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1.
Plant Physiol ; 192(3): 1913-1927, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-36843134

RESUMO

Chlorophyll degradation and anthocyanin biosynthesis, which often occur almost synchronously during fruit ripening, are crucial for vibrant coloration of fruits. However, the interlink point between their regulatory pathways remains largely unknown. Here, 2 litchi (Litchi chinensis Sonn.) cultivars with distinctively different coloration patterns during ripening, i.e. slow-reddening/stay-green "Feizixiao" (FZX) vs rapid-reddening/degreening "Nuomici" (NMC), were selected as the materials to study the key factors determining coloration. Litchi chinensis STAY-GREEN (LcSGR) was confirmed as the critical gene in pericarp chlorophyll loss and chloroplast breakdown during fruit ripening, as LcSGR directly interacted with pheophorbide a oxygenase (PAO), a key enzyme in chlorophyll degradation via the PAO pathway. Litchi chinensis no apical meristem (NAM), Arabidopsis transcription activation factor 1/2, and cup-shaped cotyledon 2 (LcNAC002) was identified as a positive regulator in the coloration of litchi pericarp. The expression of LcNAC002 was significantly higher in NMC than in FZX. Virus-induced gene silencing of LcNAC002 significantly decreased the expression of LcSGR as well as L. chinensis MYELOBLASTOSIS1 (LcMYB1), and inhibited chlorophyll loss and anthocyanin accumulation. A dual-luciferase reporter assay revealed that LcNAC002 significantly activates the expression of both LcSGR and LcMYB1. Furthermore, yeast-one-hybrid and electrophoretic mobility shift assay results showed that LcNAC002 directly binds to the promoters of LcSGR and LcMYB1. These findings suggest that LcNAC002 is an important ripening-related transcription factor that interlinks chlorophyll degradation and anthocyanin biosynthesis by coactivating the expression of both LcSGR and LcMYB1.


Assuntos
Antocianinas , Litchi , Antocianinas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Litchi/genética , Frutas/genética , Regulação da Expressão Gênica de Plantas , Clorofila/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
J Exp Bot ; 74(12): 3613-3629, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-36928543

RESUMO

In flowering plants, floral induction signals intersect at the shoot apex to modulate meristem determinacy and growth form. Here, we report a single-nucleus RNA sequence analysis of litchi apical buds at different developmental stages. A total of 41 641 nuclei expressing 21 402 genes were analyzed, revealing 35 cell clusters corresponding to 12 broad populations. We identify genes associated with floral transition and propose a model that profiles the key events associated with litchi floral meristem identity by analyzing 567 identified floral meristem cells at single cell resolution. Interestingly, single-nucleus RNA-sequencing data indicated that all putative FT and TFL1 genes were not expressed in bud nuclei, but significant expression was detected in bud samples by RT-PCR. Based on the expression patterns and gene silencing results, we highlight the critical role of LcTFL1-2 in inhibiting flowering and propose that the LcFT1/LcTFL1-2 expression ratio may determine the success of floral transition. In addition, the transport of LcFT1 and LcTFL1-2 mRNA from the leaf to the shoot apical meristem is proposed based on in situ and dot-blot hybridization results. These findings allow a more comprehensive understanding of the molecular events during the litchi floral transition, as well as the identification of new regulators.


Assuntos
Flores , Litchi , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Folhas de Planta/metabolismo , Análise de Sequência de RNA/métodos , Meristema , Regulação da Expressão Gênica de Plantas
3.
Ann Gen Psychiatry ; 22(1): 3, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36721207

RESUMO

BACKGROUND: Sleep disorders are common during the outbreak of pandemic diseases, and similar disorders are noted in hospitalized COVID-19 patients. It is valuable to explore the clinical manifestations and risk factors for sleep disorders in COVID-19 patients. METHODS: Inpatients with COVID-19 were enrolled. Detailed clinical information was collected, and sleep quality was assessed by PSQI. Patients were divided into a sleep disorder group and a normal group based on a PSQI ≥ 7, and the clinical features were compared between the groups. RESULTS: Fifty-three patients were enrolled, and 47.2% presented sleep disorders. Sleep disorders were associated with older age (> 50), anemia and carbon dioxide retention. Furthermore, factors associated with abnormal component scores of the PSQI were: (1) patients with older age were more likely to have decreased sleep quality, prolonged sleep latency, decreased sleep efficiency, sleep disturbances, and daytime dysfunction; (2) decreased sleep quality and prolonged sleep latency were associated with dyspnea, whereas carbon dioxide retention and more lobes involved in chest CT were associated with prolonged sleep latency; (3) decreased sleep efficiency was more prevalent in patients with anemia. CONCLUSIONS: Sleep disorders were prevalent in patients during the acute phase of COVID-19, and many risk factors (older age, anemia, carbon dioxide retention, the number of lobes involved in chest CT, and dyspnea) were identified. It is important to assess the presence of sleep disorders in patients to provide early intervention.

4.
Pestic Biochem Physiol ; 194: 105503, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532323

RESUMO

Glyphodes pyloalis Walker (G. pyloalis) is a common destructive mulberry pest. Due to the long-term and frequent use of insecticides, it has developed tolerance to commonly used insecticides. Tolfenpyrad (TFP) is a novel pyrazole heterocyclic insecticide. In order to understand the TFP detoxification mechanism of G. pyloalis larvae, we first estimated the LC30 dose of TFP for 3rd instar G. pyloalis larvae. Next, we identified genes that were differentially expressed in 3rd instar G. pyloalis larvae treated with TFP compared to the control group by transcriptome sequencing. In total, 86,949,569 and 67,442,028 clean reads were obtained from TFP-treated and control G. pyloalis larvae, respectively. A total of 5588 differentially expressed genes (DEGs) were identified in TFP-treated and control G. pyloalis larvae, of which 3084 genes were upregulated and 2504 genes were downregulated. We analyzed the expression of 43 candidate detoxification enzyme genes associated with insecticide tolerance using qPCR. According to the spatiotemporal expression pattern of DEGs, we found that CYP6ABE1, CYP333A36 and GST-epsilon8 were highly expressed in the midgut, while CarEs14 was strongly expressed in haemolymph. Furthermore, we successfully knocked down these genes by RNA interference. After silencing CYP6ABE1 and CYP333A36, bioassay showed that the mortality rate of TFP-treated G. pyloalis larvae was significantly higher compared to the control group. This study provides a theoretical foundation for understanding the sensitivity of G. pyloalis to TFP and establish the basis for the effective and green management of this pest.


Assuntos
Inseticidas , Mariposas , Animais , Inseticidas/farmacologia , Inseticidas/metabolismo , Mariposas/metabolismo , Larva/genética , Pirazóis/metabolismo
5.
Plant J ; 106(3): 801-816, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33595139

RESUMO

Elucidating the biochemical and molecular basis of premature abscission in fruit crops should help develop strategies to enhance fruit set and yield. Here, we report that LcERF2 contributes to differential abscission rates and responses to ethylene in Litchi chinensis (litchi). Reduced LcERF2 expression in litchi was observed to reduce fruit abscission, concurrent with enhanced pedicel growth and increased levels of hexoses, particularly galactose, as well as pectin abundance in the cell wall. Ecoptic expression of LcERF2 in Arabidopsis thaliana caused enhanced petal abscission, together with retarded plant growth and reduced pedicel galactose and pectin contents. Transcriptome analysis indicated that LcERF2 modulates the expression of genes involved in cell wall modification. Yeast one-hybrid, dual-luciferase reporter and electrophoretic mobility shift assays all demonstrated that a UDP-glucose-4-epimerase gene (LcUGE) was the direct downstream target of LcERF2. This result was further supported by a significant reduction in the expression of the A. thaliana homolog AtUGE2-4 in response to LcERF2 overexpression. Significantly reduced pedicel diameter and enhanced litchi fruit abscission were observed in response to LcUGE silencing. We conclude that LcERF2 mediates fruit abscission by orchestrating cell wall metabolism, and thus pedicel growth, in part by repressing the expression of LcUGE.


Assuntos
Parede Celular/metabolismo , Frutas/metabolismo , Litchi/metabolismo , Proteínas de Plantas/metabolismo , UDPglucose 4-Epimerase/metabolismo , Arabidopsis , Ensaio de Desvio de Mobilidade Eletroforética , Frutas/enzimologia , Frutas/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Genes de Plantas/genética , Litchi/enzimologia , Litchi/crescimento & desenvolvimento , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , UDPglucose 4-Epimerase/genética
6.
J Psychiatry Neurosci ; 47(2): E153-E161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35477683

RESUMO

BACKGROUND: At present, the use of repetitive transcranial magnetic stimulation (rTMS) for generalized anxiety disorder (GAD) is limited to single-site interventions. We investigated whether dual-site frontoparietal stimulation delivered using cortical-cortical paired associative stimulation (ccPAS) had stronger clinical efficacy than single-site stimulation in patients with GAD. METHODS: We randomized 50 patients with GAD to 1 Hz rTMS (10 sessions) using 1 of the following protocols: single-site stimulation over the right dorsolateral prefrontal cortex (dlPFC; 1500 pulses per session); single-site stimulation over the right posterior parietal cortex (PPC; 1500 pulses per session); repetitive dual-site ccPAS (rds-ccPAS) over the right dlPFC and right PPC with 1500 pulses per session (rd-ccPAS-1500); or rds-ccPAS over the right dlPFC and right PPC with 750 pulses per session (rd-ccPAS-750). Both rds-ccPAS treatments used a between-site interval of 100 ms. RESULTS: Clinical scores for anxiety, depression and insomnia were reduced in all 4 groups after treatment. We found greater improvements in anxiety symptoms in the rds-ccPAS-1500 group compared to the rds-ccPAS-750 and single-site groups. We found greater improvements in depression symptoms and insomnia in the rds-PAS-1500 group compared to the single-site groups. The rds-ccPAS-1500 group also showed significant or trend-level improvements in anxiety symptoms and insomnia at 10-day and 1-month followup. More patients responded to treatment with rds-ccPAS-1500 than with single-site stimulation. The between-group differences in response rates persisted to the 3-month follow-up. Treatment using rds-ccPAS with a between-site interval of 100 ms induced a more significant improvement than the between-site interval of 50 ms we evaluated in a previous study. LIMITATIONS: These results need to be replicated in a larger sample using sham control and equal-pulse single-site stimulation. CONCLUSION: Frontoparietal rds-ccPAS may be a better treatment option for GAD.


Assuntos
Transtornos de Ansiedade , Estimulação Magnética Transcraniana , Transtornos de Ansiedade/terapia , Humanos , Lobo Parietal/fisiologia , Projetos Piloto , Distúrbios do Início e da Manutenção do Sono , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
7.
Physiol Plant ; 174(6): e13840, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36512339

RESUMO

Plant volatile organic compounds are the most abundant and structurally diverse plant secondary metabolites. They play a key role in plant lifespan via direct and indirect plant defenses, attracting pollinators, and mediating various interactions between plants and their environment. The ecological diversity and context-dependence of plant-plant communication driven by volatiles are crucial elements that influence plant performance in different habitats. Plant volatiles are also valued for their multiple applications in food, flavor, pharmaceutical, and cosmetics industries. In the current review, we summarize recent advances that have elucidated the functions of plant volatile organic compounds as mediators of plant interaction at community and individual levels, highlighting the complexities of plant receiver feedback to various signals and cues. This review emphasizes volatile terpenoids, the most abundant class of plant volatile organic compounds, highlighting their role in plant adaptability to global climate change and stress-response pathways that are integral to plant growth and survival. Finally, we identify research gaps and suggest future research directions.


Assuntos
Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/metabolismo , Mudança Climática , Plantas/metabolismo , Aclimatação
8.
Physiol Plant ; 174(6): e13796, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36251666

RESUMO

Volatile organic compounds (VOCs) are essential traits of flowers since they attract pollinators, aid in seed distribution, protect the plant from internal and external stimuli, and are involved in plant-plant and plant-environment interactions. Apart from their role in plants, VOCs are used in pharmaceuticals, fragrances, cosmetics, and flavorings. Litchi (Litchi chinensis Sonn.) is a popular fruit due to its enticing red appearance, exotic taste, and high nutritional qualities. Litchi flowers bloom as inflorescences primarily on the shoot terminals. There are three distinct flower types, two male and one female, all of which are produced on the same panicle and rely on insect pollination. Herein, we used a comprehensive metabolomic approach to examine the volatile profile of litchi fruit (green pericarp, yellow pericarp, and red pericarp) as well as male and female flowers (bud stage, half open and full bloom). From a quantitative examination of the volatiles in L. chinensis, a total of 19, 22, and 21 VOCs were discovered from female flowers, male flowers, and fruits, with the majority of them belonging to sesquiterpenes. Multivariate analysis revealed that the volatile profiles of fruits differ from those of male and female flowers. Three VOCs were unique to male flowers and ten to the fruit, while eight VOCs were shared by both male and female flowers and eleven by both male and female flowers and the fruit. Furthermore, for the first time, we identified and comprehensively studied the TERPENE SYNTHASE genes (TPS) using the litchi genome and transcriptome database, which revealed 38 TPS genes unevenly distributed across the 15 chromosomes. A phylogenetic study showed that LcTPS were grouped into TPS-b, TPS-c, TPS-e, TPS-f, and TPS-g subfamilies, with TPS-b having the most genes. The conserved motifs (RRX8 W, NSE/DTE, and DDXX D) were studied in LcTPSs, and significant variation between subfamilies was discovered. Furthermore, after integrating the metabolome and transcriptome datasets, several VOCs were shown to be development-specific and highly linked with distinct LcTPS genes, making them promising biomarkers. Interestingly, LcTPS17/20/23/24/31 were associated with monoterpene edges, while the rest were connected to sesquiterpene edges, indicating their probable participation in the aroma biosynthesis mechanism of certain compounds.


Assuntos
Litchi , Sesquiterpenos , Litchi/genética , Odorantes , Filogenia , Perfilação da Expressão Gênica , Transcriptoma/genética , Metaboloma/genética
9.
BMC Pregnancy Childbirth ; 22(1): 110, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35144595

RESUMO

BACKGROUND: Bilateral simultaneous fallopian tubal pregnancy is one of the rarest forms of ectopic pregnancy. Due to the lack of unique features and clinical presentation to distinguish bilateral from unilateral ectopic pregnancy, challenges the diagnosis. CASE REPORT: A 27-year-old Asian woman presented with pelvic pain and vaginal bleeding. Pelvic transvaginal ultrasound showed fluid in Douglas Pouch and posterior fornix puncture revealed unclotted blood. Laparoscopic examination unveiled bilateral ectopic pregnancy with two corpus luteum visible in the right ovary, suggesting a double spontaneous unilateral ovulation. Bilateral fallopian tube fenestration and embryo extraction were performed to preserve fertility. CONCLUSION: Diagnosis of bilateral tubal pregnancy is difficult during preoperative ultrasound examination and careful examination during laparoscopic inspection of the whole pelvic cavity to avoid missed diagnosis.


Assuntos
Corpo Lúteo/diagnóstico por imagem , Tubas Uterinas/cirurgia , Ovulação , Gravidez Tubária/diagnóstico , Gravidez Tubária/patologia , Gravidez Tubária/cirurgia , Adulto , Feminino , Humanos , Laparoscopia/métodos , Gravidez , Doenças Raras/diagnóstico , Doenças Raras/patologia , Doenças Raras/cirurgia , Resultado do Tratamento
10.
Eur Neurol ; 85(6): 437-445, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35896086

RESUMO

INTRODUCTION: Anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis is clinically heterogeneous, especially at presentation, and though it is sometimes found in association with tumor, this is by no means the rule. METHODS: Clinical data for 10 patients with anti-LGI1 encephalitis were collected including one case with teratoma and nine cases without and compared for clinical characteristics. Microscopic pathological examination and immunohistochemical assay of the LGI1 antibody were performed on teratoma tissue obtained by laparoscopic oophorocystectomy. RESULTS: In our teratoma-associated anti-LGI1 encephalitis case, teratoma pathology was characterized by mostly thyroid tissue and immunohistochemical assay confirmed positive nuclear staining of LGI1 in some tumor cells. The anti-LGl1 patient with teratoma was similar to the non-teratoma cases in many ways: age at onset (average 47.3 in non-teratoma cases); percent presenting with rapidly progressive dementia (67% of non-teratoma cases) and psychiatric symptoms (33%); hyponatremia (78%); normal cerebrospinal fluid results except for positive LGI1 antibody (78%); bilateral hippocampal hyperintensity on magnetic resonance imaging (44%); diffuse slow waves on electroencephalography (33%); good response to immunotherapy (67%); and mild residual cognitive deficit (22%). Her chronic anxiety and presentation with status epilepticus were the biggest differences compared with the non-teratoma cases. CONCLUSION: In our series, anti-LGI1 encephalitis included common clinical features in our series: rapidly progressive dementia, faciobrachial dystonic seizures, behavioral disorders, hyponatremia, hippocampal hyperintensity on magnetic resonance imaging, and residual cognitive deficit. We observed some differences (chronic anxiety and status epilepticus) in our case with teratoma, but a larger accumulation of cases is needed to improve our knowledge base.


Assuntos
Demência , Encefalite , Glioma , Hiponatremia , Encefalite Límbica , Estado Epiléptico , Feminino , Humanos , Encefalite Límbica/diagnóstico por imagem , Encefalite Límbica/complicações , Hiponatremia/complicações , Leucina/uso terapêutico , Autoanticorpos , Peptídeos e Proteínas de Sinalização Intracelular/uso terapêutico , Encefalite/complicações , Neuroimagem , Glioma/complicações , Estado Epiléptico/complicações
11.
J Exp Biol ; 224(9)2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795419

RESUMO

Hauser's engraver beetle, Ips hauseri, is a serious pest in spruce forest ecosystems in Central Asia. Its monoterpenoid signal production, transcriptome responses and potential regulatory mechanisms remain poorly understood. The quality and quantity of volatile metabolites in hindgut extracts of I. hauseri were found to differ between males and females and among three groups: beetles that were newly emerged, those with a topical application of juvenile hormone III (JHIII) and those that had been feeding for 24 h. Feeding males definitively dominated monoterpenoid signal production in I. hauseri, which uses (4S)-(-)-ipsenol and (S)-(-)-cis-verbenol to implement reproductive segregation from Ipstypographus and Ipsshangrila. Feeding stimulation induced higher expression of most genes related to the biosynthesis of (4S)-(-)-ipsenol than JHIII induction, and showed a male-specific mode in I. hauseri. JHIII stimulated males to produce large amounts of (-)-verbenone and also upregulated the expression of several CYP6 genes, to a greater extent in males than in females. The expression of genes involved in the metabolism of JHIII in females and males was also found to be upregulated. Our results indicate that a species-specific aggregation pheromone system for I. hauseri, consisting of (4S)-(-)-ipsenol and S-(-)-cis-verbenol, can be used to monitor population dynamics or mass trap killing. Our results also enable a better understanding of the bottom-up role of feeding behaviors in mediating population reproduction/aggregation and interspecific interactions.


Assuntos
Besouros , Animais , Besouros/genética , Ecossistema , Feminino , Hormônios Juvenis , Masculino , Monoterpenos , Feromônios , Casca de Planta
12.
Inorg Chem ; 60(3): 1480-1490, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33427451

RESUMO

Graphene materials with particular properties are proved to be beneficial to photoelectric devices, but there are rare reports on a positive effect by graphene on emissive layer materials of organic light-emitting diodes (OLEDs) previously. On the basis of the latest important experiments, an OLED device with the aid of graphene quantum dots shows the dawn of their application for luminescent materials. The luminescence performance has been improved, but the understanding of the internal excited-state radiation mechanism of the material needs further study. In this work, the Pt(II)-coordinated graphene quantum dot coplanar structures with different shapes are studied theoretically in detail, and the results present the improvement in phosphorescence under the promoted radiative decay and suppressed nonradiative decay. This composite combines the advantages of transition metal complexes and graphene quantum dots and also exhibits excellent properties in the light absorption region and carrier transportation for the OLED. This comprehensive theoretical calculation research can provide a comprehensive basis of the material design in the future.

13.
BMC Vet Res ; 17(1): 213, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107958

RESUMO

BACKGROUND: Enterocytozoon bieneusi, a microsporidian species, is a zoonotic pathogen found in both humans and animals. Here, we determined the prevalence, explored the different genotypes of E. bieneusi in wild rhesus macaques (Macaca mulatta) (Hainan Island of China), and assessed their zoonotic potential. METHODS: We collected 173 fecal specimens from wild rhesus macaques living in Nanwan Monkey Island, Hainan, China. Subsequently, we identified and genotyped E. bieneusi using nested PCR analysis amplification of the internal transcribed spacer region (ITS) of the rRNA gene. Lastly, a neighbor-joining tree was built based on gene sequences from the ITS region of E. bieneusi. RESULTS: Of the 173 specimens from wild rhesus macaques, 26 (15%) were infected with E. bieneusi. We identified six genotypes of E. bieneusi, of which five were known: PigEBITS7 (n = 20), D (n = 2), Type IV (n = 1), Peru6 (n = 1), Henan-III (n = 1), and a novel genotype: HNM-IX (n = 1). From the phylogenetic analysis, the six genotypes identified here were all clustered into zoonotic group 1. CONCLUSION: This study is the first report to detect E. bieneusi infection in wild rhesus macaques from Hainan, China. Human-pathogenic genotypes D, Henan-III, Peru6, PigEbITS7, and Type IV in the wild rhesus macaques support these animals infected with E. bieneusi have a public health significance.


Assuntos
Enterocytozoon/genética , Macaca mulatta/virologia , Microsporidiose/veterinária , Doenças dos Macacos/virologia , Animais , Animais Selvagens , China/epidemiologia , Enterocytozoon/isolamento & purificação , Feminino , Genoma Viral , Genótipo , Humanos , Incidência , Masculino , Microsporidiose/epidemiologia , Microsporidiose/virologia , Doenças dos Macacos/epidemiologia , Filogenia , Prevalência , Saúde Pública , Zoonoses/virologia
14.
BMC Plant Biol ; 19(1): 62, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30732564

RESUMO

BACKGROUND: Maturation of litchi (Litchi chinensis) fruit is characterized by dramatic changes in pigments in the pericarp and flavor compounds in the aril. Among them, the biosynthesis of anthocyanins is most noticeable. Previous studies showed that LcMYB1 and LcbHLH transcription factors participated in regulating the anthocyanin biosynthesis in litchi. However, the roles of other MYB factors remain unclear. RESULTS: In this study, we cloned and characterized the function of LcMYB5, a novel R2R3-MYB identified from litchi transcriptome. Although LcMYB5 was constitutively expressed in litchi tissues and its expressions was not correlated with tissue coloration, overexpression of LcMYB5 resulted in enhanced biosynthesis of anthocyanins in tobacco and petunia concurrent with the up-regulation of their endogenous bHLHs and key structural genes in anthocyanin precursor biosynthesis. These results indicate that LcMYB5 is an R2R3 transcriptional factor regulates anthocyanin biosynthesis either by directly activating the expression of key structural genes such as DFR or by indirectly up regulating the expressions of endogenous bHLH regulators. More interestingly, the pH values in petals and leaves from transgenic lines were significant lower than those in both untransformed tobacco and petunia, indicating LcMYB5 is also associated with pH regulation. The expressions of LcMYB5 and its bHLH partner LcbHLH1 were consistent with the expression of putative tissue acidification gene LcPH1, and the changes in malic acid provided further evidence for the close relationship between LcMYB5 and tissue acidification. CONCLUSIONS: Taking together, our study indicated that LcMYB5 is involved in not only anthocyanin biosynthesis but also tissue acidification.


Assuntos
Antocianinas/metabolismo , Litchi/metabolismo , Fatores de Transcrição/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Litchi/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética
15.
Immunol Invest ; 48(2): 169-180, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30273064

RESUMO

BACKGROUND: We carried out a meta-analysis to assess whether Toll-like receptor 2 (TLR2) rs5743708 and Toll-like receptor 4 (TLR4) rs4986790 polymorphisms are associated with the risk of atopic dermatitis. METHODS: A systematic search of PubMed, Embase, and Web of Science was performed to identify eligible case-control studies on the association of rs5743708 and rs4986790 with the risk of atopic dermatitis. Statistical analyses of the odds ratio (OR), 95% confidence interval (CI), and p value were performed using STATA software. RESULTS: Our meta-analysis included a total of nine case-control studies, all involving Caucasian populations. With respect to the TLR2 rs5743708 G/A polymorphism, there was a statistically significant difference in the overall risk of atopic dermatitis between the case and control groups [OR = 2.07, p value of association test, p(association) = 0.001 in allele (A vs. G) model; OR = 1.93, p(association) = 0.004 in carrier (A vs. G) model; OR = 2.07, p(association) = 0.001 in heterozygote (GA vs. GG) model; OR = 1.99, p(association) = 0.001 in dominant (GA+ AA vs. GG) model]. Similar positive results were observed in the subgroup analysis of "population-based control." For the TLR4 rs4986790 A/G polymorphism, an increased atopic dermatitis risk was detected in the case group under the allele [OR = 1.78, p(association) = 0.013], carrier [OR = 1.69, p(association) = 0.027] and heterozygote [OR = 1.74, p(association) = 0.020] models, but not the dominant [OR = 1.44, p(association) = 0.070] model, in comparison to the population-based control group. CONCLUSION: Our meta-analysis revealed a novel finding that the heterogeneous "GA" genotype of the TLR2 rs5743708 and "AG" genotype of the TLR4 rs4986790 may be associated with increased susceptibility to atopic dermatitis in Caucasians.


Assuntos
Alelos , Dermatite Atópica/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Estudos de Casos e Controles , Dermatite Atópica/diagnóstico , Frequência do Gene , Estudos de Associação Genética/métodos , Genótipo , Humanos , Razão de Chances , Viés de Publicação , Medição de Risco
16.
J Exp Bot ; 69(7): 1649-1661, 2018 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-29281092

RESUMO

Although methylated cyclitols constitute a major proportion of the carbohydrates in many plant species, their physiological roles and biosynthetic pathway are largely unknown. Quebrachitol (2-O-methyl-chiro-inositol) is one of the major methylated cyclitols in some plant species. In litchi, quebrachitol represents approximately 50% of soluble sugars in mature leaves and 40% of the total sugars in phloem exudate. In the present study, we identified bornesitol as a transient methylated intermediate of quebrachitol and measured the concentrations of methyl-inositols in different tissues and in tissues subjected to different treatments. 14CO2 feeding and phloem exudate experiments demonstrated that quebrachitol is one of the transportable photosynthates. In contrast to other plant species, the biosynthesis of quebrachitol in litchi is not associated with osmotic stress. High quebrachitol concentrations in tissues of the woody plant litchi might represent a unique carbon metabolic strategy that maintains osmolality under reduced-sucrose conditions. The presence of bornesitol but not ononitol in the leaves indicates a different biosynthetic pathway with pinitol. The biosynthesis of quebrachitol involves the methylation of myo-inositol and the subsequent epimerization of bornesitol. An inositol methyltransferase gene (LcIMT1) responsible for bornesitol biosynthesis was isolated and characterized for the first time, and the biosynthesis pathways of methyl-inositols are discussed.


Assuntos
Inositol/análogos & derivados , Litchi/metabolismo , Floema/fisiologia , Transporte Biológico , Inositol/biossíntese , Litchi/química , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Pressão Osmótica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
17.
Opt Lett ; 43(9): 2030-2033, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29714738

RESUMO

Quantum key distribution (QKD) provides an attractive solution for secure communication. However, channel disturbance severely limits its application when a QKD system is transferred from the laboratory to the field. Here a high-speed Faraday-Sagnac-Michelson QKD system is proposed that can automatically compensate for the channel polarization disturbance, which largely avoids the intermittency limitations of environment mutation. Over a 50 km fiber channel with 30 Hz polarization scrambling, the practicality of this phase-coding QKD system was characterized with an interference fringe visibility of 99.35% over 24 h and a stable secure key rate of 306 k bits/s over seven days without active polarization alignment.

19.
Artigo em Zh | MEDLINE | ID: mdl-30133242

RESUMO

Objective: To clone and express the galectin-1 gene of Angiostrongylus cantonensis, and test the agglutination property of its protein. Methods: The three-dimensional structure of galectin-1 was analyzed with Swiss Model. Total RNA was extracted from male worms of A. cantonensis. Primers were designed for galectin-1 based on its coding region (GenBank Accession No. JN133961.1). RT-PCR was performed, and the PCR products were subcloned to pCold Ⅲ plasmid and transduced into Escherichia coli BL21 strain. The recombinant plasmid was extracted from positive clones on LB plate containing 100 µg/ml Kanamycin, and validated with double digestion, PCR identification and sequencing. The confirmed positive clones of E. coli BL21 with the recombinant plasmid were grown in LB medium containing ampicillin (100 µg/ml, 100 µl). IPTG was added to induce expression of the plasmid. The galectin-1 recombinant protein was purified with Ni-NTA beads, and analyzed with SDS-PAGE and Western blotting using anti-serum of mouse immunized with whole worms of A. cantonensis. The agglutination reaction with red blood cells in fresh blood of ICR mouse was observed for the 10-fold serial dilutions of recombinant proteins (5.55 × 10(-1)-5.55 × 10(-5) ng/µl). Results: The Swiss Model analysis showed that the functional galectin-1 had a non-dimeric form. As was expected, the RT-PCR products had a size of 850 bp. Results of double digestion, PCR and sequencing showed successful construction of the pCold Ⅲ-galectin-1 plasmid. SDS-PAGE revealed expression of soluble recombinant fusion protein with molecular weight of ~36 000. Western blotting showed that the galectin-1 protein was recognized by mouse anti-serum. In addition, the minimun concentration of galectin-1 that showed significant agglutination reactions with mouse red blood cells was 5.55 × 10(-4) ng/µl. Conclusion: The galectin-1 clone can be expressed in the pCold Ⅲ plasmid, and its protein product has agglutination property.


Assuntos
Angiostrongylus cantonensis , Clonagem Molecular , Aglutinação , Animais , Western Blotting , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Galectina 1 , Expressão Gênica , Camundongos , Camundongos Endogâmicos ICR , Plasmídeos , Reação em Cadeia da Polimerase , Proteínas Recombinantes
20.
Physiol Plant ; 156(2): 139-149, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26419221

RESUMO

Anthocyanins generate the red color in the pericarp of Litchi chinensis. UDP-glucose: flavonoid 3-O-glycosyltransferase (UFGT, EC. 2.4.1.91) stabilizes anthocyanidin by attaching sugar moieties to the anthocyanin aglycone. In this study, the function of an UFGT gene involved in the biosynthesis of anthocyanin was verified through heterologous expression and virus-induced gene silencing assays. A strong positive correlation between UFGT activity and anthocyanin accumulation capacity was observed in the pericarp of 15 cultivars. Four putative flavonoid 3-O-glycosyltransferase-like genes, designated as LcUFGT1 to LcUFGT4, were identified in the pericarp of litchi. Among the four UFGT gene members, only LcUFGT1 can use cyanidin as its substrate. The expression of LcUFGT1 was parallel with developmental anthocyanin accumulation, and the heterologously expressed protein of LcUFGT1 displayed catalytic activities in the formation of anthocyanin. The LcUFGT1 over-expression tobacco had darker petals and pigmented filaments and calyxes resulting from higher anthocyanin accumulations compared with non-transformed tobacco. In the pericarp with LcUFGT1 suppressed by virus-induced gene silencing, pigmentation was retarded, which was well correlated with the reduced-LcUFGT1 transcriptional activity. These results suggested that the glycosylation-related gene LcUFGT1 plays a critical role in red color formation in the pericarp of litchi.

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