The Experts below are selected from a list of 189711 Experts worldwide ranked by ideXlab platform
Jun Minagawa - One of the best experts on this subject based on the ideXlab platform.
-
algal photoprotection is regulated by the e3 ligase cul4 ddb1 det1
2019Co-Authors: Tomohito Yamasaki, Jun Minagawa, Yusuke Aihara, Konomi FujimurakamadaAbstract:Light is essential for photosynthesis, but the amounts of light that exceed an organism’s assimilation capacity can cause serious damage1. Photosynthetic organisms minimize such potential harm through protection mechanisms collectively referred to as non-photochemical Quenching2. One mechanism of non-photochemical Quenching called energy-dependent Quenching (qE Quenching) is readily activated under high-light conditions and dissipates excess energy as heat. LIGHT-HARVESTING COMPLEX STRESS-RELATED PROTEINS 1 and 3 (LHCSR1 and LHCSR3) have been proposed to mediate qE Quenching in the green alga Chlamydomonas reinhardtii when grown under high-light conditions3. LHCSR3 induction requires a blue-light photoreceptor, PHOTOTROPIN (PHOT)4, although the signal transduction pathway between PHOT and LHCSR3 is not yet clear. Here, we identify two phot suppressor loci involved in qE Quenching: de-etiolated 1 (det1)5 and damaged DNA-binding 1 (ddb1)6. Using a yeast two-hybrid analysis and an inhibitor assay, we determined that these two genetic elements are part of a protein complex containing CULLIN 4 (CUL4). These findings suggest a photoprotective role for the putative E3 ubiquitin ligase CUL4–DDB1DET1 in unicellular photosynthetic organisms that may mediate blue-light signals to LHCSR1 and LHCSR3 gene expression. Photosynthetic organisms minimize potential harm from excess light by protection mechanisms collectively referred to as non-photochemical Quenching. Two proteins involved in Quenching, DAMAGED DNA-BINDING 1 and DE-ETIOLATED 1, are part of a complex containing CULLIN 4.
-
algal photoprotection is regulated by the e3 ligase cul4 ddb1 det1
2019Co-Authors: Tomohito Yamasaki, Jun Minagawa, Yusuke Aihara, Konomi FujimurakamadaAbstract:Light is essential for photosynthesis, but the amounts of light that exceed an organism's assimilation capacity can cause serious damage1. Photosynthetic organisms minimize such potential harm through protection mechanisms collectively referred to as non-photochemical Quenching2. One mechanism of non-photochemical Quenching called energy-dependent Quenching (qE Quenching) is readily activated under high-light conditions and dissipates excess energy as heat. LIGHT-HARVESTING COMPLEX STRESS-RELATED PROTEINS 1 and 3 (LHCSR1 and LHCSR3) have been proposed to mediate qE Quenching in the green alga Chlamydomonas reinhardtii when grown under high-light conditions3. LHCSR3 induction requires a blue-light photoreceptor, PHOTOTROPIN (PHOT)4, although the signal transduction pathway between PHOT and LHCSR3 is not yet clear. Here, we identify two phot suppressor loci involved in qE Quenching: de-etiolated 1 (det1)5 and damaged DNA-binding 1 (ddb1)6. Using a yeast two-hybrid analysis and an inhibitor assay, we determined that these two genetic elements are part of a protein complex containing CULLIN 4 (CUL4). These findings suggest a photoprotective role for the putative E3 ubiquitin ligase CUL4-DDB1DET1 in unicellular photosynthetic organisms that may mediate blue-light signals to LHCSR1 and LHCSR3 gene expression.
Yusuke Aihara - One of the best experts on this subject based on the ideXlab platform.
-
algal photoprotection is regulated by the e3 ligase cul4 ddb1 det1
2019Co-Authors: Tomohito Yamasaki, Jun Minagawa, Yusuke Aihara, Konomi FujimurakamadaAbstract:Light is essential for photosynthesis, but the amounts of light that exceed an organism’s assimilation capacity can cause serious damage1. Photosynthetic organisms minimize such potential harm through protection mechanisms collectively referred to as non-photochemical Quenching2. One mechanism of non-photochemical Quenching called energy-dependent Quenching (qE Quenching) is readily activated under high-light conditions and dissipates excess energy as heat. LIGHT-HARVESTING COMPLEX STRESS-RELATED PROTEINS 1 and 3 (LHCSR1 and LHCSR3) have been proposed to mediate qE Quenching in the green alga Chlamydomonas reinhardtii when grown under high-light conditions3. LHCSR3 induction requires a blue-light photoreceptor, PHOTOTROPIN (PHOT)4, although the signal transduction pathway between PHOT and LHCSR3 is not yet clear. Here, we identify two phot suppressor loci involved in qE Quenching: de-etiolated 1 (det1)5 and damaged DNA-binding 1 (ddb1)6. Using a yeast two-hybrid analysis and an inhibitor assay, we determined that these two genetic elements are part of a protein complex containing CULLIN 4 (CUL4). These findings suggest a photoprotective role for the putative E3 ubiquitin ligase CUL4–DDB1DET1 in unicellular photosynthetic organisms that may mediate blue-light signals to LHCSR1 and LHCSR3 gene expression. Photosynthetic organisms minimize potential harm from excess light by protection mechanisms collectively referred to as non-photochemical Quenching. Two proteins involved in Quenching, DAMAGED DNA-BINDING 1 and DE-ETIOLATED 1, are part of a complex containing CULLIN 4.
-
algal photoprotection is regulated by the e3 ligase cul4 ddb1 det1
2019Co-Authors: Tomohito Yamasaki, Jun Minagawa, Yusuke Aihara, Konomi FujimurakamadaAbstract:Light is essential for photosynthesis, but the amounts of light that exceed an organism's assimilation capacity can cause serious damage1. Photosynthetic organisms minimize such potential harm through protection mechanisms collectively referred to as non-photochemical Quenching2. One mechanism of non-photochemical Quenching called energy-dependent Quenching (qE Quenching) is readily activated under high-light conditions and dissipates excess energy as heat. LIGHT-HARVESTING COMPLEX STRESS-RELATED PROTEINS 1 and 3 (LHCSR1 and LHCSR3) have been proposed to mediate qE Quenching in the green alga Chlamydomonas reinhardtii when grown under high-light conditions3. LHCSR3 induction requires a blue-light photoreceptor, PHOTOTROPIN (PHOT)4, although the signal transduction pathway between PHOT and LHCSR3 is not yet clear. Here, we identify two phot suppressor loci involved in qE Quenching: de-etiolated 1 (det1)5 and damaged DNA-binding 1 (ddb1)6. Using a yeast two-hybrid analysis and an inhibitor assay, we determined that these two genetic elements are part of a protein complex containing CULLIN 4 (CUL4). These findings suggest a photoprotective role for the putative E3 ubiquitin ligase CUL4-DDB1DET1 in unicellular photosynthetic organisms that may mediate blue-light signals to LHCSR1 and LHCSR3 gene expression.
Tomohito Yamasaki - One of the best experts on this subject based on the ideXlab platform.
-
algal photoprotection is regulated by the e3 ligase cul4 ddb1 det1
2019Co-Authors: Tomohito Yamasaki, Jun Minagawa, Yusuke Aihara, Konomi FujimurakamadaAbstract:Light is essential for photosynthesis, but the amounts of light that exceed an organism’s assimilation capacity can cause serious damage1. Photosynthetic organisms minimize such potential harm through protection mechanisms collectively referred to as non-photochemical Quenching2. One mechanism of non-photochemical Quenching called energy-dependent Quenching (qE Quenching) is readily activated under high-light conditions and dissipates excess energy as heat. LIGHT-HARVESTING COMPLEX STRESS-RELATED PROTEINS 1 and 3 (LHCSR1 and LHCSR3) have been proposed to mediate qE Quenching in the green alga Chlamydomonas reinhardtii when grown under high-light conditions3. LHCSR3 induction requires a blue-light photoreceptor, PHOTOTROPIN (PHOT)4, although the signal transduction pathway between PHOT and LHCSR3 is not yet clear. Here, we identify two phot suppressor loci involved in qE Quenching: de-etiolated 1 (det1)5 and damaged DNA-binding 1 (ddb1)6. Using a yeast two-hybrid analysis and an inhibitor assay, we determined that these two genetic elements are part of a protein complex containing CULLIN 4 (CUL4). These findings suggest a photoprotective role for the putative E3 ubiquitin ligase CUL4–DDB1DET1 in unicellular photosynthetic organisms that may mediate blue-light signals to LHCSR1 and LHCSR3 gene expression. Photosynthetic organisms minimize potential harm from excess light by protection mechanisms collectively referred to as non-photochemical Quenching. Two proteins involved in Quenching, DAMAGED DNA-BINDING 1 and DE-ETIOLATED 1, are part of a complex containing CULLIN 4.
-
algal photoprotection is regulated by the e3 ligase cul4 ddb1 det1
2019Co-Authors: Tomohito Yamasaki, Jun Minagawa, Yusuke Aihara, Konomi FujimurakamadaAbstract:Light is essential for photosynthesis, but the amounts of light that exceed an organism's assimilation capacity can cause serious damage1. Photosynthetic organisms minimize such potential harm through protection mechanisms collectively referred to as non-photochemical Quenching2. One mechanism of non-photochemical Quenching called energy-dependent Quenching (qE Quenching) is readily activated under high-light conditions and dissipates excess energy as heat. LIGHT-HARVESTING COMPLEX STRESS-RELATED PROTEINS 1 and 3 (LHCSR1 and LHCSR3) have been proposed to mediate qE Quenching in the green alga Chlamydomonas reinhardtii when grown under high-light conditions3. LHCSR3 induction requires a blue-light photoreceptor, PHOTOTROPIN (PHOT)4, although the signal transduction pathway between PHOT and LHCSR3 is not yet clear. Here, we identify two phot suppressor loci involved in qE Quenching: de-etiolated 1 (det1)5 and damaged DNA-binding 1 (ddb1)6. Using a yeast two-hybrid analysis and an inhibitor assay, we determined that these two genetic elements are part of a protein complex containing CULLIN 4 (CUL4). These findings suggest a photoprotective role for the putative E3 ubiquitin ligase CUL4-DDB1DET1 in unicellular photosynthetic organisms that may mediate blue-light signals to LHCSR1 and LHCSR3 gene expression.
Andries Meijerink - One of the best experts on this subject based on the ideXlab platform.
-
Quenching of the red mn4 luminescence in mn4 doped fluoride led phosphors
2018Co-Authors: Tim Senden, Relinde J A Van Dijkmoes, Andries MeijerinkAbstract:Red-emitting Mn4+-doped fluorides are a promising class of materials to improve the color rendering and luminous efficacy of white light-emitting diodes (w-LEDs). For w-LEDs, the luminescence Quenching temperature is very important, but surprisingly no systematic research has been conducted to understand the mechanism for thermal Quenching in Mn4+-doped fluorides. Furthermore, concentration Quenching of the Mn4+ luminescence can be an issue but detailed investigations are lacking. In this work, we study thermal Quenching and concentration Quenching in Mn4+-doped fluorides by measuring luminescence spectra and decay curves of K2TiF6:Mn4+ between 4 and 600 K and for Mn4+ concentrations from 0.01% to 15.7%. Temperature-dependent measurements on K2TiF6:Mn4+ and other Mn4+-doped phosphors show that Quenching occurs through thermally activated crossover between the 4T2 excited state and 4A2 ground state. The Quenching temperature can be optimized by designing host lattices in which Mn4+ has a high 4T2 state energy. Concentration-dependent studies reveal that concentration Quenching effects are limited in K2TiF6:Mn4+ up to 5% Mn4+. This is important, as high Mn4+ concentrations are required for sufficient absorption of blue LED light in the parity-forbidden Mn4+ d-d transitions. At even higher Mn4+ concentrations (>10%), the quantum efficiency decreases, mostly due to direct energy transfer to Quenching sites (defects and impurity ions). Optimization of the synthesis to reduce quenchers is crucial for developing more efficient highly absorbing Mn4+ phosphors. The present systematic study provides detailed insights into temperature and concentration Quenching of Mn4+ emission and can be used to realize superior narrow-band red Mn4+ phosphors for w-LEDs.
-
insight into the thermal Quenching mechanism for y3al5o12 ce3 through thermoluminescence excitation spectroscopy
2015Co-Authors: Jumpei Ueda, Andries Meijerink, P Dorenbos, Setsuhisa TanabeAbstract:Y3Al5O12(YAG):Ce3+ is the most widely applied phosphor in white LEDs (w-LEDs) because of strong blue absorption and efficient yellow luminescence combined with a high stability and thermal Quenching temperature, required for the extreme operating conditions in high-power w-LEDs. The high luminescence Quenching temperature (∼600 K) has been well established, but surprisingly, the mechanism for temperature Quenching has not been elucidated yet. In this report we investigate the possibility of thermal ionization as a cause of this Quenching process by measuring thermoluminescence (TL) excitation spectra at various temperatures. In the TL excitation (TLE) spectrum at room temperature there is no Ce3+:5d1 band (the lowest excited 5d level). However, in the TLE spectrum at 573 K, which corresponds to the onset temperature of luminescence Quenching, a TLE band due to the Ce3+:5d1 excitation was observed at around 450 nm. On the basis of our observations we conclude that the luminescence Quenching of YAG:Ce3+ at ...
-
high temperature luminescence Quenching of colloidal quantum dots
2012Co-Authors: Yiming Zhao, Charl F Riemersma, Francesca Pietra, Rolf Koole, Celso De Mello Donega, Andries MeijerinkAbstract:Thermal Quenching of quantum dot (QD) luminescence is important for application in luminescent devices. Systematic studies of the Quenching behavior above 300 K are, however, lacking. Here, high-temperature (300–500 K) luminescence studies are reported for highly efficient CdSe core–shell quantum dots (QDs), aimed at obtaining insight into temperature Quenching of QD emission. Through thermal cycling (yoyo) experiments for QDs in polymer matrices, reversible and irreversible luminescence Quenching processes can be distinguished. For a variety of core–shell systems, reversible Quenching is observed in a similar temperature range, between 100 and 180 °C. The irreversible Quenching behavior varies between different systems. Mechanisms for thermal Quenching are discussed.
-
temperature Quenching of yellow ce3 luminescence in yag ce
2009Co-Authors: Volker Bachmann, Cees Ronda, Andries MeijerinkAbstract:Yttrium aluminum garnet (YAG) doped with Ce3+ is the phosphor of choice for the conversion of blue to yellow light in the rapidly expanding market of white light LEDs, but it is generally thought to suffer from a low luminescence Quenching temperature. The luminescence Quenching temperature is an important parameter, especially in high-power LEDs, but surprisingly no systematic research has been done to measure and understand the temperature Quenching of the yellow Ce luminescence in YAG:Ce. Here we report on the luminescence temperature Quenching in YAG:Ce. For a wide range of Ce concentrations (between 0.033% and 3.3%) the temperature dependence of the emission intensity and the luminescence lifetimes are reported. The intrinsic Quenching temperature of the Ce luminescence is shown to be very high (>700 K). The lower Quenching temperatures reported in the literature are explained by thermally activated concentration Quenching (for highly doped systems) and the temperature dependence of the oscillator st...
Sharmistha Dutta Choudhury - One of the best experts on this subject based on the ideXlab platform.
-
photophysics and luminescence Quenching of carbon dots derived from lemon juice and glycerol
2019Co-Authors: Poojan Milan Gharat, Haridas Pal, Sharmistha Dutta ChoudhuryAbstract:During the past decade, carbon dots have emerged as a fascinating class of luminescent nanomaterials with versatile application potentials in bioimaging, labeling, photocatalysis and optoelectronics. Currently, intensive research is concentrated on understanding the intriguing optical properties of these promising materials and their utility as luminescence sensors. In this article, we describe the photoluminescence of carbon dots obtained from a bioresource (lemon juice) and from a small molecule precursor (glycerol), especially the Quenching of their emission by nitrobenzene and Hg2+ ions, as representative cases. Stern-Volmer analysis using steady-state and time-resolved emission measurements, suggests the involvement of both transient Quenching and dynamic Quenching mechanisms in the interaction of the carbon dots with nitrobenzene. The radius of the Quenching sphere is estimated to be slightly greater than the contact distances between the respective carbon dots and nitrobenzene, which is in reasonable agreement with the "sphere of action" model for transient Quenching. In the interaction with Hg2+ ions, electrostatic attraction plays a major role, and the Quenching mechanism involves predominantly static and dynamic Quenching. The static Quenching constant matches well with the binding constant of the carbon dots with the metal ion.
