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1.
Nanoscale ; 15(12): 5720-5725, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36880574

RESUMO

Perovskite nanocrystals have attracted much attention due to their unique optical and electronic properties. Much progress has also been made in the development of light-emitting diodes based on perovskite nanocrystals in the past years. However, compared with the widely reported opaque perovskite nanocrystal light-emitting diodes, semitransparent perovskite nanocrystal light-emitting diodes are rarely studied, which affects the potential application of perovskite nanocrystals in the translucent display field in the future. Here, poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN), a conjugated polymer, was used as an electron transport layer to fabricate the inverted opaque and semitransparent perovskite light-emitting diodes. The maximum external quantum efficiency and luminance were improved from 0.13% and 1041 cd m-2 to 2.07% and 12 540 cd m-2, respectively, through device optimization in opaque light-emitting diodes. The corresponding semitransparent device also demonstrated high transmittance (average 61% from 380 to 780 nm) and high brightness of 1619 and 1643 cd m-2 for the bottom and top sides, respectively.

2.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675108

RESUMO

In China, nitrogen (N) fertilizer is excessively used in sugarcane planting areas, while the nitrogen use efficiency (NUE) of sugarcane is relatively low. Mining and identifying the key genes in response to low N stress in sugarcane can provide useful gene elements and a theoretical basis for developing sugarcane varieties with high NUE. In our study, RNA-Seq combined with qRT-PCR analysis revealed that the ScAMT1.1 gene responded positively to low N stress, resulting in the stronger low N tolerance and high NUE ability of sugarcane cultivar ROC22. Then, ScAMT1.1 was cloned from sugarcane. The full-length cDNA of the ScAMT1.1 gene is 1868 bp, containing a 1491 bp open reading frame (ORF), and encoding 496 amino acids. ScAMT1.1 belongs to the AMT superfamily and shares 91.57% homologies with AMT1.1 from Oryza sativa. Furthermore, it was stably overexpressed in rice (O. sativa). Under low N treatment, the plant height and the fresh weight of the ScAMT1.1-overexpressed transgenic rice were 36.48% and 51.55% higher than that of the wild-type, respectively. Both the activity of ammonium assimilation key enzymes GS and GDH, and the expression level of ammonium assimilation key genes, including GS1.1, GS1.2, GDH, Fd-GOGAT, and NADH-GOGAT2 in the transgenic plants, were significantly higher than that of the wild-type. The grain number and grain yield per plant in the transgenic rice were 6.44% and 9.52% higher than that of the wild-type in the pot experiments, respectively. Taken together, the sugarcane ScAMT1.1 gene has the potential to improve ammonium assimilation ability and the yield of transgenic rice under low N fertilizer conditions. This study provided an important functional gene for improving sugarcane varieties with high NUE.


Assuntos
Compostos de Amônio , Oryza , Saccharum , Nitrogênio/metabolismo , Compostos de Amônio/metabolismo , Oryza/metabolismo , Saccharum/genética , Saccharum/metabolismo , Expressão Ectópica do Gene , Fertilizantes , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas
3.
Int J Biol Macromol ; 224: 1-19, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481328

RESUMO

Wall-associated kinase (WAK) is widely involved in signal transduction, reproductive growth, responses to pathogen infection and metal ion stress in plants. In this study, 19, 12, and 37 SsWAK genes were identified in Saccharum spontaneum, Saccharum hybrid and Sorghum bicolor, respectively. Phylogenetic tree showed that they could be divided into three groups. These WAK genes contained multiple cis-acting elements related to stress, growth and hormone response. RNA-seq analysis demonstrated that SsWAK genes were constitutively expressed in different sugarcane tissues and involved in response to smut pathogen (Sporisorium scitamineum) stress. Additionally, ScWAK1 (GenBank Accession No. OP479864), was then isolated from sugarcane cultivar ROC22. It was highly expressed in leaves and roots and its expression could be induced under SA and MeJA stress. Besides, ScWAK1 was significantly downregulated in both smut-resistant and susceptible sugarcane cultivars in response to S. scitamineum infection. ScWAK1 was a membrane protein without self-activating activity. Furthermore, transient expression of ScWAK1 in Nicotiana benthamiana enhanced the susceptibility of tobacco to the inoculation of Ralstonia solanacearum and Fusarium solani var. coeruleum, suggesting its negative role in disease resistance. The present study reveals the origin, distribution and evolution of WAK gene family and provides potential gene resources for sugarcane molecular breeding.


Assuntos
Saccharum , Ustilaginales , Saccharum/metabolismo , Filogenia , Resistência à Doença/genética , Ustilaginales/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Doenças das Plantas/genética
4.
J Formos Med Assoc ; 122(7): 603-611, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36336606

RESUMO

OBJECTIVE: The aim of this study was to determine whether cognitive function is associated with future falls in older patients with diabetes mellitus (DM) compared with those without DM. Cognitive function was divided into several domains to further analyze. METHODS: A total of 678 individuals met the inclusion criteria and comprised the final study population. The mean age was 74.35 ± 5.35 years, and 58.9% of the participants were female (n = 400). At the baseline, cognitive function was measured by the Mini Mental State Examination (MMSE), and DM diagnoses were determined by medical records. The self-reported any falls data were obtained via face-to-face questioning at the 1-year follow-up. RESULTS: At baseline, 15.6% of participants (n = 106) were diagnosed with DM. According to whether they had any falls during 1-year follow-up, there was a significant difference between the two group in fasting plasma glucose (p = 0.012) and DM (p = 0.036) at baseline. Among the older adults with DM, those who had experienced any falls had poorer cognitive function (p = 0.014). After adjusting for various covariates, we found that MMSE (95% CI 0.790-0.991, p = 0.034), orientation to place (95% CI 0.307-0.911, p = 0.022) and registration (95% CI 0.162-0.768, p = 0.009) were significantly associated with falls in the follow-up. CONCLUSION: Our study found that in patients with DM, cognitive function is related to future falls. Not only overall cognitive function, but also orientation to place and registration were all associated with future falls in older adults with DM. When completing the fall risk assessment of elderly patients with DM, clinicians should give more attention to the testing of cognitive function.


Assuntos
Diabetes Mellitus , Vida Independente , Idoso , Feminino , Humanos , Masculino , Acidentes por Quedas , Cognição , Diabetes Mellitus/epidemiologia , População do Leste Asiático
5.
Genes Genomics ; 45(1): 103-122, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35608775

RESUMO

BACKGROUND: Calmodulin (CaM) plays an essential role in binding calcium ions and mediating the interpretation of Ca2+ signals in plants under various stresses. However, the evolutionary relationship of CaM family proteins in Saccharum has not been elucidated. OBJECTIVE: To deduce and explore the evolution and function of Saccharum CaM family. METHODS: A total of 104 typical CaMs were obtained from Saccharum spontaneum and other 18 plant species. The molecular characteristics and evolution of those CaM proteins were analyzed. A typical CaM gene, ScCaM1, was subsequently cloned from sugarcane (Saccharum spp. hybrid). Its expression patterns in different tissues and under various abiotic stresses were assessed by quantitative real-time PCR. Then the green fluorescent protein was used to determine the subcellular localization of ScCaM1. Finally, the function of ScCaM1 was evaluated via heterologous yeast expression systems. RESULTS: Three typical CaM members (SsCaM1, SsCaM2, and SsCaM3) were identified from the S. spontaneum genome database. CaMs were originated from the two last common ancestors before the origin of angiosperms. The number of CaM family members did not correlate to the genome size but correlated with allopolyploidization events. The ScCaM1 was more highly expressed in buds and roots than in other tissues. The expression patterns of ScCaM1 suggested that it was involved in responses to various abiotic stresses in sugarcane via different hormonal signaling pathways. Noteworthily, its expression levels appeared relatively stable during the cold exposure in the cold-tolerant variety but significantly suppressed in the cold-susceptible variety. Moreover, the recombinant yeast (Pichia pastoris) overexpressing ScCaM1 grew better than the wild-type yeast strain under cold and oxidative stresses. It was revealed that the ScCaM1 played a positive role in reactive oxygen species scavenging and conferred enhanced cold and oxidative stress tolerance to cells. CONCLUSION: This study provided comprehensive information on the CaM gene family in Saccharum and would facilitate further investigation of their functional characterization.


Assuntos
Saccharum , Calmodulina/genética , Oxidantes/metabolismo , Saccharum/genética , Saccharum/metabolismo
6.
Insects ; 13(11)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36421955

RESUMO

The Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), is a destructive wheat pest worldwide and an important alien species in China. Based on 258 distribution records and nine environmental factors of the Hessian fly, we predicted the potential distribution area in China under three current and future (2050s and 2070s) climate change scenarios (RCP2.6, RCP4.5, and RCP8.5) via the optimized MaxEnt model. Under the current climate conditions, the suitable distribution areas of the Hessian fly in China were 25-48° N, 81-123° E, and the total highly suitable distribution area is approximately 9.63 × 105 km2, accounting for 9.99% of the total national area. The highly suitable areas are mainly located in northern Xinjiang and central and eastern China. With the rising global temperatures, except for the high-suitable areas under the RCP8.5 scenario, most potential geographic distribution areas would expand in the future. The minimum temperature in February (tmin-2), precipitation in March (prec-3), maximum temperature in November (tmax-11), and precipitation seasonality (bio-15) are important factors that affect the potential geographic distribution of the Hessian fly. This study provides an important reference and empirical basis for management of the Hessian fly in the future.

7.
Int J Mol Sci ; 23(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36361975

RESUMO

Chemical nitrogen (N) fertilizer is widely used in sugarcane production, especially in China and India. Understanding the molecular mechanisms and mining miRNAs and their target genes associated with nitrogen use efficiency (NUE) in sugarcane can aid in developing the N-efficient varieties, and thus is beneficial to reduce N fertilizer application. In this study, the root miRNA database of N-efficient sugarcane variety ROC22 under low N stress (0.3 mM NH4NO3) for 3 h was constructed, along with their transcriptome-rearranged data. KEGG analysis indicated that those candidate target genes, corresponding to differentially expressed miRNAs, were mainly enriched in N metabolism, amino acid metabolism, carbohydrate metabolism, photosynthesis, and hormone signal transduction pathways. It was found that under low N stress for 0-24 h, there was a negative correlation between miR168 and SPX, along with miR396 and acnA. Furthermore, the expression of miR156 in the roots of ROC22 was significantly up-regulated under low N treatment. Compared with the wild-type, the Arabidopsis plants overexpressing sugarcane miR156 exhibited significantly improved length and surface area of roots, while the expression of one NO3- transporter gene NRT1.1, three N assimilation key genes (NR1, NIR1, and GS), and the activity of two N assimilation key enzymes (NR and GS) were up-regulated under low N treatment. It can be reasonably deduced that sugarcane miR156 can enhance the nitrogen assimilation ability of the overexpressed Arabidopsis plants under low N application, and thus has a potential ability for improving sugarcane NUE. The present study should be helpful for understanding the molecular regulatory network in the N-efficient sugarcane genotype responding to low N stress and could provide the candidate miRNAs with a potential function in improving sugarcane NUE.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , MicroRNAs , Saccharum , Saccharum/genética , Saccharum/metabolismo , Nitrogênio/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação da Expressão Gênica de Plantas , Arabidopsis/genética , Fertilizantes , Plantas Geneticamente Modificadas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Transporte de Ânions/metabolismo , Nitrito Redutases/metabolismo , Proteínas de Arabidopsis/genética
8.
Int J Mol Sci ; 23(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36076957

RESUMO

The dehydration-responsive element-binding protein (DREB) is a subgroup member of the AP2/ERF family and actively participates in the response of plants to abiotic stress. Although DREB genes have been studied in a variety of plant species, there are few reports of DREB genes in sugarcane (Saccharum spp.). In this study, a novel full-length cDNA sequence of the ScDREB2B-1 gene was cloned from the Saccharum hybrid ROC22, whose encoding protein contained only one AP2-conserved domain and was clustered into the DREB (A-2) subgroup. The diverse promoter elements in the ScDREB2B-1 gene and the accumulated transcripts of its homologous gene (SsAP2/ERF-107) in S. spontaneum under drought stress suggest that the ScDREB2B-1 gene may play a role in drought response. In addition, reverse transcription quantitative PCR analysis showed that the expression level of the ScDREB2B-1 gene was upregulated in the root and leaf of ROC22 under polyethylene glycol, sodium chloride and abscisic acid (ABA) treatments. The yeast two-hybrid experiment demonstrated that ScDREB2B-1 had transcriptional self-activation activity. Compared with wild-type plants, the overexpression of the ScDREB2B-1 gene improved the drought tolerance of the transgenic Nicotiana benthamiana by activating the ABA pathway to enhance the expression of the ABA-responsive gene (NbNCED) and ABA content, regulate the intracellular reactive oxygen species (ROS) level (enhance the transcripts of ROS synthase-related gene NbRbohB and the activities of catalase, peroxidase and superoxide dismutase) and increase the relative water content, proline content and expression level of osmotic stress-related genes (NbERD and NbLEA). Collectively, our data indicate that ScDREB2B-1 is a stress-inducible and ABA-responsive transcription factor gene that responds to drought stress by regulating ABA signaling, ROS levels and stress-related gene expression. This study contributes to a better understanding of the biological function of ScDREB2B-1, which could serve as a foundation for future resistance breeding in sugarcane.


Assuntos
Secas , Saccharum , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Saccharum/genética , Saccharum/metabolismo , Estresse Fisiológico/genética , Nicotiana/metabolismo
10.
Biophys J ; 121(8): 1493-1501, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35276132

RESUMO

The DNA damage response is a highly orchestrated process. The involvement of the DNA damage response factors in DNA damage response depends on their biochemical reactions with each other and with chromatin. Using online live-cell imaging combined with heavy ion microbeam irradiation, we studied the response of the scaffold protein X-ray repair cross-complementary protein 1 (XRCC1) at the localized DNA damage in charged particle irradiated HT1080 cells expressing XRCC1-tagged RFP. The results showed that XRCC1 was recruited to the DNA damage with ultrafast kinetics in a poly ADP-ribose polymerase-dependent manner. The consecutive reaction model well explained the response of XRCC1 at ion hits, and we found that the XRCC1 recruitment was faster and dissociation was slower in the G2 phase than those in the G1 phase. The fractionated irradiation of the same cells resulted in accelerated dissociation at the previous damage sites, and the dissociated XRCC1 immediately recycled with a higher recruitment efficiency. Our data revealed XRCC1's new rescue mechanism and its high turnover in DNA damage response, which benefits our understanding of the biochemical mechanism in DNA damage response.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA , Dano ao DNA , Proteínas de Ligação a DNA/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Raios X , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/metabolismo
11.
Nano Lett ; 21(6): 2390-2396, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33683892

RESUMO

In this work, we demonstrate a process having the capability to realize single-digit nanometer lithography using single heavy ions. By adopting 2.15 GeV 86Kr26+ ions as the exposure source and hydrogen silsesquioxane (HSQ) as a negative-tone inorganic resist, ultrahigh-aspect-ratio nanofilaments with sub-5 nm feature size, following the trajectory of single heavy ions, were reliably obtained. Control experiments and simulation analysis indicate that the high-resolution capabilities of both HSQ resist and the heavy ions contribute the sub-5 nm fabrication result. Our work on the one hand provides a robust evidence that single heavy ions have the potential for single-digit nanometer lithography and on the other hand proves the capability of inorganic resists for reliable sub-5 nm patterning. Along with the further development of heavy-ion technology, their ultimate patterning resolution is supposed to be more accessible for device prototyping and resist evaluation at the single-digit nanometer scale.

12.
DNA Repair (Amst) ; 96: 102974, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32998084

RESUMO

The dynamic structure of nuclear chromatin and its regulation in the formation of repair complex is essential in DNA damage response and repair. Using single molecule localization microscopy STORM this work discovered that the nuclear chromatin organization was relaxed from 200 to 400 nm thick irregular frame and remodeled to dispersed sub-100 nm structure in HeLa cells after X-ray irradiation. The DSB repair factors (γ-H2AX, MDC1, 53BP1) showed distribution as microscale-colocalized and nanoscale interlaced substructure in the DSB repair complex. The dual-color nanoscopic imaging of γ-H2AX and chromatin at the DSB sites suggest that DNA damage response and repair cascade are chromatin structure-dependent and also partly dependent on the distance to the DSB sites. The sub-100 nm structure of fibers and nanoclusters of the relaxed nuclear chromatin and the DSB repair factors highly resembled the cross-section view of chromatin organization. These data demonstrated the polymorphic and dynamic behavior of the chromatin organization in vivo, and provided nanoscale insight into the interplay between chromatin remodeling and DNA damage response and DNA repair.


Assuntos
Montagem e Desmontagem da Cromatina , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Imagem Individual de Molécula , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Cromatina/metabolismo , Cromatina/efeitos da radiação , DNA/metabolismo , DNA/efeitos da radiação , Células HeLa , Histonas/metabolismo , Humanos , Radiação Ionizante , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
13.
ACS Appl Mater Interfaces ; 11(41): 38055-38060, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31553570

RESUMO

Rectified ion transport in nanochannels is the basis of ion channels in biological cells and has inspired emerging nanochannel applications in ion separation, Coulter counters, and biomolecule detection and nanochannel energy harvesters. In this work we fabricated a polyethylene terephthalate (PET) conical nanochannel using latent ion track etching technique and then systematically studied the ion transport and influence of cation species on the nanochannel surface with cyclic I-V measurement. We discovered the electrical regulation of the reversible and irreversible modification of the nanochannel transportation by bivalent and trivalent cations, revealing the existence of the switching threshold voltage which can control the current rectification in bivalent solution. The proposed mechanism of the transport state transition in the PET nanochannel mimics behaviors of voltage-gated biological ion channels. These findings provide new insight into the understanding of the ion channel signaling and translocation control of charged particles in nanochannel applications.

14.
Vaccines (Basel) ; 7(3)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514454

RESUMO

Duck hepatitis A virus (DHAV) is prevalent worldwide and has caused significant economic losses. As the predominant serotype in China, DHAV-3 has become a major challenge to the local duck industry. Here the genetics and pathogenesis of a virulent DHAV-3 strain and its embryo-passaged strain were assessed. There were only two amino acid substitutions (Y164N in VP0 protein and L71I in 2C protein) introduced during the adaptation process. The pathogenicity of these strains was further evaluated in vivo. Clinical signs, gross pathology, and histopathological analysis showed that the embryo-passaged strain was attenuated. Meanwhile, the viral RNA loads were significantly lower in the liver tissues of the ducklings infected with the attenuated strain. As expected, infection with the virulent and attenuated strains led to the activation of different innate immune genes. We suspected that the loss of replication efficiency in ducklings was responsible for the attenuation phenotype of the embryo-passaged strain. In addition, different innate immune responses in the liver of ducklings were at least partly responsible for the differential infectivity phenotype. These findings provide new insights into the genetics and pathogenesis of DHAV-3, which may aid the development of new vaccines and the implementation of immunization strategies.

15.
Future Microbiol ; 14: 1147-1157, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31368347

RESUMO

Members of the genus Enterovirus have a significant effect on human health, especially in infants and children. Since the viral genome has limited coding capacity, Enteroviruses subvert a range of cellular processes for viral infection via the interaction of viral proteins and numerous cellular factors. Intriguingly, the capsid-receptor interaction plays a crucial role in viral entry and has significant implications in viral pathogenesis. Moreover, interactions between structural proteins and host factors occur directly or indirectly in multiple steps of viral replication. In this review, we focus on the current understanding of the multifunctionality of structural proteins in the viral life cycle, which may constitute valuable targets for antiviral and therapeutic interventions.


Assuntos
Enterovirus/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Proteínas Estruturais Virais/metabolismo , Internalização do Vírus , Replicação Viral , Humanos
16.
J Biomed Inform ; 94: 103177, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30986506

RESUMO

OBJECTIVES: Treatment used in a randomized clinical trial is a critical data element both for physicians at the point of care and reviewers who are evaluating different interventions. Much of existing work on treatment extraction from the biomedical literature has focused on the extraction of pharmacological interventions. However, non-pharmacological interventions (e.g., exercise, diet, etc.) that are frequently used to address chronic conditions are less well studied. The goal of this study is to compare knowledge-based and machine learning strategies for the extraction of both drug and non-drug treatments. METHODS: We collected 800 randomized clinical trial abstracts each for breast cancer and diabetes from PubMed. The treatments in the result/conclusion sentences of the abstracts were manually annotated and marked as drug/non-drug treatments. We then designed three methods to identify the treatments and evaluated the systems with respect to drug/non-drug treatments. The first method is solely based on knowledge base (here we used MetaMap). The second method is based on a machine learning model trained mainly on contextual features (ML_only). The third method is a combination approach that integrates the previous two approaches. RESULTS/DISCUSSION: Results show that MetaMap, when used with high precision semantic types, has better performance for drug compared to non-drug treatments (F1 = 0.77 vs. 0.64). The ML_only approach has smaller performance difference between drug and non-drug treatments compared with the KB-based approach (F1 = 0.02 vs. 0.05, 0.07, and 0.13). The combination approach achieves significantly better performance than all MetaMap approaches alone for total treatments (F1 = 0.76 vs. 0.72, p < 0.001). The performance gain mainly comes from the non-drug treatments (0.03-0.08 improvement in F1), while the drug treatments do not benefit much from the combination approach (0-0.03 improvement in F1). CONCLUSION: These results suggest that a knowledge-based approach should be employed for medical conditions that are primarily treated with drugs whereas conditions that are treated with either a combination of drug and non-drug interventions or primarily non-drug interventions should use automated tools that combine machine learning and a knowledge-based approach to achieve optimal performance.


Assuntos
Tratamento Farmacológico , Automação , Humanos , Aprendizado de Máquina , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
Front Plant Sci ; 10: 406, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024584

RESUMO

Nitrogen (N) is very important for sugarcane yield improvement, but the excessive application of N fertilizer brings about N pollution and a cost increase. Through distinguishing the difference of nitrogen use efficiency (NUE), we can reasonably apply N fertilizer according to the NUE characteristics of sugarcane varieties, and thus reduce N loss and maintain high yield. The present study showed the pot experiment results of identifying NUE types of nine main sugarcane varieties in the main sugarcane producing areas of China under controlled conditions, and identified the key physiological and agronomic indictors which can help to determine the NUE types of sugarcane. The test clones were exposed to varying levels of N fertilizer and 15 parameters that are likely to impact NUE were measured. The key results are (1) Sugarcane variety ROC22 has the high plant dry weight (PDW) and NUE among nine varieties under different N rates, it can take advantages under low N supply (225 kg/hm2 urea), and less N fertilizer can be applied properly in production. (2) Varieties of GT32 was good performing genotype for PDW and NUE under low N supply (225 kg/hm2 urea), GT42 was more suitable for moderate N environment (450 kg/hm2 urea), while YT94-128 was at middle N and high N supply (450-675 kg/hm2 urea). (3) Late stage of shoot elongation is suitable for differentiating sugarcane clones for NUE. (4) Leaf glutamine synthetase activity is the most reliable predictor of NUE in sugarcane. The result of pot experiment is sufficient to differentiate clonal variation for NUE in sugarcane as it reflects field experimental results. This study can set up a basis for identification the NUE types of sugarcane varieties and the development of reasonable N fertilizer application.

18.
J Agric Food Chem ; 67(15): 4346-4354, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30901210

RESUMO

Dietary flavonoids are known as scavengers of reactive oxygen species such as hypochlorous acid. In spite of the abundant scavenging capacity data reported, few reports have addressed the relationship between the scavenging capacity and structures of different flavonoids. We characterized the reaction products of five flavonoids (apigenin, quercetin, naringenin, ampelopsin, and epicatechin) with hypochlorous acid and found that primary chlorination reaction occurred on the A-ring (C6 or C8) and/or C-rings but not on B-rings. Correlation of the hypochlorous acid scavenging capacity (IC50 values) and the structural features of flavonoids revealed that the hydroxyl groups in the A-ring and B-ring can enhance the scavenging capacity, whereas the C(2)C(3) double bond has a negative impact on the HClO scavenging capacity. Combining the SAR analysis and chemical study, we proposed that the reaction mechanism between flavonoids and HClO should be an electrophilic substitution reaction. Density functional theory (DFT) results are consistent with the selectivity of chlorination on the flavonoids. Our findings highlight the importance of considering specific reactive oxygen species when measuring radical scavenging capacity of dietary antioxidants.


Assuntos
Antioxidantes/química , Flavonoides/química , Ácido Hipocloroso/química , Halogenação , Estrutura Molecular , Relação Estrutura-Atividade
19.
BMC Plant Biol ; 18(1): 342, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30526526

RESUMO

BACKGROUND: Sugarcane (Saccharum spp. hybrids) is considered the most globally important sugar-producing crop and raw material for biofuel. Insect attack is a major issue in sugarcane cultivation, resulting in yield losses and sucrose content reductions. Stem borer (Diatraea saccharalis F.) causes serious yield losses in sugarcane worldwide. However, insect-resistant germplasms for sugarcane are not available in any collections all over the world, and the molecular mechanism of insect resistance has not been elucidated. In this study, cry1Ac transgenic sugarcane lines were obtained and the biological characteristics and transgene dosage effect were investigated and a global exploration of gene expression by transcriptome analysis was performed. RESULTS: The transgene copies of foreign cry1Ac were variable and random. The correlation between the cry1Ac protein and cry1Ac gene copies differed between the transgenic lines from FN15 and ROC22. The medium copy lines from FN15 showed a significant linear relationship, while ROC22 showed no definite dosage effect. The transgenic lines with medium copies of cry1Ac showed an elite phenotype. Transcriptome analysis by RNA sequencing indicated that up/down regulated differentially expressed genes were abundant among the cry1Ac sugarcane lines and the receptor variety. Foreign cry1Ac gene and endogenous borer stress-related genes may have a synergistic effect. Three lines, namely, A1, A5, and A6, were selected for their excellent stem borer resistance and phenotypic traits and are expected to be used directly as cultivars or crossing parents for sugarcane borer resistance breeding. CONCLUSIONS: Cry1Ac gene integration dramatically improved sugarcane insect resistance. The elite transgenic offspring contained medium transgene copies. Foreign cry1Ac gene integration and endogenous borer stress-related genes may have a synergistic effect on sugarcane insect resistance improvement.


Assuntos
Proteínas de Bactérias/genética , Endotoxinas/genética , Genes de Plantas/genética , Proteínas Hemolisinas/genética , Mariposas , Saccharum/genética , Animais , Toxinas de Bacillus thuringiensis , Produção Agrícola , Herbivoria , Larva , Melhoramento Vegetal/métodos , Plantas Geneticamente Modificadas , Saccharum/parasitologia , Estresse Fisiológico/genética
20.
PeerJ ; 6: e5873, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30402355

RESUMO

Glyoxalase I belongs to the glyoxalase system that detoxifies methylglyoxal (MG), a cytotoxic by-product produced mainly from triose phosphates. The concentration of MG increases rapidly under stress conditions. In this study, a novel glyoxalase I gene, designated as SoGloI was identified from sugarcane. SoGloI had a size of 1,091 bp with one open reading frame (ORF) of 885 bp encoding a protein of 294 amino acids. SoGloI was predicted as a Ni2+-dependent GLOI protein with two typical glyoxalase domains at positions 28-149 and 159-283, respectively. SoGloI was cloned into an expression plasmid vector, and the Trx-His-S-tag SoGloI protein produced in Escherichia coli was about 51 kDa. The recombinant E. coli cells expressing SoGloI compared to the control grew faster and tolerated higher concentrations of NaCl, CuCl2, CdCl2, or ZnSO4. SoGloI ubiquitously expressed in various sugarcane tissues. The expression was up-regulated under the treatments of NaCl, CuCl2, CdCl2, ZnSO4 and abscisic acid (ABA), or under simulated biotic stress conditions upon exposure to salicylic acid (SA) and methyl jasmonate (MeJA). SoGloI activity steadily increased when sugarcane was subjected to NaCl, CuCl2, CdCl2, or ZnSO4 treatments. Sub-cellular observations indicated that the SoGloI protein was located in both cytosol and nucleus. These results suggest that the SoGloI gene may play an important role in sugarcane's response to various biotic and abiotic stresses.

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