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1.
Small ; 19(38): e2303319, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194967

RESUMO

Photo-rechargeable (solar) battery can be considered as an energy harvesting cum storage system, where it can charge the conventional metal-ion battery using light instead of electricity, without having other parasitic reactions. Here a two-electrode lithium-ion solar battery with multifaceted TiS2 -TiO2 hybrid sheets as cathode. The choice of TiS2 -TiO2 electrode ensures the formation of a type II semiconductor heterostructure while the lateral heterostructure geometry ensures high mass/charge transfer and light interactions with the electrode. TiS2 has a higher lithium binding energy (1.6 eV) than TiO2 (1.03 eV), ensuring the possibilities of higher amount of Li-ion insertion to TiS2 and hence the maximum recovery with the photocharging, as further confirmed by the experiments. Apart from the demonstration of solar solid-state batteries, the charging of lithium-ion full cell with light indicates the formation of lithium intercalated graphite compounds, ensuring the charging of the battery without any other parasitic reactions at the electrolyte or electrode-electrolyte interfaces. Possible mechanisms proposed here for the charging and discharging processes of solar batteries, based on the experimental and theoretical results, indicate the potential of such systems in the forthcoming era of renewable energies.

2.
Angew Chem Int Ed Engl ; 61(28): e202202637, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35362643

RESUMO

Herein we report secondary pyrrolidin-2-ols as a source of cyclic (alkyl)(amino)carbenes (CAAC) for the synthesis of CAAC-CuI -complexes and cyclic thiones when reacted with CuI -salts and elemental sulfur, respectively, under reductive elimination of water from the carbon(IV)-center. This result demonstrates a convenient and facile access to CAAC-based CuI -salts, which are well known catalysts for different organic transformations. It further establishes secondary alcohols to be a viable source of carbenes-realizing after 185 years Dumas' dream who tried to prepare the parent carbene (CH2 ) by 1,1-dehydration of methanol. Addressed is also the reactivity of water towards CAACs, which proceeds through an oxidative addition of the O-H bond to the carbon(II)-center. This emphasizes the ability of carbon-compounds to mimic the reactivity of transition-metal complexes: reversible oxidative addition and reductive elimination of the O-H bond to/from the C(II)/C(IV)-centre.

3.
Small ; 17(51): e2105029, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34786850

RESUMO

New ways of directly using solar energy to charge electrochemical energy storage devices such as batteries would lead to exciting developments in energy technologies. Here, a two-electrode photo rechargeable Li-ion battery is demonstrated using nanorod of type II semiconductor heterostructures with in-plane domains of crystalline MoS2 and amorphous MoOx . The staggered energy band alignment of MoS2 and MoOx limits the electron holes recombination and causes holes to be retained in the Li intercalated MoS2 electrode. The holes generated in the MoS2 pushes the intercalated Li-ions and hence charge the battery. Low band gap, high efficiency photo-conversion and efficient electron-hole separation help the battery to fully charge within a few hours using solar light. The proposed concept and materials can enable next generation stable photo-rechargeable battery electrodes, in contrast to the reported materials.

4.
J Exp Bot ; 71(17): 5280-5293, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32526034

RESUMO

Limited information is available on abiotic stress-mediated alterations of chromatin conformation influencing gene expression in plants. In order to characterize the effect of abiotic stresses on changes in chromatin conformation, we employed FAIRE-seq (formaldehyde-assisted isolation of regulatory element sequencing) and DNase-seq to isolate accessible regions of chromatin from Arabidopsis thaliana seedlings exposed to either heat, cold, salt, or drought stress. Approximately 25% of regions in the Arabidopsis genome were captured as open chromatin, the majority of which included promoters and exons. A large proportion of chromatin regions apparently did not change their conformation in response to any of the four stresses. Digital footprints present within these regions had differential enrichment of motifs for binding of 43 different transcription factors. Further, in contrast to drought and salt stress, both high and low temperature treatments resulted in increased accessibility of the chromatin. Also, pseudogenes attained increased chromatin accessibility in response to cold and drought stresses. The highly accessible and inaccessible chromatin regions of seedlings exposed to drought stress correlated with the Ser/Thr protein kinases (MLK1 and MLK2)-mediated reduction and increase in H3 phosphorylation (H3T3Ph), respectively. The presented results provide a deeper understanding of abiotic stress-mediated chromatin modulation in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Cromatina , Secas , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico
5.
Opt Lett ; 44(7): 1770-1773, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30933143

RESUMO

We design and experimentally demonstrate a broadband 1310/1550 nm wavelength demultiplexer based on a multimode interference coupler with a tapered internal photonic crystal (PC) structure for the silicon-on-insulator platform. The tapered internal PC structure is engineered to reflect the C-band light while transmitting the O-band light. Novel PC nanotapers are introduced for the internal PC structure that effectively suppress the sidelobe of the photonic bandgap and enable our device to be operable over the O-band. The device was fabricated using electron beam lithography, and its performance has been experimentally characterized. The measured extinction ratios are higher than 15 dB over a 74 nm bandwidth from 1286 to 1360 nm at the O-band, and over a 103 nm bandwidth from 1527 to 1630 nm that covers the C-band and the L-band.

6.
Int J Urol ; 26(5): 551-557, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30803052

RESUMO

OBJECTIVE: To assess renal unit survival and factors affecting renal salvageability in a cohort of patients receiving modern medical and surgical therapy for urinary tuberculosis. METHODS: This was a retrospective single-center study including all patients diagnosed and treated as urinary tuberculosis between 2005 and 2015 at Christian Medical College, Vellore, Tamil Nadu, India. The primary outcome was time to renal unit non-salvageability (estimated glomerular filtration rate of <15 mL/min). RESULTS: A total of 128 patients were included in the study. The mean age was 37.7 ± 11.3 years, 33% had microbiological and 73% had histopathological confirmation in addition to radiological diagnosis. The estimated median survival of the involved renal units (n = 187) on Kaplan-Meier estimate was 75 months (95% CI 39-99). On multivariate analysis, renal units with initial split function >15 mL/min had fivefold the survival estimate as compared with those ≤15 mL/min (P < 0.001); the presence of one, two and three infundibular strictures had a 2.2-, 2.9- and fivefold higher hazard of renal unit loss respectively, and lower ureteric strictures had fivefold longer estimated survival (P = 0.015) after treatment. Renal units in the reconstruction group had 5.44-fold (95% CI 2.71-10.88, P < 0.001) longer survival than the permanent diversion group, with a mean change in split function of +0.76 (±16.11) mL/min, versus -5.61 (±10.87) mL/min respectively. CONCLUSIONS: Loss of renal units is a function of time despite modern treatment. Baseline renal unit function, site of ureteric involvement and extent of infundibular involvement on imaging are helpful in predicting the duration of renal salvageability. When feasible, reconstruction is better at renal function preservation.


Assuntos
Rim/cirurgia , Tuberculose Urogenital/terapia , Adulto , Antituberculosos/uso terapêutico , Feminino , Taxa de Filtração Glomerular , Humanos , Índia , Estimativa de Kaplan-Meier , Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mycobacterium tuberculosis/efeitos dos fármacos , Nefrectomia , Valor Preditivo dos Testes , Radiografia , Estudos Retrospectivos , Terapia de Salvação , Tuberculose Urogenital/diagnóstico por imagem , Ultrassonografia
7.
Opt Express ; 26(23): 29873-29885, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30469946

RESUMO

We demonstrate a compact high-performance adiabatic 3-dB coupler for the silicon-on-insulator platform. The refractive index of the gap region between two coupling waveguides is effectively increased using subwavelength grating, which leads to high-performance operation and a compact design footprint, with a mode-evolution length of only 25 µm and an entire device length of 65 µm. The designed adiabatic 3-dB coupler has been fabricated using electron beam lithography and the feature size used in our design is CMOS compatible. The fabricated device is characterized in the wavelength range from 1500 nm to 1600 nm, with a measured power splitting ratio better than 3 ± 0.27 dB and an average insertion loss of 0.20 dB.

8.
Opt Express ; 26(16): 19742-19749, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30119295

RESUMO

We present the first demonstration of a 4λ transmitter optical sub-assembly (TOSA) on the coarse wavelength division multiplexing (CWDM) grid, i.e., 20 nm spacing, targeting 400G-FR4 requirements over 2 km. The TOSA is based on uncooled InP external modulated laser (EML) technology and it utilizes four EMLs followed by a CWDM multiplexer. We characterize the performance of the TOSA versus received optical modulation amplitude (OMA), number of equalizer taps, reach, modulation format, TOSA case temperature, and bit rate. Four 53 Gbaud 4-level pulse amplitude modulation (PAM4) RF signals are used to drive the TOSA achieving a net rate of 400 Gb/s. Results reveal that 400 Gb/s can be transmitted over 2 km of single mode fiber (SMF) at a bit error rate (BER) below the KP4- forward error correction (KP4-FEC) threshold (i.e., 2.4 × 10-4) using only a 5 tap feed forward equalizer at the receiver. To the best of our knowledge, this is the first demonstration of 400 Gb/s using a 4λ CWDM TOSA over 2 km of SMF. Moreover, we achieve 400 Gb/s and 600 Gb/s over 20 km and 10 km below KP4-FEC and the 7% hard-decision FEC (HD-FEC) (i.e., 3.8 × 10-3) thresholds, respectively, without optical amplification. Furthermore, we show the performance of the TOSA against temperature, where it shows no significant change in the BER performance from 20 °C to 60 °C. Finally, we compare the performance of PAM2, PAM4, and PAM8 modulation formats where we show the possibility of achieving 400 Gb/s aggregate bit rate using 42 Gbaud PAM8 modulation format at the expense of utilizing a stronger FEC.

9.
Opt Express ; 25(24): 30582-30590, 2017 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-29221085

RESUMO

We demonstrate two single-etched sub-wavelength grating coupler (SWGC) designs for O-band application, one targeting at high coupling efficiency and the other targeting at broad operating bandwidth. The high-efficiency SWGC has a measured peak coupling efficiency of -3.8 dB and a 3-dB bandwidth of 40 nm, and the broadband SWGC has a measured peak coupling efficiency of -4.3 dB and a 3-dB bandwidth of 71 nm. Focusing gratings have been used in our SWGCs to reduce the design footprints and the dimensions of our SWGCs are smaller than 45 µm × 24 µm. The back reflections of our SWGCs are suppressed to be below -15 dB over the wavelength range from 1260 nm to 1360 nm.

10.
BMC Plant Biol ; 15: 9, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25604693

RESUMO

BACKGROUND: Brassica juncea var. Varuna is an economically important oilseed crop of family Brassicaceae which is vulnerable to abiotic stresses at specific stages in its life cycle. Till date no attempts have been made to elucidate genome-wide changes in its transcriptome against high temperature or drought stress. To gain global insights into genes, transcription factors and kinases regulated by these stresses and to explore information on coding transcripts that are associated with traits of agronomic importance, we utilized a combinatorial approach of next generation sequencing and de-novo assembly to discover B. juncea transcriptome associated with high temperature and drought stresses. RESULTS: We constructed and sequenced three transcriptome libraries namely Brassica control (BC), Brassica high temperature stress (BHS) and Brassica drought stress (BDS). More than 180 million purity filtered reads were generated which were processed through quality parameters and high quality reads were assembled de-novo using SOAPdenovo assembler. A total of 77750 unique transcripts were identified out of which 69,245 (89%) were annotated with high confidence. We established a subset of 19110 transcripts, which were differentially regulated by either high temperature and/or drought stress. Furthermore, 886 and 2834 transcripts that code for transcription factors and kinases, respectively, were also identified. Many of these were responsive to high temperature, drought or both stresses. Maximum number of up-regulated transcription factors in high temperature and drought stress belonged to heat shock factors (HSFs) and dehydration responsive element-binding (DREB) families, respectively. We also identified 239 metabolic pathways, which were perturbed during high temperature and drought treatments. Analysis of gene ontologies associated with differentially regulated genes forecasted their involvement in diverse biological processes. CONCLUSIONS: Our study provides first comprehensive discovery of B. juncea transcriptome under high temperature and drought stress conditions. Transcriptome resource generated in this study will enhance our understanding on the molecular mechanisms involved in defining the response of B. juncea against two important abiotic stresses. Furthermore this information would benefit designing of efficient crop improvement strategies for tolerance against conditions of high temperature regimes and water scarcity.


Assuntos
Produtos Agrícolas/economia , Produtos Agrícolas/genética , Secas , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Mostardeira/genética , Estresse Fisiológico/genética , Temperatura , Perfilação da Expressão Gênica , Ontologia Genética , Anotação de Sequência Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Controle de Qualidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Análise de Sequência de RNA , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcriptoma
11.
BMC Plant Biol ; 14: 6, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24397411

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are ubiquitous components of endogenous plant transcriptome. miRNAs are small, single-stranded and ~21 nt long RNAs which regulate gene expression at the post-transcriptional level and are known to play essential roles in various aspects of plant development and growth. Previously, a number of miRNAs have been identified in potato through in silico analysis and deep sequencing approach. However, identification of miRNAs through deep sequencing approach was limited to a few tissue types and developmental stages. This study reports the identification and characterization of potato miRNAs in three different vegetative tissues and four stages of tuber development by high throughput sequencing. RESULTS: Small RNA libraries were constructed from leaf, stem, root and four early developmental stages of tuberization and subjected to deep sequencing, followed by bioinformatics analysis. A total of 89 conserved miRNAs (belonging to 33 families), 147 potato-specific miRNAs (with star sequence) and 112 candidate potato-specific miRNAs (without star sequence) were identified. The digital expression profiling based on TPM (Transcripts Per Million) and qRT-PCR analysis of conserved and potato-specific miRNAs revealed that some of the miRNAs showed tissue specific expression (leaf, stem and root) while a few demonstrated tuberization stage-specific expressions. Targets were predicted for identified conserved and potato-specific miRNAs, and predicted targets of four conserved miRNAs, miR160, miR164, miR172 and miR171, which are ARF16 (Auxin Response Factor 16), NAM (NO APICAL MERISTEM), RAP1 (Relative to APETALA2 1) and HAM (HAIRY MERISTEM) respectively, were experimentally validated using 5' RLM-RACE (RNA ligase mediated rapid amplification of cDNA ends). Gene ontology (GO) analysis for potato-specific miRNAs was also performed to predict their potential biological functions. CONCLUSIONS: We report a comprehensive study of potato miRNAs at genome-wide level by high-throughput sequencing and demonstrate that these miRNAs have tissue and/or developmental stage-specific expression profile. Also, predicted targets of conserved miRNAs were experimentally confirmed for the first time in potato. Our findings indicate the existence of extensive and complex small RNA population in this crop and suggest their important role in pathways involved in diverse biological processes, including tuber development.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Folhas de Planta/genética , Raízes de Plantas/genética , Caules de Planta/genética , RNA de Plantas/genética , Análise de Sequência de RNA/métodos , Solanum tuberosum/genética , Regulação da Expressão Gênica de Plantas
12.
ACS Appl Mater Interfaces ; 16(7): 8627-8638, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38345507

RESUMO

Chemical stability of hexagonal boron nitride (hBN) ultrathin layers in harsh electrolytes and the availability of nitrogen site in hBN to stabilize metals like Pt are used here to develop a high intrinsic activity hydrogen evolution reaction (HER) catalyst having low loaded Pt (5 weight% or <1 atomic%). A catalyst having a nonzero oxidation state for Pt (with a Pt-N bonding) is shown to be HER active even with low catalyst loadings (0.114 mgcm-2). Electronic modification of the shear exfoliated hBN sheets is achieved by Au nanoparticle-based surface decoration (hBN_Au), and further anchoring with Pt develops a catalyst (hBN_Au_Pt) with high turnover frequency for HER (∼15). The hBN_Au_Pt is shown to be a highly durable catalyst even after the accelerated durability test for 10000 cycles and temperature annealing at 100 °C. Density functional theory based calculations gave insights in to the electronic modifications of hBN with Au and the catalytic activity of the hBN_Au_Pt system, in line with the experimental studies, indicating the demonstration of a new class of catalyst system devoid of issues such as carbon corrosion and Pt leaching.

13.
Nanoscale ; 15(30): 12694-12709, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37470330

RESUMO

Layered transition metal dichalcogenides (TMDs) have shown commendable properties for spintronic applications. From the device perspective, the structural quality of the TMD as well as its interface with the adjacent ferromagnetic (FM) layer is of paramount importance. Here, we present the spin-dynamic behaviour in the widely studied TMDs, i.e., MoS2 using Co60Fe20B20 (CoFeB), i.e., in MoS2(1-4 layers)/CoFeB(4-15 nm) heterostructures, both in the as-grown state and in the in situ annealed state (400 °C in a vacuum). Raman spectroscopy revealed systematic variation in the separation (δ) between the characteristic Raman shifts corresponding to the E2g and A1gvis-à-vis the number of layers (nL) of MoS2. The analysis of the ferromagnetic resonance (FMR) spectroscopy measurements performed on these heterostructures revealed the spin pumping from CoFeB to the MoS2 layer as evidenced by the ∼49% (∼51%) enhancement in the effective damping parameter with respect to the damping parameter of bare as-deposited (annealed) CoFeB films. This enhancement is attributed to the spin-pumping owing to the high spin-orbit coupling of monolayer MoS2. The latter is also confirmed by density functional theory calculations. By finding the effective spin mixing conductance of the MoS2/CoFeB interface, the effective spin current density in the MoS2 layer is estimated to increase from ∼0.3 to 0.7 MA m-2 with CoFeB thickness for both the as-deposited and annealed heterostructures. Furthermore, the δ vs. nL curve of the as-deposited heterostructure did not show any significant change upon annealing, which demonstrated that the spin transport and magnetic properties of these heterostructures remained unaffected even after annealing at a high temperature of 400 °C. Hence, this establishes the high thermal stability of the sputter grown MoS2/CoFeB heterostructures. Thus, this study highlights the important role of MoS2 as an efficient spin current-generating source for spin-orbit torque based magnetic memory applications, given the high-temperature stability and high-quality monolayers of MoS2 and its excellent performance with CoFeB thin films.

14.
Nanoscale ; 15(1): 337-349, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36503983

RESUMO

Spin gapless semiconductors (SGSs) are an intriguing class of quantum materials that bridge the gap between half-metallic ferromagnets and semiconductors. The presence of a semiconducting bandgap for one spin channel and zero band gap for other spin channels, together with the possibility of four different band structure configurations, makes them one of the most desirable candidates to be used in tunable spin transport based spintronics devices. Here, we have performed various structural, magnetic and transport measurements on an optimized CoFeCrGa (CFCG) Heusler alloy thin film (∼50 nm) grown over a Si(100) substrate using an industry-viable magnetron sputtering technique. The grown film showed B2-ordering under the given set of X-ray diffraction measurement conditions with a saturation magnetization (Ms) of 1.86µB per f.u. (at 5 K) and a Curie temperature of ∼595 K. Nearly linearly varying longitudinal resistivity with a negative temperature coefficient was observed. A fitted longitudinal conductivity curve through a "two-carrier model" shows a slight band overlap in the gapless channel for one spin channel and a small energy gap (ΔE) of 167 meV for other spin channels. A negative and linear out-of-plane magnetoresistance response was observed in these films. The temperature dependent anomalous Hall effect measurement gives nearly temperature independent carrier concentration (and/or) mobility with an anomalous Hall conductivity of 91.35 S cm-1 at 5 K. The first principles calculations have also been performed for bulk and (220) CFCG surfaces to correlate the various structural, electronics and magnetic properties of the optimized CFCG Heusler alloy thin film. The DFT derived results, viz. lattice parameter and MS exhibit a good match with the experimentally observed results. All these properties collectively imply that the grown film possesses disordered-SGS like behaviour. It is remarkable to note that CFCG films with the (022) surface possess a very high electronic spin polarization of 91%. The results of the study suggest that CFCG is a potential candidate to be used in spintronics-based devices such as spin-injectors.

15.
Plant Genome ; 15(3): e20234, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35762493

RESUMO

Black gram [Vigna mungo (L.) Hepper var. mungo] is a warm-season legume highly prized for its protein content along with significant folate and iron proportions. To expedite the genetic enhancement of black gram, a high-quality draft genome from the center of origin of the crop is indispensable. Here, we established a draft genome sequence of an Indian black gram cultivar, 'Uttara' (IPU 94-1), known for its high resistance to mungbean yellow mosaic virus. Pacific Biosciences of California, Inc. (PacBio) single-molecule real-time (SMRT) and Illumina sequencing assembled a draft reference-guided assembly with a cumulative size of ∼454.4 Mb, of which, 444.4 Mb was anchored on 11 pseudomolecules corresponding to 11 chromosomes. Uttara assembly denotes features of a high-quality draft genome illustrated through high N50 value (42.88 Mb), gene completeness (benchmarking universal single-copy ortholog [BUSCO] score 94.17%) and low levels of ambiguous nucleotides (N) percent (0.0005%). Gene discovery using transcript evidence predicted 28,881 protein-coding genes, from which, ∼95% were functionally annotated. A global survey of genes associated with disease resistance revealed 119 nucleotide binding site-leucine rich repeat (NBS-LRR) proteins, while 23 genes encoding seed storage proteins (SSPs) were discovered in black gram. A large set of microsatellite loci were discovered for marker development in the crop. Our draft genome of an Indian black gram provides the foundational genomic resources for the improvement of important agronomic traits and ultimately will help in accelerating black gram breeding programs.


Assuntos
Vigna , Resistência à Doença/genética , Ácido Fólico , Ferro , Leucina/genética , Nucleotídeos , Melhoramento Vegetal , Proteínas de Armazenamento de Sementes/genética , Análise de Sequência de DNA , Vigna/genética
16.
Trends Genet ; 22(7): 396-403, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16723170

RESUMO

Parasitic nematodes infect thousands of plant species, but some plants harbor specific resistance genes that defend against these pests. Several nematode resistance genes have been cloned in plants, and most resemble other plant resistance genes. Nematode resistance is generally characterized by host plant cell death near or at the feeding site of the endoparasitic worm. The timing and localization of the resistance response varies with the particular resistance gene and nematode interaction. Although there is genetic evidence that single genes in the nematode can determine whether a plant mounts a resistance response, cognate nematode effectors corresponding to a plant resistance gene have not been identified. However, recent progress in genetics and genomics of both plants and nematodes, and developments in RNA silencing strategies are improving our understanding of the molecular players in this complex interaction. In this article, we review the nature and mechanisms of plant-nematode interactions with respect to resistance in plants.


Assuntos
Genes de Plantas , Nematoides/fisiologia , Doenças das Plantas/genética , Plantas/genética , Animais , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/parasitologia , Plantas/imunologia , Plantas/parasitologia , Interferência de RNA , Transdução de Sinais
18.
Leukemia ; 33(7): 1675-1686, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30664664

RESUMO

p97 is an ATPase that works in concert with histone deacetylase 6 (HDAC6), to facilitate the degradation of misfolded proteins by autophagosomes. p97 has also been implicated in DNA repair and maintaining genomic stability. In this study, we determined the effect of combined inhibition of p97 and HDAC6 activities in mantle cell lymphoma (MCL) cells. We report that treatment with p97 inhibitors induces dose-dependent apoptosis in MCL cells. The p97 inhibitor CB-5083 induces ER stress markers GRP78 and CHOP and results in the accumulation of polyubiquitylated proteins. Co-treatment with CB-5083 and the HDAC6 inhibitor ACY-1215 result in marked downregulation of CDK4, Cyclin D1, and BRCA1 levels without inhibiting autophagic flux. Consequently, treatment with CB-5083 accentuates DNA damage in response to treatment with ACY-1215 resulting in enhanced accumulation of H2AX-γ and synergistic apoptosis. Furthermore, ATM loss severely impairs phosphorylation of 53BP1 following co-treatment with CB-5083 and ACY-1215 in response to gamma irradiation. Finally, co-treatment CB-5083 and ACY-1215 results in reduced tumor volumes and improves survival in Z138C and Jeko-1 xenografts in NSG mice. These observations suggest that combined inhibition of p97 and HDAC6 abrogates resolution of proteotoxic stress and impairs DNA repair mechanisms in MCL cells.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Reparo do DNA/efeitos dos fármacos , Sinergismo Farmacológico , Desacetilase 6 de Histona/antagonistas & inibidores , Ácidos Hidroxâmicos/farmacologia , Indóis/farmacologia , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/genética , Proteínas Nucleares/antagonistas & inibidores , Pirimidinas/farmacologia , Animais , Apoptose , Autofagia , Proliferação de Células , Dano ao DNA/efeitos dos fármacos , Quimioterapia Combinada , Chaperona BiP do Retículo Endoplasmático , Regulação Neoplásica da Expressão Gênica , Inibidores de Histona Desacetilases/farmacologia , Humanos , Linfoma de Célula do Manto/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Front Plant Sci ; 9: 402, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29651296

RESUMO

Carthamus tinctorius L. (safflower) is an important oilseed crop producing seed oil rich in unsaturated fatty acids. Scarcity of identified marker-trait associations is a major limitation toward development of successful marker-assisted breeding programs in safflower. In the present study, a safflower panel (CartAP) comprising 124 accessions derived from two core collections was assayed for its suitability for association mapping. Genotyping of CartAP using microsatellite markers revealed significant genetic diversity indicated by Shannon information index (H = 0.7537) and Nei's expected heterozygosity (I = 0.4432). In Principal Coordinate Analysis, the CartAP accessions were distributed homogeneously in all quadrants indicating their diverse nature. Distance-based Neighbor Joining analysis did not delineate the CartAP accessions in consonance with their geographical origin. Bayesian analysis of population structure of CartAP demonstrated the unstructured nature of the association panel. Kinship analysis at population (Gij ) and individual level (Fij ) revealed absence of or weak relatedness between the CartAP accessions. The above parameters established the suitability of CartAP for association mapping. We performed association mapping using phenotypic data for eight traits of agronomic value (viz., seed oil content, oleic acid, linoleic acid, plant height, number of primary branches, number of capitula per plant, 100-seed weight and days to 50% flowering) available for two growing seasons (2011-2012 and 2012-2013) through General Linear Model and Mixed Linear Model. Our study identified ninety-six significant marker-trait associations (MTAs; P < 0.05) of which, several MTAs with correlation coefficient (R2) > 10% were consistently represented in both models and in both seasons for traits viz., oil content, oleic acid content, linoleic acid content and number of primary branches. Several MTAs with high R2-values were detected either in a majority or in some environments (models and/or seasons). Many MTAs were also common between traits (viz., oleic/linoleic acid content; plant height/days to 50% flowering; number of primary branches/number of capitula per plant) that showed positive or negative correlation in their phenotypic values. The marker-trait associations identified in this study will facilitate marker-assisted breeding and identification of genetic determinants of trait variability.

20.
Mol Plant Pathol ; 19(3): 615-633, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28220591

RESUMO

Root-knot nematodes (RKNs, Meloidogyne incognita) are economically important endoparasites with a wide host range. We used a comprehensive transcriptomic approach to investigate the expression of both tomato and RKN genes in tomato roots at five infection time intervals from susceptible plants and two infection time intervals from resistant plants, grown under soil conditions. Differentially expressed genes during susceptible (1827, tomato; 462, RKN) and resistance (25, tomato; 160, RKN) interactions were identified. In susceptible responses, tomato genes involved in cell wall structure, development, primary and secondary metabolite, and defence signalling pathways, together with RKN genes involved in host parasitism, development and defence, are discussed. In resistance responses, tomato genes involved in secondary metabolite and hormone-mediated defence responses, together with RKN genes involved in starvation stress-induced apoptosis, are discussed. In addition, 40 novel differentially expressed RKN genes encoding secretory proteins were identified. Our findings provide novel insights into the temporal regulation of genes involved in various biological processes from tomato and RKN simultaneously during susceptible and resistance responses, and reveal the involvement of a complex network of biosynthetic pathways during disease development.


Assuntos
Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Solanum lycopersicum/genética , Solanum lycopersicum/parasitologia , Transcriptoma/genética , Tylenchoidea/patogenicidade , Animais , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/fisiologia , Solanum lycopersicum/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/parasitologia
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