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1.
Plant Physiol ; 194(3): 1794-1814, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38036294

RESUMEN

Bud dormancy is an important physiological process during winter. Its release requires a certain period of chilling. In pear (Pyrus pyrifolia), the abscisic acid (ABA)-induced expression of DORMANCY-ASSOCIATED MADS-box (DAM) genes represses bud break, whereas exogenous gibberellin (GA) promotes dormancy release. However, with the exception of ABA and GA, the regulatory effects of phytohormones on dormancy remain largely uncharacterized. In this study, we confirmed brassinosteroids (BRs) and jasmonic acid (JA) contribute to pear bud dormancy release. If chilling accumulation is insufficient, both 24-epibrassinolide (EBR) and methyl jasmonic acid (MeJA) can promote pear bud break, implying that they positively regulate dormancy release. BRASSINAZOLE RESISTANT 2 (BZR2), which is a BR-responsive transcription factor, inhibited PpyDAM3 expression and accelerated pear bud break. The transient overexpression of PpyBZR2 increased endogenous GA, JA, and JA-Ile levels. In addition, the direct interaction between PpyBZR2 and MYELOCYTOMATOSIS 2 (PpyMYC2) enhanced the PpyMYC2-mediated activation of Gibberellin 20-oxidase genes PpyGA20OX1L1 and PpyGA20OX2L2 transcription, thereby increasing GA3 contents and accelerating pear bud dormancy release. Interestingly, treatment with 5 µm MeJA increased the bud break rate, while also enhancing PpyMYC2-activated PpyGA20OX expression and increasing GA3,4 contents. The 100 µm MeJA treatment decreased the PpyMYC2-mediated activation of the PpyGA20OX1L1 and PpyGA20OX2L2 promoters and suppressed the inhibitory effect of PpyBZR2 on PpyDAM3 transcription, ultimately inhibiting pear bud break. In summary, our data provide insights into the crosstalk between the BR and JA signaling pathways that regulate the BZR2/MYC2-mediated pathway in the pear dormancy release process.


Asunto(s)
Brasinoesteroides , Ciclopentanos , Oxilipinas , Pyrus , Triazoles , Brasinoesteroides/farmacología , Pyrus/genética , Reguladores del Crecimiento de las Plantas/farmacología , Ácido Abscísico
2.
Small ; : e2402427, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38751309

RESUMEN

Halogenated methane serves as a universal platform molecule for building high-value chemicals. Utilizing sodium chloride solution for photocatalytic methane chlorination presents an environmentally friendly method for methane conversion. However, competing reactions in gas-solid-liquid systems leads to low efficiency and selectivity in photocatalytic methane chlorination. Here, an in situ method is employed to fabricate a hydrophobic layer of TaOx species on the surface of NaTaO3. Through in-situ XPS and XANES spectra analysis, it is determined that TaOx is a coordination unsaturated species. The TaOx species transforms the surface properties from the inherent hydrophilicity of NaTaO3 to the hydrophobicity of TaOx/NaTaO3, which enhances the accessibility of CH4 for adsorption and activation, and thus promotes the methane chlorination reaction within the gas-liquid-solid three-phase system. The optimized TaOx/NaTaO3 photocatalyst has a good durability for multiple cycles of methane chlorination reactions, yielding CH3Cl at a rate of 233 µmol g-1 h-1 with a selectivity of 83%. In contrast, pure NaTaO3 exhibits almost no activity toward CH3Cl formation, instead catalyzing the over-oxidation of CH4 into CO2. Notably, the activity of the optimized TaOx/NaTaO3 photocatalyst surpasses that of reported noble metal photocatalysts. This research offers an effective strategy for enhancing the selectivity of photocatalytic methane chlorination using inorganic chlorine ions.

3.
Environ Sci Technol ; 58(26): 11843-11854, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38952299

RESUMEN

Advanced oxidation processes (AOPs) are the most efficient water cleaning technologies, but their applications face critical challenges in terms of mass/electron transfer limitations and catalyst loss/deactivation. Bipolar electrochemistry (BPE) is a wireless technique that is promising for energy and environmental applications. However, the synergy between AOPs and BPE has not been explored. In this study, by combining BPE with AOPs, we develop a general approach of using carbon nanotubes (CNTs) as electric-field-induced bipolar electrodes to control electron transfer for efficient water purification. This approach can be used for permanganate and peroxide activation, with superior performances in the degradation of refractory organic pollutants and excellent durability in recycling and scale-up experiments. Theoretical calculations, in situ measurements, and physical experiments showed that an electric field could substantially reduce the energy barrier of electron transfer over CNTs and induce them to produce bipolar electrodes via electrochemical polarization or to form monopolar electrodes through a single particle collision effect with feeding electrodes. This approach can continuously provide activated electrons from one pole of bipolar electrodes and simultaneously achieve "self-cleaning" of catalysts through CNT-mediated direct oxidation from another pole of bipolar electrodes. This study provides a fundamental scientific understanding of BPE, expands its scope in the environmental field, and offers a general methodology for water purification.


Asunto(s)
Electrodos , Nanotubos de Carbono , Oxidación-Reducción , Purificación del Agua , Nanotubos de Carbono/química , Purificación del Agua/métodos , Catálisis
4.
Small ; 19(26): e2207919, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36938911

RESUMEN

Constructing active heterointerfaces is powerful to enhance the electrochemical performances of transition metal dichalcogenides, but the interface density regulation remains a huge challenge. Herein, MoO2 /MoS2 heterogeneous nanorods are encapsulated in nitrogen and sulfur co-doped carbon matrix (MoO2 /MoS2 @NSC) by controllable sulfidation. MoO2 and MoS2 are coupled intimately at atomic level, forming the MoO2 /MoS2 heterointerfaces with different distribution density. Strong electronic interactions are triggered at these MoO2 /MoS2 heterointerfaces for enhancing electron transfer. In alkaline media, the optimal material exhibits outstanding hydrogen evolution reaction (HER) performances that significantly surpass carbon-covered MoS2 nanorods counterpart (η10 : 156 mV vs 232 mV) and most of the MoS2 -based heterostructures reported recently. First-principles calculation deciphers that MoO2 /MoS2 heterointerfaces greatly promote water dissociation and hydrogen atom adsorption via the O-Mo-S electronic bridges during HER process. Moreover, benefited from the high pseudocapacitance contribution, abundant "ion reservoir"-like channels, and low Na+ diffusion barrier appended by high-density MoO2 /MoS2 heterointerfaces, the material delivers high specific capacity of 888 mAh g-1 , remarkable rate capability and cycling stability of 390 cycles at 0.1 A g-1 as the anode of sodium ion battery. This work will undoubtedly light the way of interface density engineering for high-performance electrochemical energy conversion and storage systems.

5.
Phys Chem Chem Phys ; 25(6): 4388-4407, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36723139

RESUMEN

Solar photocatalysis is the most ideal solution to global energy concerns and environmental deterioration nowadays. The heterojunction combination has become one of the most successful and effective strategies to design and manufacture composite photocatalysts. Heterojunction structures are widely documented to markedly improve the photocatalytic behavior of materials by enhancing the separation and transfer of photogenerated charges, widening the light absorption range, and broadening redox potentials, which are attributed to the presence of both build-in electric fields at the interface of two different materials and the complementarity between different electron structures. So far, a large number of heterojunction photocatalytic materials have been reported and applied for water splitting, reduction of carbon dioxide and nitrogen, environmental cleaning, etc. This review outlines the recent accomplishments in the design and modification of interface structures in heterojunction photocatalysts, aiming to provide some useful perspectives for future research in this field.

6.
Molecules ; 28(24)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38138503

RESUMEN

Visible-light-driven N2 reduction into NH3 in pure H2O provides an energy-saving alternative to the Haber-Bosch process for ammonia synthesizing. However, the thermodynamic stability of N≡N and low water solubility of N2 remain the key bottlenecks. Here, we propose a solution by developing a WO3-x hollow sphere with oxygen vacancies. Experimental analysis reveals that the hollow sphere structure greatly promotes the enrichment of N2 molecules in the inner cavity and facilitates the chemisorption of N2 onto WO3-x-HS. The outer layer's thin shell facilitates the photogenerated charge transfer and the full exposure of O vacancies as active sites. O vacancies exposed on the surface accelerate the activation of N≡N triple bonds. As such, the optimized catalyst shows a NH3 generation rate of 140.08 µmol g-1 h-1, which is 7.94 times higher than the counterpart WO3-bulk.

7.
Biochem Biophys Res Commun ; 611: 151-157, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35489201

RESUMEN

Macrophages play a crucial role in the pathogenesis of rheumatoid arthritis (RA) and have been considered as a therapeutic target of this disease. Here we show that mascRNA, a tRNA-like cytoplasmic small noncoding RNA, promoted RIPK1-dependent apoptosis (RDA) in RAW267.4 macrophages in response to the TAK1 inhibitor 5Z-7-oxozeaenol (5Z-7) alone as well as in combination with TNF. Moreover, mascRNA suppressed RANKL-induced expression of osteoclast marker genes and attenuated RANKL signaling. Using a murine model of collagen-induced arthritis (CIA), we demonstrated that mascRNA, administered either alone or in combination with 5Z-7, alleviated joint inflammation in CIA mice. Thus, mascRNA might be a promising agent for the treatment of RA.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Animales , Apoptosis , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/patología , Artritis Reumatoide/tratamiento farmacológico , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Inflamación/tratamiento farmacológico , Macrófagos/patología , Ratones , Osteoclastos/patología
8.
Phys Chem Chem Phys ; 25(1): 117-123, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36475462

RESUMEN

The enhancement of photogenerated carrier separation efficiency is a significant factor in the improvement of photocatalyst performance in photocatalytic hydrogen evolution. Heteroatom doping and defect construction have been considered valid methods to boost the photocatalytic activity of graphitic carbon nitride. Herein, we report graphitic carbon nitride modified with P doping and N defects (PCNx), and the effects of doping and defects were investigated in photocatalytic H2 evolution. Its hydrogen evolution rate can reach up to about 59.1 µmol h-1, which is more than 123.1 times higher than pristine graphitic carbon nitride under visible light irradiation. Importantly, the apparent quantum efficiency reaches 8.73% at 420 nm. The excellent performance of the PCNx photocatalyst was attributed to the following aspects: (I) the large BET surface area of PCNx affords more active sites for H2 production and (II) the introduction of P and N defects can accelerate the charge carrier separation and transfer efficiency, leading to more efficient photocatalytic hydrogen production. The photocatalyst showed obviously enhanced activities.

9.
Proc Natl Acad Sci U S A ; 116(21): 10232-10237, 2019 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-31064878

RESUMEN

Close proximity between different catalytic sites is crucial for accelerating or even enabling many important catalytic reactions. Photooxidation and photoreduction in photocatalysis are generally separated from each other, which arises from the hole-electron separation on photocatalyst surface. Here, we show with widely studied photocatalyst Pt/[Formula: see text] as a model, that concentrating abundant oxygen vacancies only at the metal-oxide interface can locate hole-driven oxidation sites in proximity to electron-driven reduction sites for triggering unusual reactions. Solar hydrogen production from aqueous-phase alcohols, whose hydrogen yield per photon is theoretically limited below 0.5 through conventional reactions, achieves an ultrahigh hydrogen yield per photon of 1.28 through the unusual reactions. We demonstrated that such defect engineering enables hole-driven CO oxidation at the Pt-[Formula: see text] interface to occur, which opens up room-temperature alcohol decomposition on Pt nanoparticles to [Formula: see text] and adsorbed CO, accompanying with electron-driven proton reduction on Pt to [Formula: see text].

10.
Toxicol Ind Health ; 38(7): 399-407, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35610186

RESUMEN

Cypermethrin, an extensively used pyrethroid pesticide, is regarded as one of many endocrine-disrupting chemicals (EDCs) with anti-androgenic activity to damage male reproductive systems. We previously found cypermethrin-induced apoptosis in mouse Sertoli cells TM4. We hypothesized cypermethrin-induced TM4 apoptosis by the endoplasmic reticulum (ER) pathway. This study aimed to explore the roles of the ER pathway in cypermethrin-induced apoptosis in TM4 cells. The cells were treated with cypermethrin for 24 h at various concentrations (0 µM, 10 µM, 20 µM, 40 µM, and 80 µM). Flow cytometry was used to test for apoptosis. Western blot was used to test protein expressions in the ER stress pathway. The results showed that the apoptosis rate of TM4 cells increased with increased concentrations of cypermethrin, and a significant difference was detected in the 80-µM group. The protein expressions of glucose-regulated protein 78 (GRP78), protein kinase R (PKR)-like ER kinase (PERK), p-PERK, α subunit of eukaryotic initiation factor (eIF2α), p-eIF2α, activating transcription factor 4 (ATF4), C/EBP homologous protein (CHOP), caspase-12, caspase-9, and caspase-3 increased with increased concentrations of cypermethrin. The results suggested cypermethrin-induced apoptosis in TM4 cells regulated by the ER pathway involving PERK-eIF2α-ATF4-CHOP. The study provides a new insight into cypermethrin-induced apoptosis in Sertoli cells.


Asunto(s)
Piretrinas , eIF-2 Quinasa , Factor de Transcripción Activador 4/metabolismo , Animales , Apoptosis , Retículo Endoplásmico , Factor 2 Eucariótico de Iniciación/metabolismo , Masculino , Ratones , Piretrinas/toxicidad , Células de Sertoli , Transducción de Señal , eIF-2 Quinasa/metabolismo
11.
Molecules ; 27(23)2022 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-36500637

RESUMEN

For achieving the goal of peaking carbon dioxide emissions and achieving carbon neutrality, developing hydrogen energy, the green and clean energy, shows a promising perspective for solving the energy and ecological issues. Herein, firstly, we used the hydrothermal method to synthesize the ZnS(en)0.5 as the precursor. Then, ZnS/ZnO composite was obtained by the in situ transformation of ZnS(en)0.5 with heat treatment under air atmosphere. The composition, optical property, morphology, and structural properties of the composite were characterized by X-ray photoemission spectroscopy (XPS), Ultraviolet-visible absorption spectra (Uv-vis Abs), Scanning electron microscopy (SEM) and Transmission electron microscopy image (TEM). Moreover, the content of ZnO in ZnS/ZnO was controlled via adjustment of the calcination times. The visible-light response of ZnS/ZnO originated from the in situ doping of N during the transformation of ZnS(en)0.5 to ZnS/ZnO under heat treatment, which was verified well by XPS. Photocatalytic hydrogen evolution experiments demonstrated that the sample of ZnS/ZnO-0.5 h with 6.9 wt% of ZnO had the best H2 evolution activity (1790 µmol/h/g) under visible light irradiation (λ > 400 nm), about 7.0 and 12.3 times that of the pure ZnS and ZnO, respectively. The enhanced activities of the ZnS/ZnO composites were ascribed to the intimated hetero-interface between components and efficient transfer of photo-generated electrons from ZnS to ZnO.


Asunto(s)
Hidrógeno , Luz , Catálisis , Espectroscopía de Fotoelectrones , Microscopía Electrónica de Transmisión , Hidrógeno/química
12.
Molecules ; 28(1)2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36615476

RESUMEN

New surface coordination photocatalytic systems that are inspired by natural photosynthesis have significant potential to boost fuel denitrification. Despite this, the direct synthesis of efficient surface coordination photocatalysts remains a major challenge. Herein, it is verified that a coordination photocatalyst can be constructed by coupling Pd and CTAB-modified ZnIn2S4 semiconductors. The optimized Pd/ZnIn2S4 showed a superior degradation rate of 81% for fuel denitrification within 240 min, which was 2.25 times higher than that of ZnIn2S4. From the in situ FTIR and XPS spectra of 1% Pd/ZnIn2S4 before and after pyridine adsorption, we find that pyridine can be selectively adsorbed and form Zn⋅⋅⋅C-N or In⋅⋅⋅C-N on the surface of Pd/ZnIn2S4. Meanwhile, the superior electrical conductivity of Pd can be combined with ZnIn2S4 to promote photocatalytic denitrification. This work also explains the surface/interface coordination effect of metal/nanosheets at the molecular level, playing an important role in photocatalytic fuel denitrification.


Asunto(s)
Desnitrificación , Piridinas , Adsorción , Conductividad Eléctrica , Fotosíntesis
13.
Anticancer Drugs ; 32(3): 248-256, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33534411

RESUMEN

Sesamin, a lignan compound, exhibits a variety of biological activities and possesses potent anticancer properties on some human cancers. However, its effect on human colorectal cancer (CRC) remains to be elucidated. To investigate the effects of sesamin on CRC cells and further to explore the mechanisms, cell viability, cell cycle and apoptosis assays were performed in this study. We found that sesamin had a selective antiproliferation of CRC cell line HCT116 in a dose- and time-dependent manner, but no obvious effect on human normal colorectal mucosa epithelial cell FHC. Further study showed that sesamin-induced cell cycle arrest and decreased the expression of Cyclin D1 significantly and dose-dependently in HCT116 cells. Moreover, sesamin dose-dependently triggered apoptosis of HCT116 but not FHC, and promoted the expression levels of proapoptotic biomarkers Bax, cleaved caspase-3 and cleaved PARP-1 and inhibited the expression of antiapoptotic biomarker Bcl-2. Western blot analysis was used to reveal the possible signaling pathways, and we found that sesamin upregulated the phosphorylation expression levels of C-Jun N-terminal kinase (JNK) and p38 except ERK1/2 in a dose-dependent way in both HCT116 and another CRC cell line SW480. Moreover, we found that the apoptosis effect induced by sesamin was partially eliminated by inhibiting JNK or p38 activation. Finally, we showed that sesamin effectively reduced the growth of xenograft tumors derived from cell lines with limited toxicity. Taken together, the potential ability of sesamin to induce cell cycle arrest and apoptosis was shown to be via the p38 and JNK mitogen-activated protein kinase signaling pathways, which may be one of the mechanisms of the anticancer activity of this low-toxic agent.


Asunto(s)
Antioxidantes/farmacología , Dioxoles/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/efectos de los fármacos , Lignanos/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular , Neoplasias Colorrectales , Ciclina D1/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Ratones , Ratones Endogámicos BALB C , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Regulación hacia Arriba , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
14.
Angew Chem Int Ed Engl ; 60(3): 1235-1243, 2021 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-33026673

RESUMEN

The design and synthesis of two semiconducting bis (4-ethynyl-bridging 1, 8-naphthalimide) bolaamphiphiles (BENI-COO- and BENI-NH3+ ) to fabricate supramolecular metal-insulator-semiconductor (MIS) nanostructures for biomimetic hydrogen evolution under visible light irradiation is presented. A H2 evolution rate of ca. 3.12 mmol g-1 ⋅h-1 and an apparent quantum efficiency (AQE) of ca. 1.63 % at 400 nm were achieved over the BENI-COO- -NH3+ -Ni MIS photosystem prepared by electrostatic self-assembly of BENI-COO- with the opposite-charged DuBois-Ni catalysts. The hot electrons of photoexcited BENI-COO- nanofibers were tunneled to the molecular Ni collectors across a salt bridge and an alkyl region of 2.2-2.5 nm length at a rate of 6.10×108  s-1 , which is five times larger than the BENI-NH3+ nanoribbons (1.17×108  s-1 ). The electric field benefited significantly the electron tunneling dynamics and compensated the charge-separated states insufficient in the BENI-COO- nanofibers.


Asunto(s)
Biomimética/métodos , Hidrógeno/química , Nanoestructuras/química , Naftalimidas/metabolismo , Electrones , Humanos
15.
Small ; 16(28): e2000040, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32519511

RESUMEN

Structures comprising high capacity active material are highly desirable in the development of advanced electrodes for energy storage devices. However, the structure degradation of such material still remains a challenge. The construction of amorphous and crystalline heterostructure appears to be a novel and effectual strategy to figure out the problem, owing to the distinct properties of the amorphous protective layer. Herein, crystalline-Co3 O4 @amorphous-TiO2 core-shell nanoarrays directly grown on the carbon cloth substrate are rationally designed to construct the free-standing electrode. In the unique structure, the 3D porous nanoarrays provide increased availability of electrochemical active sites, and the array with a unique heterostructure of crystalline Co3 O4 core and amorphous TiO2 shell exhibits intriguing synergistic properties. Besides, the amorphous TiO2 protective layer shows elastic behavior to mitigate the volume effect of Co3 O4 . Benefiting from these structural advantages, the as-prepared free-standing electrode exhibits superior lithium storage properties, including high coulombic efficiency, outstanding cyclic stability, and rate capability. Pouch cells with high flexibility are also fabricated and show remarkable electrochemical performances, holding great potential for flexible electronic devices in the future.

16.
J Exp Bot ; 71(12): 3512-3523, 2020 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-32507879

RESUMEN

In a previous study we identified EARLY BUD BREAK 1 (EBB1), an ERF transcription factor, in peach (Prunus persica var. nectarina cultivar Zhongyou 4); however, little is known of how PpEBB1 may regulate bud break. To verify the function of PpEBB1 in bud break, PpEBB1 was transiently transformed into peach buds, resulting in early bud break. Bud break occurred earlier in PpEBB1-oe poplar (Populus trichocarpa) obtained by heterologous transformation than in wild type (WT), consistent with the peach bud results, indicating that PpEBB1 can promote bud break. To explore how PpEBB1 affects bud break, differentially expressed genes (DEGs) between WT and PpEBB1-oe poplar plants were identified by RNA-sequencing. The expression of DEGs associated with hormone metabolism, cell cycle, and cell wall modifications changed substantially according to qRT-PCR. Auxin, ABA, and total trans-zeatin-type cytokinin levels were higher in the PpEBB1-oe plants than in WT plants, while the total N6-(Δ 2-isopentenyl)-adenine-type cytokinins was lower. Yeast two-hybrid and bimolecular fluorescence complementation assays verified that a cell wall modification-related protein (PpEXBL1) interacted with PpEBB1 suggesting that PpEBB1 could interact with these cell wall modification proteins directly. Overall, our study proposed a multifaceted explanation for how PpEBB1 regulates bud break and showed that PpEBB1 promotes bud break by regulating hormone metabolism, the cell cycle, and cell wall modifications.


Asunto(s)
Prunus persica , Ciclo Celular , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Hormonas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prunus persica/genética , Prunus persica/metabolismo
17.
J Exp Bot ; 71(4): 1585-1597, 2020 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-31740930

RESUMEN

The dormancy-associated MADS-box (DAM) genes PpDAM5 and PpDAM6 have been shown to play important roles in bud endodormancy; however, their molecular regulatory mechanism in peach is unclear. In this study, by use of yeast one-hybrid screening, we isolated a TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR transcription factor, PpTCP20, in the peach cultivar 'Zhongyou 4' (Prunus persica var. nectarina). The protein was localized in the nucleus and was capable of forming a homodimer. Electrophoretic mobility shift assays demonstrated that PpTCP20 binds to a GCCCR element in the promoters of PpDAM5 and PpDAM6, and transient dual luciferase experiments showed that PpTCP20 inhibited the expression of PpDAM5 and PpDAM6 as the period of the release of flower bud endodormancy approached. In addition, PpTCP20 interacted with PpABF2 to form heterodimers to regulate bud endodormancy, and the content of abscisic acid decreased with the release of endodormancy. PpTCP20 also inhibited expression of PpABF2 to regulate endodormancy. Taken together, our results suggest that PpTCP20 regulates peach flower bud endodormancy by negatively regulating the expression of PpDAM5 and PpDAM6, and by interacting with PpABF2, thus revealing a novel regulatory mechanism in a perennial deciduous tree.


Asunto(s)
Latencia en las Plantas , Proteínas de Plantas/fisiología , Prunus persica , Factores de Transcripción/fisiología , Ácido Abscísico , Regulación de la Expresión Génica de las Plantas , Regiones Promotoras Genéticas , Prunus persica/genética , Prunus persica/fisiología , Factores de Transcripción/genética
18.
Inorg Chem ; 59(2): 1566-1575, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31913603

RESUMEN

Photocatalytic hydrogen generation will benefit from the realization of more active but less expensive cocatalysts compared with noble metal counterparts. Herein we developed a universal vapor deposition method that selectively uses the thermal decomposition products of sodium hypophosphite as a phosphorus source for the fabrication of inexpensive and highly efficient metal phosphate (MPi) modified CdS nanorods. We find that the modification with a bimetal phosphate (i.e., 5 wt % NiCoPi) leads to an activity enhancement by a factor of approximately 52 in boosting visible-light-driven hydrogen evolution relative to the pristine CdS nanorods. The photocatalyst exhibits a high hydrogen generation rate of 13.44 mmol·g-1·h-1, which is much higher than that of its single metal counterparts (NiPi, 8.70 mmol·g-1·h-1; CoPi, 5.79 mmol·g-1·h-1) and 1 wt % Pt modified CdS (1.33 mmol·g-1·h-1). Its apparent quantum efficiency reaches 23.5% at 420 nm. Furthermore, it also shows remarkable photostability for eight consecutive cycles of photocatalytic activity tests with total reaction time of 24 h. The excellent photocatalytic performance of the photocatalyst is believed to be associated with the in situ formed NiICoP and NiCoIIIPi cocatalysts, which not only play an important role in photogenerated charge separation but also provide highly active catalytic reaction sites for the corresponding hydrogen evolution reaction and the sacrificial agent oxidation reaction.

19.
Angew Chem Int Ed Engl ; 59(47): 20919-20923, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-32783313

RESUMEN

It is a challenge to explore photocatalytic materials for sunlight-driven water splitting owing to the limited choice of a single semiconductor with suitable band energy levels but with a minimized band gap for light harvesting. Here, we report a one-photon excitation pathway by coupling polymeric carbon nitride (PCN) semiconductor with LaOCl to achieve overall water splitting. This artificial photosynthesis composite catalyzes the decomposition of H2 O into H2 and O2 , with evolution rates of 22.3 and 10.7 µmol h-1 , respectively. The high photocatalytic performance of PCN/LaOCl can be ascribed to the simultaneously accomplished reduction and oxidation of water on LaOCl and PCN domains, respectively, as well as the fast charge separation and migration induced by the interfacial electric field related to LaOCl modification. This study provides new insights on the development of composite photocatalysts for pure water splitting based on polymer-based materials via charge modulation.

20.
Environ Sci Technol ; 53(15): 9063-9072, 2019 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-31240913

RESUMEN

Our study on the synergetic effect of electrolysis and permanganate (E-PM) revealed a novel alternative method for generating active Mn(III)aq heterogeneously by electrochemically activating PM with Mn2+ as promoter and stabilizer. We systematically explored the generation mechanism of Mn(III)aq. It indicated that all three components (electrolysis + PM + Mn2+) were necessary to facilitate the generation of active Mn(III) in the E-PM-Mn2+ process. It was worth noting that Mn2+, as essential promoter and Mn(III)aq stabilizer, could considerably enhance the concentration of Mn(III) in the E-PM-Mn2+ process. Further study revealed that the active Mn(III) was mainly produced on cathode rather than in aqueous solution or on anode. In addition, the soluble Mn(III)aq generated in the E-PM-Mn2+ process was demonstrated to be very efficient for the degradation and mineralization of diclofenac (DCF) as well as methyl blue, carbamazepine, phenol, sulfamethoxazole, and nitrobenzene. Moreover, the effects of the main operating parameters (Mn2+ dosage, PM dosage, applied current density, pH of solution, and contaminant concentration) and different water matrices on the E-PM-Mn2+ process were investigated systematically. Possible degradation pathways of DCF in the E-PM-Mn2+ process were also proposed. The results demonstrated that the E-PM-Mn2+ system based on active Mn(III)aq could create a more efficient, sustainable, and less energy costing technology for water treatment.


Asunto(s)
Compuestos de Manganeso , Manganeso , Oxidación-Reducción , Óxidos
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