Search

Summary: Previous studies have reported that PID2, which encodes a B‐lectin receptor‐like kinase, is a key gene in the resistance of rice to Magnaporthe oryzae strain ZB15. However, the PID2‐mediated downstream signalling events remain largely unknown.The U‐box E3 ubiquitin ligase OsPIE3 (PID2‐interacting E3) was isolated and confirmed to play key roles in PID2‐mediated rice blast resistance. Yeast two‐hybrid analysis showed that the armadillo repeat region of OsPIE3 is required for its interaction with PID2. Further investigation demonstrated that OsPIE3 can modify the subcellular localisation of PID2, thus promoting its nuclear recruitment from the plasma membrane for protein degradation in the ubiquitin–proteasome system. Site‐directed mutagenesis of a conserved cysteine site (C230S) within the U‐box domain of OsPIE3 reduces PID2 translocation and ubiquitination.Genetic analysis suggested that OsPIE3 loss‐of‐function mutants exhibited enhanced resistance to M. oryzae isolate ZB15, whereas mutants with overexpressed OsPIE3 exhibited reduced resistance. Furthermore, the OsPIE3/PID2‐double mutant displayed a similar blast phenotype to that of the PID2 single mutant, suggesting that OsPIE3 is a negative regulator and functions along with PID2 in blast disease resistance.Our findings confirm that the E3 ubiquitin ligase OsPIE3 is necessary for PID2‐mediated rice blast disease resistance regulation. [ABSTRACT FROM AUTHOR]

Molecular catalysis is of great interest to CO2 photoreduction. Various transition metal complexes have been developed as efficient molecular catalysts. However, it remains a challenge to catalyze CO2 reduction by a small organic molecular photocatalyst, as the accumulation of multiple electrons in a small organic molecule is normally difficult for CO2 reduction. We report herein a small organic molecular catalyst can be used for selective reduction of CO2 to CO under visible light irradiation. The turnover number (TON) of CO formation is found to be 400±26 with near 100% selectivity in DMF/H2O medium. UV‐Vis absorption spectroscopy, density functional theory (DFT) calculations, and spectroelectrochemical studies demonstrate that the organic molecular catalyst is capable of accumulating electrons through a 2e− reduced product which shows good stability and is responsible for interacting with CO2. These findings elucidate an accessible way to develop purely organic molecular catalysts for CO2 reduction by strengthening the electron accumulation. [ABSTRACT FROM AUTHOR]

The consecutive photoinduced electron transfer (ConPET) process of 1,2,3,5-Tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) in CO2 photoreduction to achieve powerful reducing species has been disclosed by activating a bis(terpyridine)ruthenium(II) complex bearing a high overpotential for selective light-driven reduction of CO2 to CO in homogeneous solution. [ABSTRACT FROM AUTHOR]

A coordination nanosheet composed of [Fe(tpy)2]2+ (tpy = 2,2′:6′,2″-terpyridine) units, showing reversible electrochromism at the ligand-based cathodic potential, has been prepared through a liquid/liquid interfacial synthesis. The noble metal-free nanosheet exhibited a CO evolution rate of 114.3 mmol·g−1·h−1 with the selectivity up to 99.3% under visible light irradiation in the presence of water, which is in the front rank of heterogeneous catalysis for CO2 photoreduction. Such robust photocatalytic performance is due to efficient ligand-based electron transfer through long-lived π radical anion tpy− with a lifetime more than 25 min, as evidenced by in situ electron paramagnetic resonance (EPR) and ultraviolet—visible—near infrared (UV—vis—NIR) spectroscopy studies. Fe(II) cation in [Fe(tpy)2]2+ mainly contributes to enhancing reduction potentials of ligand and stabilizing π radical anion tpy−. This ligand-based electron transfer with the aid of metal cation represents a promising strategy for selective CO2 photoreduction, especially towards gaining CO from CO2. [ABSTRACT FROM AUTHOR]

A discrete metallo-supramolecular assembly composed of six iron(II) cations and twelve redox-active terpyridine fragments has been developed for the highly efficient visible-light-driven reduction of CO2 to CO with a TON of 14 956 and 99.6% selectivity in the presence of an organic thermally activated delayed fluorescence (TADF) photosensitizer 4CzIPN in aqueous solution. The photochemical system proceeds rapidly with a turnover frequency (TOF) of 276 min−1. It is demonstrated that the redox-active terpyridine fragments in the assembly are reduced by the photosensitizer which could further act as an electron reservoir for CO2 reduction, resulting in the highly efficient reduction of CO2. This work shows that discrete metallo-supramolecular assemblies could be used for robust photochemical CO2 reduction. [ABSTRACT FROM AUTHOR]

Microsporidia are obligate intracellular parasites, existing in a wide variety of animal hosts. Here, we reported Aloc SWP2, a novel protein identified from the spore wall of Antonospora locustae (formerly, Nosema locustae, and synonym, Paranosema locustae), containing four cysteines that are conserved among the homologues of several Microspodian pathogens in insects and mammals. Aloc SWP2 was detected in the wall of mature spores via indirect immunofluorescence assay. In addition, immunocytochemistry localization experiments showed that the protein was observed in the wall of sporoblasts, sporonts, and meronts during sporulation within the host body, also in the wall of mature spores. Aloc SWP2 was not detected in the fat body of infected locust until the 9th day after inoculating spores via RT- PCR experiments. Furthermore, the survival percentage of infected locusts injected with ds RNA of Aloc SWP2 on the 15th, 16th, and 17th days after inoculation with microsporidian were significantly higher than those of infected locusts without ds RNA treatment. Conversely, the amount of spores in locusts infected with A. locustae after treated with RNAi Aloc SWP2 was significantly lower than those of infected locusts without RNAi of this gene. This novel spore wall protein from A. locustae may be involved in sporulation, thus contributing to host mortality. [ABSTRACT FROM AUTHOR]

Molecular catalysis is of great interest to CO 2 photoreduction. Various transition metal complexes have been developed as efficient molecular catalysts. However, it remains a challenge to catalyze CO 2 reduction by a small organic molecular photocatalyst, as the accumulation of multiple electrons in a small organic molecule is normally difficult for CO 2 reduction. We report herein a small organic molecular catalyst can be used for selective reduction of CO 2 to CO under visible light irradiation. The turnover number (TON) of CO formation is found to be 400±26 with near 100% selectivity in DMF/H 2 O medium. UV-Vis absorption spectroscopy, density functional theory (DFT) calculations, and spectroelectrochemical studies demonstrate that the organic molecular catalyst is capable of accumulating electrons through a 2e - reduced product which shows good stability and is responsible for interacting with CO 2 . These findings elucidate an accessible way to develop purely organic molecular catalysts for CO 2 reduction by strengthening the electron accumulation., (© 2022 Wiley-VCH GmbH.)

The consecutive photoinduced electron transfer (ConPET) process of 1,2,3,5-Tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) in CO 2 photoreduction to achieve powerful reducing species has been disclosed by activating a bis(terpyridine)ruthenium(II) complex bearing a high overpotential for selective light-driven reduction of CO 2 to CO in homogeneous solution.

A discrete metallo-supramolecular assembly composed of six iron(ii) cations and twelve redox-active terpyridine fragments has been developed for the highly efficient visible-light-driven reduction of CO2 to CO with a TON of 14 956 and 99.6% selectivity in the presence of an organic thermally activated delayed fluorescence (TADF) photosensitizer 4CzIPN in aqueous solution. The photochemical system proceeds rapidly with a turnover frequency (TOF) of 276 min-1. It is demonstrated that the redox-active terpyridine fragments in the assembly are reduced by the photosensitizer which could further act as an electron reservoir for CO2 reduction, resulting in the highly efficient reduction of CO2. This work shows that discrete metallo-supramolecular assemblies could be used for robust photochemical CO2 reduction.

Photocatalytic CO 2 reduction reaction is believed to be a promising approach for CO 2 utilization. In this work, a noble metal-free photocatalytic system, composed of bis (terpyridine)iron(II) complexes and an organic thermally activated delayed fluorescence compound, has been developed for selective reduction of CO 2 to CO with a maximum turnover number up to 6320, 99.4% selectivity, and turnover frequency of 127 min -1 under visible-light irradiation in dimethylformamide/H 2 O solution. More than 0.3 mmol CO was generated using 0.05 μmol catalyst after 2 h of light irradiation. The apparent quantum yield was found to be 9.5% at 440 nm (180 mW cm -2 ). Control experiments and UV-vis-NIR spectroscopy studies further demonstrated that water strongly promoted the photocatalytic cycle and terpyridine ligands rather than Fe(II) were initially reduced during the photocatalytic process.

In order to clarify the regulation of granule cell stimulating factor (GCSF) on granulosa cells, we studied the effect of GCSF on proliferation and apoptosis of in vitro cultured granulosa cells for research on GCSF used in sheep reproduction and breeding. Sheep GCSF protein was prokaryotic expressed and purified. Its bio-activity was measured with M-NSF60 cells. The purified GCSF was added in cell culture medium in experiment groups with non-added as control. Alarmarblue was used to measure cell proliferation, and flow cytometry was used to detect cell cycles and apoptosis. Sheep GCSF could be expressed and purified. Cell activity increased with GCSF concentration from 0.06 to 600 ng/mL at 24 h and 48 h. Cell cycles were significantly different between experiment and control groups at 24 h. Cell ratio of S was significantly reduced (P<0.05) and G2/M phase significantly increased (P<0.05). The apoptosis ratio of experiment group was significantly reduced (P<0.05) at 48 h. In conclusion, GCSF could enhance cell proliferation, inhibit apoptosis, and regulate cell cycles on in vitro cultured sheep granulosa cells.

Epithelial-Mesenchymal Transition (EMT) is a critical step in the progression of cancer. Malignant melanoma, a cancer developed from pigmented melanocytes, metastasizes through an EMT-like process. Ten-eleven translocation (TET) enzymes, catalyzing the conversion of 5-methylcytosine (5mC) to 5-hydroxylmethylcytosine (5-hmC), are down regulated in melanoma. However, their roles in the progression and the EMT-like process of melanoma are not fully understood. Here we report that DNA methylation induced silencing of TET2 and TET3 are responsible for the EMT-like process and the metastasis of melanoma. TET2 and TET3 are down regulated in the TGF-β1-induced EMT-like process, and the knocking down of TET2 or TET3 induced this EMT-like process. A DNA demethylating agent antagonized the TGF-β-induced suppression of TET2 and TET3. Furthermore, a ChIP analysis indicated that enhanced recruitment of DNMT3A (DNA Methyltransferase 3A) is the mechanism by which TGF-β induces the silencing of TET2 and TET3. Finally, the overexpression of the TET2 C-terminal sequence partially rescues the TGF-β1-induced EMT-like process in vitro and inhibits tumor growth and metastasis in vivo. Hence, our data suggest an epigenetic circuitry that mediates the EMT activated by TGF-β. As an effector, DNMT3A senses the TGF-β signal and silences TET2 and TET3 promoters to induce the EMT-like process and metastasis in melanoma.