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Ethylene and Cytokinin:Partners in Root Growth Regulation

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Molecular Plant 2019年第10期12卷 1312-1314页

作者： Christina Artner eva Benkova Institute of Science and Technology Austria Am Campus 1KlosterneuburgAustria

Ethylene and cytokinin,two plant hormones with essential functions throughout the plant's life cycle,contribute to a wide spectrum of physiological,biochemical,and developmental *** the last decades,the molecular mechanisms underlying their biosynthesis and metabolism as well as pathways mediating their perception and signal transduction have been *** machineries controlling the activities of these two central hormonal regulators appear robust and autonomous,in the ever-changing environmental conditions that plants face,survival is dependent on their tight communication and mutually balanced activities.A recent work by Zdarska et al.(2019)is trying to address the challenging question regarding the mechanisms underlying the cytokinin and ethylene *** study reveals an intriguing,multilayered nature of hormonal interaction,in which the EHYLENE RESISTANT 1(ETR1)receptor upon perceiving an ethylene signal activates a multistep phosphorelay(MSP)cytokinin transduction cascade,integrating ethylene and cytokinin in the control of root apical meristem *** parallel,activation of canonical ethylene signaling adjusts the responsiveness of the cytokinin pathway by transcriptional upregulation of one of its key signaling components,the ARR10 response regulator(Figure 1).Importantly,unlike the canonical ethylene transduction machinery,ethylene input into the MSP is dependent on histidine kinase activity of ETR1 receptor.

关键词： Ethylene Root metabolism

MINIMIZING EXCITATION LIGHT LEAKAGE AND MAXIMIZING MEASUREMENT SENSITIVITY FOR MOLECULAR IMAGING WITH NEAR-INFRARED FLUORESCENCE

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Journal of Innovative Optical Health Sciences 2011年第3期4卷 301-307页

作者： BANGHE ZHU eva M.SEVICK-MURACA Center for Molecular Imaging The Brown Foundation Institute of Molecular Medicine The University of Texas Health Science Center at Houston Houston TX 77030USA

Near-infraredfluorescence(NIRF)imaging involves the separation of weakfluorescence signals from backscattered excitation *** measurement sensitivity of current NIRF imaging systems is limited by the excitation light leakage through *** this contribution,the authors demonstrate that the excitation light leakage can be suppressed upon using appropriatefilter combination and *** excitation light leakage and measurement sensitivity were assessed and compared in this study by computing the transmission ratios of excitation to emission light collected and the signal-to-noise ratios in well-controlled phantom studies with differentfilter combinations and *** appropriatefilter combinations and permutations,we observe as much as two orders of magnitude reduction in the transmission ratio and higher signal-to-noise ratio.

关键词： Molecular imaging fluorescence opticalfilter excitation light leakage noise floor

The many faces of cGAS:how cGAS activation is controlled in the cytosol,the nucleus,and during mitosis

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Signal Transduction and Targeted Therapy 2021年第8期6卷 2261-2263页

作者： Anna-Maria Herzner Martin Schlee eva Bartok Department of Cancer Immunology and Immune Modulation Boehringer Ingelheim Pharma GmbH&Co.KGBiberach an der RiBGermany lnstitute of Clinical Chemistry and Clinical Pharmacology University HospitalUniversity of BonnBonnGermany Unit of Experimental Immunology Department of Biomedical SciencesInstitute of Tropical MedicineAntwerpBelgium

In their recently published study in Science,Li et al.1 unravel how hyperphosphorylation and chromatin-tethering of the double-stranded(dsDNA)sensor cGAMP synthase(cGAS)prevent self DNA recognition during mitosis(Fig.1);providing important insight into how this innate immune sensor balances its essential function for pathogen defense against potential autoinflammation.

关键词： activation sensor insight

Subcellular Distribution of Glutathione Precursors in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2011年第12期53卷 930-941页

作者： Barbara eva Koffler Romana Maier Bernd Zechmann University of Graz Institute of Plant Sciences 8010 Graz Austria Graz University of Technology Institute for Electron Microscopy and Fine Structure Research 8010 Graz Austria

Glutathione is an important antioxidant and has many important functions in plant development, growth and defense. Glutathione synthesis and degradation is highly compartment-specific and relies on the subcellular availability of its precursors, cysteine, glutamate, glycine and γ-glutamylcysteine especially in plastids and the cytosol which are considered as the main centers for glutathione synthesis. The availability of glutathione precursors within these cell compartments is therefore of great importance for successful plant development and defense. The aim of this study was to investigate the compartmentspecific importance of glutathione precursors in Arabidopsis thaliana. The subcellular distribution was compared between wild type plants （Col-0）, plants with impaired glutathione synthesis （glutathione deficient pad2-1 mutant, wild type plants treated with buthionine sulfoximine）, and one complemented line （OE3） with restored glutathione synthesis. Immunocytohistochemistry revealed that the inhibition of glutathione synthesis induced the accumulation of the glutathione precursors cysteine, glutamate and glycine in most cell compartments including plastids and the cytosol. A strong decrease could be observed in γ-glutamylcysteine （γ-EC） contents in these cell compartments. These experiments demonstrated that the inhibition of γ-glutamylcysteine synthetase （GSH1） - the first enzyme of glutathione synthesis - causes a reduction of γ-EC levels and an accumulation of all other glutathione precursors within the cells.

关键词： Arabidopsis cysteine glutamate glutathione glycine.

Towards Characterization of the Chloroplast NAD（P）H Dehydrogenase Complex

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Molecular Plant 2009年第6期2卷 1127-1140页

作者： Marjaana Suorsa Sari Sirpio eva-Mari Aro Department of Biology Plant Physiology and Molecular Biology University of Turku FI-20014 Turku Finland

The NAD（P）H dehydrogenase （NDH） complex in chloroplast thylakoid membranes functions in cyclic electron transfer, and in chlororespiration. NDH is composed of at least 15 subunits, including both chloroplast- and nuclear-encoded proteins. During the past few years, extensive proteomic and genetic research on the higher plant NDH complex has been carried out, resulting in identification of several novel nuclear-encoded subunits. In addition, a number of auxiliary proteins, which mainly regulate the expression of chloroplast-encoded ndh genes as well as the assembly and stabilization of the NDH complex, have been discovered and characterized. In the absence of detailed crystallographic data, the structure of the NDH complex has remained obscure, and therefore the role of several NDH-associated nuclear-encoded proteins either as auxiliary proteins or structural subunits remains uncertain. In this review, we summarize the current knowledge on the subunit composition and assembly process of the chloroplast NDH complex. In addition, a novel oligomeric structure of NDH, the PSI/NDH supercomplex, is discussed.

关键词： Arabidopsis maize tobacco NAD(P)H dehydrogenese chloroplast thylakoid membrane cyclic electron transfer photosystem I.

Magnetic modification of diamagnetic agglomerate forming powder materials

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Particuology 2016年第6期14卷 169-171页

作者： Ivo Safarik eva Baldikova Kristyna Pospiskova Mirka Safarikova Department of Nanobiotechnology Biology Centre ISB CAS Na Sadkach 7 370 05 Ceske Budejovice Czech Republic Regional Centre of Advanced Technologies and Materials Palacky University Slechtitelu 27 783 71 Olomouc Czech Republic Global Change Research Institute CAS Na Sadkach 7 370 05 Ceske Budejovice Czech Republic Department of Applied Chemistry Faculty of Agriculture University of South Bohemia Branisovska 1457 370 05 Ceske Budejovice Czech Republic

A simple method for the magnetic modification of various types of powdered agglomerate forming dia- magnetic materials was developed. Magnetic iron oxide particles were prepared from ferrous sulfate by microwave assisted synthesis. A suspension of the magnetic particles in water soluble organic solvent （methanol, ethanol, propanol, isopropyl alcohol, or acetone） was mixed with the material to be modified and then completely dried at elevated temperature. The magnetically modified materials were found to be stable in water suspension at least for 2 months.

关键词： Magnetic modification Magnetic separation Powdered material Magnetic iron oxide Microwave assisted synthesis

Gromov Hyperbolicity of Riemann Surfaces

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Acta Mathematica Sinica,English Series 2007年第2期23卷 209-228页

作者： José M.RODRíGUEZ eva TOURIS Departamento de Matemáticas Universidad Carlos Ⅲ de MadridAvenida de la Universidad 3028911 LeganésMadridSpain

We study the hyperbolicity in the Gromov sense of Riemann surfaces. We deduce the hyperbolicity of a surface from the hyperbolicity of its ＂building block components＂. We also prove the equivalence between the hyperbolicity of a Riemann surface and the hyperbolicity of some graph associated with it. These results clarify how the decomposition of a Riemann surface into Y-pieces and funnels affects the hyperbolicity of the surface. The results simplify the topology of the surface and allow us to obtain global results from local information.

关键词： Gromov hyperbolicity hyperbolic Riemann surface

Are genetically distinct lizard species able to hybridize？ A review

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Current Zoology 2015年第1期61卷 155-180页

作者： Jitka JANCUCHOVA-LASKOVA eva LANDOVA Daniel FRYNTA Department of Zoology Faculty of Science Charles University Vini6n~t 7 CZ-128 44 Prague Czech Republic

Animal species are delimited by reproductive isolation mechanisms （RIMs）. Postzygotic RIMs are mainly products of genetic differences and thus their strength increases with elapsed divergence time. The relationship between postzygotic repro- ductive isolation and genetic divergence, however, differs considerably among major clades of vertebrates. We reviewed the available literature providing empirical evidence of natural and/or experimental hybridization between distinct species of lizards （squamates except snakes）. We found that hybridization events are widely distributed among nearly all major lizard clades. The majority of research focuses on parthenogenetic species and/or polyploid hybrids in families Lacertidae, Teiidae and Gekkonidae. Homoploid bisexual hybrids are mainly reported within Lacertidae and Iguania groups. As a proxy of genetic divergence of the hybridizing taxa we adopted nucleotide sequence distance （HKY85） of mitochondrial cyt b gene. The upper limit of genetic di- vergence was similar with regard to both parthenogenetic and bisexual hybrids. Maximum values of these distances between hy- bridizing species of lizards approached 18%-21%, which is comparable to or even exceeds the corresponding values reported for other principal clades of vertebrates. In spite of this, F1 hybrids are typically at least partially fertile in lizards and thus genetic introgression between highly divergent species is possible. The relationship between the genetic distance and hybrid fertility was not found [Current Zoology 61 （1）： 155-180, 2015].

关键词： Hybridization Introgression Fertility Viability Genetic divergence Lizards

Simple phenols in tropical woods determined by UHPLC-PDA and their antioxidant capacities: an experimental design for Randall extraction using environmentally friendly solvents

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Journal of Forestry Research 2020年第3期31卷 819-826页

作者： Marie Bartakova eva Dvorackova Lucie Chromcova Petr Hrdlicka Department of Chemistry and Biochemistry Mendel University in BrnoZemedelska 161300 BrnoCzech Republic

A comprehensive experimental design was developed to determine suitable conditions(volume, percentage of solvent, extraction temperature) for the ethanol extraction of phenolic compounds from ten tropical woody plants. Wenge, angelim vermelho, zebrano, merbau,tigerwood, angelim pedra, jatoba, angelim amargoso,massaranduba, and doussie woods were used in experiments. The effects of three independent variables and their interactions on the yields of cinnamic and benzoic acid derivates were analyzed using UHPLC-PDA. The most significant parameters were found to be solvent percentage,extraction volume, and extraction temperature. Optimal conditions for the extraction of phenolic compound contents were an 80℃ extraction temperature, a 30 mL extraction volume, and the use of pure water as the extraction solvent. The tested species of woods contained mainly cinnamic acid derivates. Water extracts after hydrolysis contained greater amounts of cinnamic acid derivates than those extracts from non-hydrolyzed *** total phenolics content was highest in water extracts of tigerwood, wenge and merbau;however, the extract of merbau wood was a stronger radical scavenger in ABTS?áassays: 34.11 ± 0.02 mM Trolox equivalents per g of dry extract. The main compounds possessing antioxidant activity in the extracts of vermelho wood assessed by UHPLC analysis were hydroxycinnamic acids.

关键词： Phenolic compounds Tropical woods Ultrahigh-performance liquid chromatography Antioxidant capacity