plasma lysoPCs and circulating HDL-c in AAA suggested that HDL-lysoPCs may elicit instinctive physiological effects in AAA. This study provides evidence that reduced lysoPCs essentially underlie the pathogenesis of AAA and that lysoPCs are promising biomarkers for AAA development.


Assuntos
Aneurisma da Aorta Abdominal , Lipidômica , Camundongos , Animais , Lisofosfatidilcolinas , Aneurisma da Aorta Abdominal/patologia , Aorta Abdominal , Biomarcadores , Angiotensina II , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
9.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36902245

RESUMO

Wucai (Brassica campestris L.) is a leafy vegetable that originated in China, its soluble sugars accumulate significantly to improve taste quality during maturation, and it is widely accepted by consumers. In this study, we investigated the soluble sugar content at different developmental stages. Two periods including 34 days after planting (DAP) and 46 DAP, which represent the period prior to and after sugar accumulation, respectively, were selected for metabolomic and transcriptomic profiling. Differentially accumulated metabolites (DAMs) were mainly enriched in the pentose phosphate pathway, galactose metabolism, glycolysis/gluconeogenesis, starch and sucrose metabolism, and fructose and mannose metabolism. By orthogonal projection to latent structures-discriminant s-plot (OPLS-DA S-plot) and MetaboAnalyst analyses, D-galactose and ß-D-glucose were identified as the major components of sugar accumulation in wucai. Combined with the transcriptome, the pathway of sugar accumulation and the interact network between 26 DEGs and the two sugars were mapped. CWINV4, CEL1, BGLU16, and BraA03g023380.3C had positive correlations with the accumulation of sugar accumulation in wucai. The lower expression of BraA06g003260.3C, BraA08g002960.3C, BraA05g019040.3C, and BraA05g027230.3C promoted sugar accumulation during the ripening of wucai. These findings provide insights into the mechanisms underlying sugar accumulation during commodity maturity, providing a basis for the breeding of sugar-rich wucai cultivars.


Assuntos
Brassica , Açúcares , Açúcares/metabolismo , Brassica/genética , Melhoramento Vegetal , Perfilação da Expressão Gênica , Transcriptoma , Metaboloma , Regulação da Expressão Gênica de Plantas
10.
J Integr Plant Biol ; 65(4): 1041-1058, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36349965

RESUMO

Both herbivory and jasmonic acid (JA) activate the biosynthesis of defensive metabolites in maize, but the mechanism underlying this remains unclear. We generated maize mutants in which ZmMYC2a and ZmMYC2b, two transcription factor genes important in JA signaling, were individually or both knocked out. Genetic and biochemical analyses were used to elucidate the functions of ZmMYC2 proteins in the maize response to simulated herbivory and JA. Compared with the wild-type (WT) maize, the double mutant myc2ab was highly susceptible to insects, and the levels of benzoxazinoids and volatile terpenes, and the levels of their biosynthesis gene transcripts, were much lower in the mutants than in the WT maize after simulated insect feeding or JA treatment. Moreover, ZmMYC2a and ZmMYC2b played a redundant role in maize resistance to insects and JA signaling. Transcriptome and Cleavage Under Targets and Tagmentation-Sequencing (CUT&Tag-Seq) analysis indicated that ZmMYC2s physically targeted 60% of the JA-responsive genes, even though only 33% of these genes were transcriptionally ZmMYC2-dependent. Importantly, CUT&Tag-Seq and dual luciferase assays revealed that ZmMYC2s transactivate the benzoxazinoid and volatile terpene biosynthesis genes IGPS1/3, BX10/11/12/14, and TPS10/2/3/4/5/8 by directly binding to their promoters. Furthermore, several transcription factors physically targeted by ZmMYC2s were identified, and these are likely to function in the regulation of benzoxazinoid biosynthesis. This work reveals the transcriptional regulatory landscapes of both JA signaling and ZmMYC2s in maize and provides comprehensive mechanistic insight into how JA signaling modulates defenses in maize responses to herbivory through ZmMYC2s.


Assuntos
Adaptação Fisiológica , Regulação da Expressão Gênica de Plantas , Herbivoria , Zea mays , Animais , Benzoxazinas/metabolismo , Ciclopentanos/metabolismo , Insetos/fisiologia , Oxilipinas/metabolismo , Zea mays/genética , Zea mays/metabolismo , Adaptação Fisiológica/genética
11.
Plant J ; 108(6): 1609-1623, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34647389

RESUMO

Mycoheterotrophic and parasitic plants are heterotrophic and parasitize on fungi and plants, respectively, to obtain nutrients. Large-scale comparative genomics analysis has not been conducted in mycoheterotrophic or parasitic plants or between these two groups of parasites. We assembled a chromosome-level genome of the fully mycoheterotrophic plant Gastrodia elata (Orchidaceae) and performed comparative genomic analyses on the genomes of G. elata and four orchids (initial mycoheterotrophs), three parasitic plants (Cuscuta australis, Striga asiatica, and Sapria himalayana), and 36 autotrophs from various angiosperm lineages. It was found that while in the hemiparasite S. asiatica and initial mycoheterotrophic orchids, approximately 4-5% of the conserved orthogroups were lost, the fully heterotrophic G. elata and C. australis both lost approximately 10% of the conserved orthogroups, indicating that increased heterotrophy is positively associated with gene loss. Importantly, many genes that are essential for autotrophs, including those involved in photosynthesis, the circadian clock, flowering time regulation, immunity, nutrient uptake, and root and leaf development, were convergently lost in both G. elata and C. australis. The high-quality genome of G. elata will facilitate future studies on the physiology, ecology, and evolution of mycoheterotrophic plants, and our findings highlight the critical role of gene loss in the evolution of plants with heterotrophic lifestyles.


Assuntos
Gastrodia/genética , Genes de Plantas , Genoma de Planta , Processos Heterotróficos/genética , Cromossomos de Plantas , Relógios Circadianos/genética , Evolução Molecular , Flores/genética , Flores/fisiologia , Gastrodia/fisiologia , Genômica , Íntrons , Magnoliopsida/genética , Magnoliopsida/fisiologia , Anotação de Sequência Molecular , Família Multigênica , Fotossíntese/genética , Imunidade Vegetal/genética , Striga/genética , Striga/fisiologia , Simbiose/genética
12.
Plant Physiol ; 185(4): 1395-1410, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33793912

RESUMO

Dodder (Cuscuta spp., Convolvulaceae) is a genus of parasitic plants with worldwide distribution. Dodders are able to simultaneously parasitize two or more adjacent hosts, forming dodder-connected plant clusters. Nitrogen (N) deficiency is a common challenge to plants. To date, it has been unclear whether dodder transfers N-systemic signals between hosts grown in N-heterogeneous soil. Transcriptome and methylome analyses were carried out to investigate whether dodder (Cuscuta campestris) transfers N-systemic signals between N-replete and N-depleted cucumber (Cucumis sativus) hosts, and it was found that N-systemic signals from the N-deficient cucumber plants were rapidly translocated through C. campestris to the N-replete cucumber plants. Unexpectedly, certain systemic signals were also transferred from the N-replete to N-depleted cucumber hosts. We demonstrate that these systemic signals are able to regulate large transcriptome and DNA methylome changes in the recipient hosts. Importantly, N stress also induced many long-distance mobile mRNA transfers between C. campestris and hosts, and the bilateral N-systemic signaling between N-replete and N-depleted hosts had a strong impact on the inter-plant mobile mRNAs. Our 15N labeling experiment indicated that under N-heterogeneous conditions, N-systemic signals from the N-deficient cucumber hosts did not obviously change the N-uptake activity of the N-replete cucumber hosts; however, in plant clusters comprising C. campestris-connected cucumber and soybean (Glycine max) plants, if the soybean plants were N-starved, the cucumber plants exhibited increased N-uptake activity. This study reveals that C. campestris facilitates plant-plant communications under N-stress conditions by enabling extensive bilateral N-systemic signaling between different hosts.


Assuntos
Cuscuta/genética , Cuscuta/fisiologia , Cuscuta/parasitologia , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/fisiologia , Proteínas PII Reguladoras de Nitrogênio/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas PII Reguladoras de Nitrogênio/genética
13.
J Exp Bot ; 73(22): 7611-7627, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36214841

RESUMO

Herbivory activates responses in local and systemic leaves, and the glutamate receptor-like genes GLR3.3 and GLR3.6 are critical in leaf-to-leaf systemic signalling. However, whether and how these genes mediate plant systemic resistance to insects remain largely unexplored. We show that a piercing-sucking insect Myzus persicae (green peach aphid, GPA) or chewing insect Spodoptera litura (cotton leafworm, CLW) feeding-induced systemic defences were attenuated in the glr3.3 glr3.6 mutants. In response to herbivory from either insect, glr3.3 glr3.6 mutants exhibited reduced accumulation of the hormone jasmonic acid (JA) and defensive metabolites glucosinolates (GSs) in systemic (but not local) leaves. Transcriptome analysis indicated that GLR3.3 and GLR3.6 play an important role in regulating the transcriptional responses to GPA and simulated CLW feeding in both local and systemic leaves, including JA- and GS-related genes. Metabolome analysis also revealed that in response to GPA or simulated CLW feeding, GLR3.3 and GLR3.6 are involved in the regulation of various metabolites locally and systemically, including amino acids, carbohydrates, and organic acids. Taken together, this study provides new insights into the function of GLR3.3 and GLR3.6 in mediating transcripts and metabolites in local and systemic leaves under insect attack, and highlights their role in regulating insect resistance in systemic leaves.


Assuntos
Arabidopsis , Animais , Arabidopsis/genética , Insetos , Receptores de Glutamato
14.
BMC Infect Dis ; 22(1): 227, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35255852

RESUMO

BACKGROUND: Epstein-Barr virus (EBV) infects more than 90% of the population worldwide. However, chronic active EBV infection (CAEBV) is one of the EBV-positive T- or NK-lymphoproliferative diseases with high morbidity and mortality. Here, we report a case of a 9-year girl with CAEBV, successively presenting with polymyositis and coronary artery dilation (CAD). CASE PRESENTATION: The girl complained of fatigue for more than 1 month. Muscle strength examinations had no abnormal findings. Blood chemistries showed elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatine kinase (CK). Magnetic resonance imaging (MRI) showed spotty high-intensity signals in thigh muscles, and electromyogram suggested myogenic damage. The significant findings were positive EBV antibodies (EBVEA-IgG, EBVCA-IgG, and EBVNA-IgG), increased EBV DNA copies in B, T, and NK cells, and positive EBV-encoded small RNA in biopsy muscle specimen. The girl received ganciclovir, intravenous immunoglobulin, and methylprednisolone, and her symptoms improved. On the 45th day of hospitalization, echocardiograph revealed CAD. She received additional anticoagulants and Tocilizumab. Her condition improved and continued to be followed up at the clinic preparing for hematopoietic stem cell transplantation. CONCLUSIONS: This is the first reported case of CAEBV successively with polymyositis and CAD. This case makes the diagnoses of autoimmune diseases in children more complicated. Careful investigation of hidden CAEBV should be recommended in children with atypical polymyositis or CAD.


Assuntos
Infecções por Vírus Epstein-Barr , Polimiosite , Doença Crônica , Vasos Coronários , Dilatação , Feminino , Herpesvirus Humano 4/genética , Humanos , Polimiosite/complicações
15.
Int J Mol Sci ; 23(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36293280

RESUMO

Polyamine oxidases (PAOs) are key enzymes in polyamine metabolism and are related to the tolerance of plants to abiotic stresses. In this study, overexpression of cucumber (Cucumis sativus L.) PAO2 (CsPAO2) in Arabidopsis resulted in increased activity of the antioxidant enzyme and accelerated conversion from Put to Spd and Spm, while malondialdehyde content (MDA) and electrolyte leakage (EL) was decreased when compared with wild type, leading to enhanced plant growth under salt stress. Photosystem Ⅰ assembly 3 in cucumber (CsPSA3) was revealed as an interacting protein of CsPAO2 by screening yeast two-hybrid library combined with in vitro and in vivo methods. Then, CsPAO2 and CsPSA3 were silenced in cucumber via virus-mediated gene silencing (VIGS) with pV190 as the empty vector. Under salt stress, net photosynthetic rate (Pn) and transpiration rate (Tr) of CsPAO2-silencing plants were lower than pV190-silencing plants, and EL in root was higher than pV190-silencing plants, indicating that CsPAO2-silencing plants suffered more serious salt stress damage. However, photosynthetic parameters of CsPSA3-silencing plants were all higher than those of CsPAO2 and pV190-silencing plants, thereby enhancing the photosynthesis process. Moreover, CsPSA3 silencing reduced the EL in both leaves and roots when compared with CsPAO2-silencing plants, but the EL only in leaves was significantly lower than the other two gene-silencing plants, and conversion from Put to Spd and Spm in leaf was also promoted, suggesting that CsPSA3 interacts with CsPAO2 in leaves to participate in the regulation of salt tolerance through photosynthesis and polyamine conversion.


Assuntos
Cucumis sativus , Cucumis sativus/metabolismo , Tolerância ao Sal/genética , Poliaminas/metabolismo , Antioxidantes/metabolismo , Complexo de Proteína do Fotossistema I/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Oxirredutases/metabolismo , Malondialdeído/metabolismo , Oxigênio/metabolismo , Plântula/genética
16.
Mod Rheumatol ; 32(6): 1114-1121, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34971386

RESUMO

OBJECTIVES: To evaluate the safety and efficacy of tocilizumab (TCZ) on refractory macrophage activation syndrome (rMAS) associated with systemic juvenile idiopathic arthritis (sJIA-rMAS). METHODS: We retrospectively reviewed the charts of 14 patients diagnosed with sJIA-rMAS, who were treated with TCZ after failing conventional therapies at three hospital centres from January 2016 to December 2020. Demographic, clinical, and laboratory characteristics were recorded at the onset of MAS, before TCZ (pre-TCZ), and 14 days after TCZ (post-TCZ). RESULTS: The clinical manifestation of sJIA-rMAS included fever (100%), skin rashes (35.7%), lymphadenomegaly (42.9%), hepatomegaly (57.1%), splenomegaly (7.1%), gastrointestinal symptoms (28.6%), arthritis (14.3%), myalgia (28.6%), and polyserositis (14.3%). After TCZ treatment, fever (100%, 14/14), gastrointestinal symptoms (100%, 4/4), and myalgia (100%, 4/4) were significantly improved after 1 week (P < 0.05). Skin rashes, lymphadenomegaly, and arthritis also improved in many patients, but these parameters did not reach statistical significance. In post-TCZ group, decreases in levels of C-reactive protein, erythrocyte sedimentation rate, and serum ferritin of sJIA-rMAS were observed compared with pre-TCZ (P < 0.05). No disease relapse or fatality was recorded during the follow-up (25 months, range 3-60 months). CONCLUSIONS: TCZ is safe and effective for the treatment of sJIA-rMAS after failure of conventional therapies.


Assuntos
Artrite Juvenil , Síndrome de Ativação Macrofágica , Anticorpos Monoclonais Humanizados , Artrite Juvenil/complicações , Artrite Juvenil/diagnóstico , Artrite Juvenil/tratamento farmacológico , Proteína C-Reativa , Ferritinas , Humanos , Síndrome de Ativação Macrofágica/complicações , Síndrome de Ativação Macrofágica/tratamento farmacológico , Mialgia/complicações , Estudos Retrospectivos
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(6): 1075-1081, 2022 Dec.
Artigo em Zh | MEDLINE | ID: mdl-36373641

RESUMO

Abdominal aortic aneurysm(AAA) is a chronic dilated artery disease induced by atherosclerosis,infection,trauma and other related causes.The available studies about AAA mainly focus on the inflammatory response,senility,and microenvironmental changes,while the research on the metabolic changes such as glucose metabolism and lipid metabolism remains to be conducted.As a critical regulatory factor in endocrine,glucose,and lipid metabolisms,leptin is associated with a variety of signaling pathways such as adenosine monophosphate-activated protein kinase,Janus kinase/signal transducer and activator of transcription,and cytokine-cytokine receptor,as demonstrated by the KEGG pathway enrichment analysis.Moreover,these signaling pathways are generally involved in regulating the occurrence of AAA.In addition,leptin affects the occurrence of a variety of diseases such as obesity,diabetes,and hyperlipidemia,which contribute to the formation of AAA.Diabetes might be a protective factor for the formation of AAA,while the relationship of hyperlipidemia and obesity with the formation of AAA remains unclear.Therefore,leptin might play an essential role in the formation of AAA.Further studies about the effect of leptin on AAA may provide the potential research direction and facilitate the discovery of therapeutic targets.


Assuntos
Aneurisma da Aorta Abdominal , Diabetes Mellitus , Aorta Abdominal/metabolismo , Leptina/efeitos adversos , Obesidade , Transdução de Sinais , Humanos
18.
Br J Cancer ; 125(8): 1111-1121, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34365472

RESUMO

BACKGROUND AND AIMS: Computed tomography (CT) scan is frequently used to detect hepatocellular carcinoma (HCC) in routine clinical practice. The aim of this study is to develop a deep-learning AI system to improve the diagnostic accuracy of HCC by analysing liver CT imaging data. METHODS: We developed a deep-learning AI system by training on CT images from 7512 patients at Henan Provincial Peoples' Hospital. Its performance was validated on one internal test set (Henan Provincial Peoples' Hospital, n = 385) and one external test set (Henan Provincial Cancer Hospital, n = 556). The area under the receiver-operating characteristic curve (AUROC) was used as the primary classification metric. Accuracy, sensitivity, specificity, precision, negative predictive value and F1 metric were used to measure the performance of AI systems and radiologists. RESULTS: AI system achieved high performance in identifying HCC patients, with AUROC of 0.887 (95% CI 0.855-0.919) on the internal test set and 0.883 (95% CI 0.855-0.911) on the external test set. For internal test set, accuracy was 81.0% (76.8-84.8%), sensitivity was 78.4% (72.4-83.7%), specificity was 84.4% (78.0-89.6%) and F1 (harmonic average of precision and recall rate) was 0.824. For external test set, accuracy was 81.3% (77.8-84.5%), sensitivity was 89.4% (85.0-92.8%), specificity was 74.0% (68.5-78.9%) and F1 was 0.819. Compared with radiologists, AI system achieved comparable accuracy and F1 metric on internal test set (0.853 versus 0.818, P = 0.107; 0.863 vs. 0.824, P = 0.082) and external test set (0.805 vs. 0.793, P = 0.663; 0.810 vs. 0.814, P = 0.866). The predicted HCC risk scores by AI system in HCC patients with multiple tumours and high fibrosis stage were higher than those with solitary tumour and low fibrosis stage (tumour number: 0.197 vs. 0.138, P = 0.006; fibrosis stage: 0.183 vs. 0.127, P < 0.001). Radiologists' review showed that the accuracy of saliency heatmaps predicted by algorithms was 92.1% (95% CI: 89.2-95.0%). CONCLUSIONS: AI system achieved high performance in the detection of HCC compared with a group of specialised radiologists. Further investigation by prospective clinical trials was necessitated to verify this model.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Inteligência Artificial , Criança , Pré-Escolar , Aprendizado Profundo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
19.
Expert Rev Proteomics ; 18(4): 305-314, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33840337

RESUMO

Introduction: Abdominal aortic aneurysm (AAA) is a common, complex, and life-threatening disease. Currently, the pathogenesis of AAA is not well understood. No biomarkers or specific drugs are available for AAA in clinical applications. Proteomics is a powerful tool in biomarker discovery, exploration of pathogenesis, and drug target identification.Areas covered: We review the application of mass spectrometry-based proteome analysis in AAA patients within the last ten years. Differentially expressed proteins associated with AAA were identified in multiple sample sources, including vascular tissue, intraluminal thrombus, tissue secretome, blood, and cells. Some potential disease biomarkers, pathogenic mechanisms, or therapeutic targets for AAA were discovered using proteome analysis. The challenges and prospects of proteomics applied to AAA are also discussed.Expert opinion: Since most of the previous proteomic studies used relatively small sample sizes, some promising biomarkers need to be validated in multicenter cohorts to accelerate their clinical application. With the rapid development of mass spectrometry technology, modification-specific proteomics and multi-omics research in the future will enhance our understanding of the pathogenesis of AAA and promote biomarker discovery and drug development for clinical translation.


Assuntos
Aneurisma da Aorta Abdominal , Proteômica , Biomarcadores , Humanos , Espectrometria de Massas , Estudos Multicêntricos como Assunto , Proteoma
20.
New Phytol ; 229(4): 2273-2287, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32996127

RESUMO

2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) and DIMBOA-glucoside (DIMBOA-Glc) are anti-insect benzoxazinoids in maize, yet very little information is known about how they are regulated. Reverse genetics, kinase activity analysis, phytohormone and DIMBOA/DIMBOA-Glc quantification, bioassays and transcriptome analysis were employed to study the function of ZmMPK6, a mitogen-activated protein kinase, in maize response to herbivory. ZmMPK6 was rapidly activated by wounding and simulated herbivory. Silencing ZmMPK6 in maize A188 compromised simulated herbivory-induced ethylene levels but not those of jasmonic acid or salicylic acid, and the ZmMPK6-silenced plants exhibited elevated DIMBOA/DIMBOA-Glc and insect resistance. An ethylene complementation experiment revealed that ZmMPK6 repressed the accumulation of DIMBOA/DIMBOA-Glc in an ethylene-dependent manner. Transcriptome analysis revealed that ZmMPK6 might meditate the transcription of BX1 by controlling a MYB transcription factor that is likely to be located in the ethylene signalling pathway and, furthermore, ZmMPK6 and ethylene signalling also specifically and commonly regulate the transcription of other benzoxazinoid biosynthetic genes. We also show that different maize lines have very different responses to simulated herbivory in terms of ZmMPK6 activation, ethylene emission and benzoxazinoid levels. These results uncover that ZmMPK6 and ethylene pathway are novel repressors of DIMBOA/DIMBOA-Glc and provide new insight into the regulatory mechanisms underlying these two pathways.


Assuntos
Benzoxazinas , Zea mays , Animais , Etilenos , Glucosídeos , Insetos , Zea mays/genética
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