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Martínez-Peña R, Vergara-Díaz O, Schlereth A, Höhne M, Morcuende R, Nieto-Taladriz MT, Araus JL, Aparicio N, Vicente R. Analysis of durum wheat photosynthetic organs during grain filling reveals the ear as a water stress-tolerant organ and the peduncle as the largest pool of primary metabolites. Planta 2023; 257:81. [PMID: 36917306 PMCID: PMC10014764 DOI: 10.1007/s00425-023-04115-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 03/04/2023] [Indexed: 06/18/2023]
Abstract
The pool of carbon- and nitrogen-rich metabolites is quantitatively relevant in non-foliar photosynthetic organs during grain filling, which have a better response to water limitation than flag leaves. The response of durum wheat to contrasting water regimes has been extensively studied at leaf and agronomic level in previous studies, but the water stress effects on source-sink dynamics, particularly non-foliar photosynthetic organs, is more limited. Our study aims to investigate the response of different photosynthetic organs to water stress and to quantify the pool of carbon and nitrogen metabolites available for grain filling. Five durum wheat varieties were grown in field trials in the Spanish region of Castile and León under irrigated and rainfed conditions. Water stress led to a significant decrease in yield, biomass, and carbon and nitrogen assimilation, improved water use efficiency, and modified grain quality traits in the five varieties. The pool of carbon (glucose, glucose-6-phosphate, fructose, sucrose, starch, and malate) and nitrogen (glutamate, amino acids, proteins and chlorophylls) metabolites in leaf blades and sheaths, peduncles, awns, glumes and lemmas were also analysed. The results showed that the metabolism of the blades and peduncles was the most susceptible to water stress, while ear metabolism showed higher stability, particularly at mid-grain filling. Interestingly, the total metabolite content per organ highlighted that a large source of nutrients, which may be directly involved in grain filling, are found outside the blades, with the peduncles being quantitatively the most relevant. We conclude that yield improvements in our Mediterranean agro-ecosystem are highly linked to the success of shoots in producing ears and a higher number of grains, while grain filling is highly dependent on the capacity of non-foliar organs to fix CO2 and N. The ear organs show higher stress resilience than other organs, which deserves our attention in future breeding programmes.
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Affiliation(s)
- Raquel Martínez-Peña
- Cereals Group, Section of Herbaceous, Agro-Technological Institute of Castile and León, Junta de Castile and León, Valladolid, Spain
| | - Omar Vergara-Díaz
- Plant Ecophysiology and Metabolism Group, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Armin Schlereth
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Rosa Morcuende
- Institute of Natural Resources and Agrobiology of Salamanca (IRNASA), Consejo Superior de Investigaciones Científicas (CSIC), Salamanca, Spain
| | - María Teresa Nieto-Taladriz
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - José Luis Araus
- Integrative Crop Ecophysiology Group, Section of Plant Physiology, Faculty of Biology, University of Barcelona, Barcelona, and AGROTECNIO-CERCA Center, Lleida, Spain
| | - Nieves Aparicio
- Cereals Group, Section of Herbaceous, Agro-Technological Institute of Castile and León, Junta de Castile and León, Valladolid, Spain
| | - Rubén Vicente
- Plant Ecophysiology and Metabolism Group, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal.
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany.
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Alexandre Moraes T, Mengin V, Peixoto B, Encke B, Krohn N, Höhne M, Krause U, Stitt M. The circadian clock mutant lhy cca1 elf3 paces starch mobilization to dawn despite severely disrupted circadian clock function. Plant Physiol 2022; 189:2332-2356. [PMID: 35567528 PMCID: PMC9348821 DOI: 10.1093/plphys/kiac226] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 04/22/2022] [Indexed: 06/15/2023]
Abstract
Many plants, including Arabidopsis (Arabidopsis thaliana), accumulate starch in the daytime and remobilize it to support maintenance and growth at night. Starch accumulation is increased when carbon is in short supply, for example, in short photoperiods. Mobilization is paced to exhaust starch around dawn, as anticipated by the circadian clock. This diel pattern of turnover is largely robust against loss of day, dawn, dusk, or evening clock components. Here, we investigated diel starch turnover in the triple circadian clock mutant lhy cca1 elf3, which lacks the LATE ELONGATED HYPOCOTYL and the CIRCADIAN CLOCK-ASSOCIATED1 (CCA1) dawn components and the EARLY FLOWERING3 (ELF3) evening components of the circadian clock. The diel oscillations of transcripts for the remaining clock components and related genes like REVEILLE and PHYTOCHROME-INTERACING FACTOR family members exhibited attenuated amplitudes and altered peak time, weakened dawn dominance, and decreased robustness against changes in the external light-dark cycle. The triple mutant was unable to increase starch accumulation in short photoperiods. However, it was still able to pace starch mobilization to around dawn in different photoperiods and growth irradiances and to around 24 h after the previous dawn in T17 and T28 cycles. The triple mutant was able to slow down starch mobilization after a sudden low-light day or a sudden early dusk, although in the latter case it did not fully compensate for the lengthened night. Overall, there was a slight trend to less linear mobilization of starch. Thus, starch mobilization can be paced rather robustly to dawn despite a major disruption of the transcriptional clock. It is proposed that temporal information can be delivered from clock components or a semi-autonomous oscillator.
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Affiliation(s)
| | - Virginie Mengin
- School of Life Sciences, University of Essex, Colchester CO4 3SQ, UK
| | - Bruno Peixoto
- Instituto Gulbenkian de Ciência, Oeiras 2780-156,Portugal
- GREEN-IT Bioresources for Sustainability, ITQB NOVA, Oeiras 2780-157,Portugal
| | - Beatrice Encke
- Systematic Botany and Biodiversity, Humboldt University of Berlin, Berlin D-10115, Germany
| | - Nicole Krohn
- Abteilung für Parodontologie und Synoptische Zahnmedizin, Charité Universitätsmedizin, Berlin 14197, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany
| | - Ursula Krause
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany
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3
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Treves H, Küken A, Arrivault S, Ishihara H, Hoppe I, Erban A, Höhne M, Moraes TA, Kopka J, Szymanski J, Nikoloski Z, Stitt M. Carbon flux through photosynthesis and central carbon metabolism show distinct patterns between algae, C 3 and C 4 plants. Nat Plants 2022; 8:78-91. [PMID: 34949804 PMCID: PMC8786664 DOI: 10.1038/s41477-021-01042-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 11/09/2021] [Indexed: 05/26/2023]
Abstract
Photosynthesis-related pathways are regarded as a promising avenue for crop improvement. Whilst empirical studies have shown that photosynthetic efficiency is higher in microalgae than in C3 or C4 crops, the underlying reasons remain unclear. Using a tailor-made microfluidics labelling system to supply 13CO2 at steady state, we investigated in vivo labelling kinetics in intermediates of the Calvin Benson cycle and sugar, starch, organic acid and amino acid synthesis pathways, and in protein and lipids, in Chlamydomonas reinhardtii, Chlorella sorokiniana and Chlorella ohadii, which is the fastest growing green alga on record. We estimated flux patterns in these algae and compared them with published and new data from C3 and C4 plants. Our analyses identify distinct flux patterns supporting faster growth in photosynthetic cells, with some of the algae exhibiting faster ribulose 1,5-bisphosphate regeneration and increased fluxes through the lower glycolysis and anaplerotic pathways towards the tricarboxylic acid cycle, amino acid synthesis and lipid synthesis than in higher plants.
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Affiliation(s)
- Haim Treves
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany.
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel.
| | - Anika Küken
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
- Bioinformatics group, University of Potsdam, Potsdam, Germany
| | | | - Hirofumi Ishihara
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Ines Hoppe
- Bioinformatics group, University of Potsdam, Potsdam, Germany
| | - Alexander Erban
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Melanie Höhne
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Thiago Alexandre Moraes
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
- Crop Science Centre, University of Cambridge, Cambridge, UK
| | - Joachim Kopka
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Jedrzej Szymanski
- Department of Molecular Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, OT Gatersleben, Germany
| | - Zoran Nikoloski
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
- Bioinformatics group, University of Potsdam, Potsdam, Germany
| | - Mark Stitt
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
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Martínez-Peña R, Schlereth A, Höhne M, Encke B, Morcuende R, Nieto-Taladriz MT, Araus JL, Aparicio N, Vicente R. Source-Sink Dynamics in Field-Grown Durum Wheat Under Contrasting Nitrogen Supplies: Key Role of Non-Foliar Organs During Grain Filling. Front Plant Sci 2022; 13:869680. [PMID: 35574116 PMCID: PMC9100808 DOI: 10.3389/fpls.2022.869680] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 03/31/2022] [Indexed: 05/08/2023]
Abstract
The integration of high-throughput phenotyping and metabolic approaches is a suitable strategy to study the genotype-by-environment interaction and identify novel traits for crop improvement from canopy to an organ level. Our aims were to study the phenotypic and metabolic traits that are related to grain yield and quality at canopy and organ levels, with a special focus on source-sink coordination under contrasting N supplies. Four modern durum wheat varieties with contrasting grain yield were grown in field conditions under two N fertilization levels in north-eastern Spain. We evaluated canopy vegetation indices taken throughout the growing season, physiological and metabolic traits in different photosynthetic organs (flag leaf blade, sheath, peduncle, awn, glume, and lemma) at anthesis and mid-grain filling stages, and agronomic and grain quality traits at harvest. Low N supply triggered an imbalance of C and N coordination at the whole plant level, leading to a reduction of grain yield and nutrient composition. The activities of key enzymes in C and N metabolism as well as the levels of photoassimilates showed that each organ plays an important role during grain filling, some with a higher photosynthetic capacity, others for nutrient storage for later stages of grain filling, or N assimilation and recycling. Interestingly, the enzyme activities and sucrose content of the ear organs were positively associated with grain yield and quality, suggesting, together with the regression models using isotope signatures, the potential contribution of these organs during grain filling. This study highlights the use of holistic approaches to the identification of novel targets to improve grain yield and quality in C3 cereals and the key role of non-foliar organs at late-growth stages.
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Affiliation(s)
- Raquel Martínez-Peña
- Group of Cereals, Section of Herbaceous, Instituto Tecnológico Agrario de Castilla y León (ITACyL), Junta de Castilla y León, Valladolid, Spain
| | - Armin Schlereth
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Beatrice Encke
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Rosa Morcuende
- Institute of Natural Resources and Agrobiology of Salamanca (IRNASA), Consejo Superior de Investigaciones Científicas (CSIC), Salamanca, Spain
| | | | - José Luis Araus
- Integrative Crop Ecophysiology Group, Section of Plant Physiology, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Nieves Aparicio
- Group of Cereals, Section of Herbaceous, Instituto Tecnológico Agrario de Castilla y León (ITACyL), Junta de Castilla y León, Valladolid, Spain
| | - Rubén Vicente
- Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Plant Ecophysiology and Metabolism Group, Oeiras, Portugal
- *Correspondence: Rubén Vicente
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5
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Peixoto B, Moraes TA, Mengin V, Margalha L, Vicente R, Feil R, Höhne M, Sousa AGG, Lilue J, Stitt M, Lunn JE, Baena-González E. Impact of the SnRK1 protein kinase on sucrose homeostasis and the transcriptome during the diel cycle. Plant Physiol 2021; 187:1357-1373. [PMID: 34618060 PMCID: PMC8566312 DOI: 10.1093/plphys/kiab350] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 07/09/2021] [Indexed: 05/04/2023]
Abstract
SNF1-related Kinase 1 (SnRK1) is an evolutionarily conserved protein kinase with key functions in energy management during stress responses in plants. To address a potential role of SnRK1 under favorable conditions, we performed a metabolomic and transcriptomic characterization of rosettes of 20-d-old Arabidopsis (Arabidopsis thaliana) plants of SnRK1 gain- and loss-of-function mutants during the regular diel cycle. Our results show that SnRK1 manipulation alters the sucrose and trehalose 6-phosphate (Tre6P) relationship, influencing how the sucrose content is translated into Tre6P accumulation and modulating the flux of carbon to the tricarboxylic acid cycle downstream of Tre6P signaling. On the other hand, daily cycles of Tre6P accumulation were accompanied by changes in SnRK1 signaling, leading to a maximum in the expression of SnRK1-induced genes at the end of the night, when Tre6P levels are lowest, and to a minimum at the end of the day, when Tre6P levels peak. The expression of SnRK1-induced genes was strongly reduced by transient Tre6P accumulation in an inducible Tre6P synthase (otsA) line, further suggesting the involvement of Tre6P in the diel oscillations in SnRK1 signaling. Transcriptional profiling of wild-type plants and SnRK1 mutants also uncovered defects that are suggestive of an iron sufficiency response and of a matching induction of sulfur acquisition and assimilation when SnRK1 is depleted. In conclusion, under favorable growth conditions, SnRK1 plays a role in sucrose homeostasis and transcriptome remodeling in autotrophic tissues and its activity is influenced by diel fluctuations in Tre6P levels.
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Affiliation(s)
- Bruno Peixoto
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal and GREEN-IT Bioresources for Sustainability, ITQB NOVA, 2780-157 Oeiras, Portugal
| | - Thiago A Moraes
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
- Present address: Crop Science Centre, Lawrence Weaver Road, Cambridge CB3 0LE, UK
| | - Virginie Mengin
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
- Present address: University of Essex, School of Life Sciences, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Leonor Margalha
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal and GREEN-IT Bioresources for Sustainability, ITQB NOVA, 2780-157 Oeiras, Portugal
| | - Rubén Vicente
- GREEN-IT Bioresources for Sustainability, ITQB NOVA, 2780-157 Oeiras, Portugal
| | - Regina Feil
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - António G G Sousa
- Instituto Gulbenkian de Ciência, Bioinformatics Unit, 2780-156 Oeiras, Portugal
| | - Jingtao Lilue
- Instituto Gulbenkian de Ciência, Bioinformatics Unit, 2780-156 Oeiras, Portugal
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - John E Lunn
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Elena Baena-González
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal and GREEN-IT Bioresources for Sustainability, ITQB NOVA, 2780-157 Oeiras, Portugal
- Author for communication:
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Moraes TA, Mengin V, Annunziata MG, Encke B, Krohn N, Höhne M, Stitt M. Response of the Circadian Clock and Diel Starch Turnover to One Day of Low Light or Low CO 2. Plant Physiol 2019; 179:1457-1478. [PMID: 30670603 PMCID: PMC6446786 DOI: 10.1104/pp.18.01418] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 01/09/2019] [Indexed: 05/18/2023]
Abstract
Diel starch turnover responds rapidly to changes in the light regime. We investigated if these responses require changes in the temporal dynamics of the circadian clock. Arabidopsis (Arabidopsis thaliana) was grown in a 12-h photoperiod for 19 d, shifted to three different reduced light levels or to low CO2 for one light period, and returned to growth conditions. The treatments produced widespread changes in clock transcript abundance. However, almost all of the changes were restricted to extreme treatments that led to carbon starvation and were small compared to the magnitude of the circadian oscillation. Changes included repression of EARLY FLOWERNG 4, slower decay of dusk components, and a slight phase delay at the next dawn, possibly due to abrogated Evening Complex function and sustained expression of PHYTOCHROME INTERACTING FACTORs and REVEILLEs during the night. Mobilization of starch in the night occurred in a linear manner and was paced to dawn, both in moderate treatments that did not alter clock transcripts and in extreme treatments that led to severe carbon starvation. We conclude that pacing of starch mobilization to dawn does not require retrograde carbon signaling to the transcriptional clock. On the following day, growth decreased, sugars rose, and starch accumulation was stimulated in low-light-treated plants compared to controls. This adaptive response was marked after moderate treatments and occurred independently of changes in the transcriptional clock. It is probably a time-delayed response to low-C signaling in the preceding 24-h cycle, possibly including changes in PHYTOCHROME INTERACTING FACTOR and REVEILLE expression.
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Affiliation(s)
- Thiago Alexandre Moraes
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany
| | - Virginie Mengin
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany
| | - Maria Grazia Annunziata
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany
| | - Beatrice Encke
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany
| | - Nicole Krohn
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany
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Flis A, Mengin V, Ivakov AA, Mugford ST, Hubberten HM, Encke B, Krohn N, Höhne M, Feil R, Hoefgen R, Lunn JE, Millar AJ, Smith AM, Sulpice R, Stitt M. Multiple circadian clock outputs regulate diel turnover of carbon and nitrogen reserves. Plant Cell Environ 2019; 42:549-573. [PMID: 30184255 DOI: 10.1111/pce.13440] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 08/27/2018] [Accepted: 08/31/2018] [Indexed: 05/09/2023]
Abstract
Plants accumulate reserves in the daytime to support growth at night. Circadian regulation of diel reserve turnover was investigated by profiling starch, sugars, glucose 6-phosphate, organic acids, and amino acids during a light-dark cycle and after transfer to continuous light in Arabidopsis wild types and in mutants lacking dawn (lhy cca1), morning (prr7 prr9), dusk (toc1, gi), or evening (elf3) clock components. The metabolite time series were integrated with published time series for circadian clock transcripts to identify circadian outputs that regulate central metabolism. (a) Starch accumulation was slower in elf3 and prr7 prr9. It is proposed that ELF3 positively regulates starch accumulation. (b) Reducing sugars were high early in the T-cycle in elf3, revealing that ELF3 negatively regulates sucrose recycling. (c) The pattern of starch mobilization was modified in all five mutants. A model is proposed in which dawn and dusk/evening components interact to pace degradation to anticipated dawn. (d) An endogenous oscillation of glucose 6-phosphate revealed that the clock buffers metabolism against the large influx of carbon from photosynthesis. (e) Low levels of organic and amino acids in lhy cca1 and high levels in prr7 prr9 provide evidence that the dawn components positively regulate the accumulation of amino acid reserves.
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Affiliation(s)
- Anna Flis
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Virginie Mengin
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Alexander A Ivakov
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Sam T Mugford
- John Innes Centre, Norwich Research Park, Norwich, UK
| | | | - Beatrice Encke
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Nicole Krohn
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Regina Feil
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Rainer Hoefgen
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - John E Lunn
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Andrew J Millar
- SynthSys and School of Biological Sciences, C.H. Waddington Building, University of Edinburgh, Edinburgh, UK
| | | | - Ronan Sulpice
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
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Japhet MO, Famurewa O, Adesina OA, Opaleye OO, Wang B, Höhne M, Bock CT, Mas Marques A, Niendorf S. Viral gastroenteritis among children of 0-5 years in Nigeria: Characterization of the first Nigerian aichivirus, recombinant noroviruses and detection of a zoonotic astrovirus. J Clin Virol 2018; 111:4-11. [PMID: 30580015 DOI: 10.1016/j.jcv.2018.12.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 11/14/2018] [Accepted: 12/16/2018] [Indexed: 11/18/2022]
Abstract
BACKGROUND Viruses are the leading cause of acute gastroenteritis in children worldwide. Understanding of the occurrence and genetic diversity of these viruses can help to prevent infections. OBJECTIVES The present study describes the presence, genetic diversity and possible recombination of five enteric viruses in children with gastroenteritis in Southwestern Nigeria. STUDY DESIGN From August 2012 to December 2013, stool samples and sociodemographic data of 103 diarrheic children <5 years were collected to detect and characterize rotavirus A, norovirus, human astrovirus, aichivirus and sapovirus using PCR techniques followed by sequencing and phylogenetic analyses. RESULTS At least one virus was identified in 58.3% (60/103) of the stool samples. Rotavirus, norovirus and astrovirus were detected in 39.8% (41/103), 10.7% (11/103), and 6.8% (7/103) respectively. Notably, aichivirus was detected for the first time in Nigeria (1/103; 0.97%). Sapovirus was not detected in the study. Co-infections with rotavirus were observed in eight samples either with norovirus or astrovirus or aichivirus. Phylogenetic analyses of different genome regions of norovirus positive samples provided indication for recombinant norovirus strains. A novel astrovirus strain closely related to canine astrovirus was identified and further characterized for the first time. CONCLUSIONS Viruses are the common cause of acute gastroenteritis in Nigerian infants with rotavirus as most frequently detected pathogen. New norovirus recombinants and a not yet detected zoonotic astrovirus were circulating in Southwestern Nigeria, providing new information about emerging and unusual strains of viruses causing diarrhea.
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Affiliation(s)
- M O Japhet
- Department of Microbiology, Faculty of Science, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria; Department of Microbiology, Faculty of Science, Ekiti State University, Ado-Ekiti, Ekiti State, Nigeria; Department of Infectious Diseases, Unit of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch Institute, Berlin, Germany
| | - O Famurewa
- Department of Microbiology, Faculty of Science, Ekiti State University, Ado-Ekiti, Ekiti State, Nigeria; Department of Biological Sciences, Microbiology Unit, Kings University, Odeomu, Osun State, Nigeria
| | - O A Adesina
- Department of Microbiology, Faculty of Science, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
| | - O O Opaleye
- Department of Medical Microbiology and Parasitology, Ladoke Akintola University, Osogbo, Osun state, Nigeria
| | - B Wang
- Department of Infectious Diseases, Unit of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch Institute, Berlin, Germany
| | - M Höhne
- Department of Infectious Diseases, Unit of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch Institute, Berlin, Germany
| | - C T Bock
- Department of Infectious Diseases, Unit of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch Institute, Berlin, Germany; Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Andreas Mas Marques
- Department of Infectious Diseases, Unit of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch Institute, Berlin, Germany
| | - S Niendorf
- Department of Infectious Diseases, Unit of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch Institute, Berlin, Germany.
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Küken A, Sommer F, Yaneva-Roder L, Mackinder LCM, Höhne M, Geimer S, Jonikas MC, Schroda M, Stitt M, Nikoloski Z, Mettler-Altmann T. Effects of microcompartmentation on flux distribution and metabolic pools in Chlamydomonas reinhardtii chloroplasts. eLife 2018; 7:e37960. [PMID: 30306890 PMCID: PMC6235561 DOI: 10.7554/elife.37960] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 09/27/2018] [Indexed: 11/16/2022] Open
Abstract
Cells and organelles are not homogeneous but include microcompartments that alter the spatiotemporal characteristics of cellular processes. The effects of microcompartmentation on metabolic pathways are however difficult to study experimentally. The pyrenoid is a microcompartment that is essential for a carbon concentrating mechanism (CCM) that improves the photosynthetic performance of eukaryotic algae. Using Chlamydomonas reinhardtii, we obtained experimental data on photosynthesis, metabolites, and proteins in CCM-induced and CCM-suppressed cells. We then employed a computational strategy to estimate how fluxes through the Calvin-Benson cycle are compartmented between the pyrenoid and the stroma. Our model predicts that ribulose-1,5-bisphosphate (RuBP), the substrate of Rubisco, and 3-phosphoglycerate (3PGA), its product, diffuse in and out of the pyrenoid, respectively, with higher fluxes in CCM-induced cells. It also indicates that there is no major diffusional barrier to metabolic flux between the pyrenoid and stroma. Our computational approach represents a stepping stone to understanding microcompartmentalized CCM in other organisms.
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Affiliation(s)
- Anika Küken
- Max Planck Institute of Molecular Plant PhysiologyPotsdam-GolmGermany
- Bioinformatics Group, Institute of Biochemistry and BiologyUniversity of PotsdamPotsdamGermany
| | - Frederik Sommer
- Max Planck Institute of Molecular Plant PhysiologyPotsdam-GolmGermany
| | | | - Luke CM Mackinder
- Department of Plant BiologyCarnegie Institution for ScienceStanfordUnited States
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant PhysiologyPotsdam-GolmGermany
| | - Stefan Geimer
- Institute of Cell BiologyUniversity of BayreuthBayreuthGermany
| | - Martin C Jonikas
- Department of Plant BiologyCarnegie Institution for ScienceStanfordUnited States
| | - Michael Schroda
- Max Planck Institute of Molecular Plant PhysiologyPotsdam-GolmGermany
| | - Mark Stitt
- Max Planck Institute of Molecular Plant PhysiologyPotsdam-GolmGermany
| | - Zoran Nikoloski
- Max Planck Institute of Molecular Plant PhysiologyPotsdam-GolmGermany
- Bioinformatics Group, Institute of Biochemistry and BiologyUniversity of PotsdamPotsdamGermany
| | - Tabea Mettler-Altmann
- Max Planck Institute of Molecular Plant PhysiologyPotsdam-GolmGermany
- Cluster of Excellence on Plant SciencesHeinrich-Heine UniversityDüsseldorfGermany
- Institute of Plant BiochemistryHeinrich-Heine UniversityDüsseldorfGermany
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10
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Niendorf S, Jacobsen S, Faber M, Eis-Hübinger AM, Hofmann J, Zimmermann O, Höhne M, Bock CT. Steep rise in norovirus cases and emergence of a new recombinant strain GII.P16-GII.2, Germany, winter 2016. ACTA ACUST UNITED AC 2017; 22:30447. [PMID: 28181902 PMCID: PMC5388089 DOI: 10.2807/1560-7917.es.2017.22.4.30447] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 01/25/2017] [Indexed: 12/17/2022]
Abstract
Since early November 2016, the number of laboratory-confirmed norovirus infections reported in Germany has been increasing steeply. Here, we report the detection and genetic characterisation of an emerging norovirus recombinant, GII.P16-GII.2. This strain was frequently identified as the cause of sporadic cases as well as outbreaks in nine federal states of Germany. Our findings suggest that the emergence of GII.P16-GII.2 contributed to rising case numbers of norovirus gastroenteritis in Germany.
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Affiliation(s)
- S Niendorf
- Department of Infectious Diseases, Robert Koch-Institute, Berlin, Germany.,Consultant Laboratory for Noroviruses, Robert Koch-Institute, Berlin, Germany
| | - S Jacobsen
- Department of Infectious Diseases, Robert Koch-Institute, Berlin, Germany.,Consultant Laboratory for Noroviruses, Robert Koch-Institute, Berlin, Germany
| | - M Faber
- Department for Infectious Disease Epidemiology, Robert Koch-Institute, Berlin, Germany
| | - A M Eis-Hübinger
- Institute of Virology, University of Bonn Medical Centre, Bonn, Germany
| | - J Hofmann
- Institute of Medical Virology, Charité University Medicine, Berlin, and Labor Berlin, Charité-Vivantes GmbH, Berlin, Germany
| | - O Zimmermann
- Institute of Medical Microbiology, Göttingen, Germany
| | - M Höhne
- Department of Infectious Diseases, Robert Koch-Institute, Berlin, Germany.,Consultant Laboratory for Noroviruses, Robert Koch-Institute, Berlin, Germany
| | - C T Bock
- Department of Infectious Diseases, Robert Koch-Institute, Berlin, Germany
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11
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Peulecke N, Müller BH, Spannenberg A, Höhne M, Rosenthal U, Wöhl A, Müller W, Alqahtani A, Al Hazmi M. Ligands with an NPNPN-framework and their application in chromium catalysed ethene tri-/tetramerization. Dalton Trans 2016; 45:8869-74. [PMID: 27151679 DOI: 10.1039/c6dt01109h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Novel Cr(iii) catalysts supported by linear phosph(iii)azanes of the type R(1)R(2)N-P(Ph)-NR(3)-P(Ph)-NR(4)R(5) have been prepared, all of which, upon activation with MMAO-3A, are highly active for ethene tri-/tetramerization with considerable selectivity. The effect of ligand substitution as well as solvent on the catalytic performance has been examined.
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Affiliation(s)
- N Peulecke
- Leibniz-Institut für Katalyse an der Universität Rostock e.V., Albert-Einstein-Str. 29 A, 18059 Rostock, Germany.
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12
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Figueroa CM, Feil R, Ishihara H, Watanabe M, Kölling K, Krause U, Höhne M, Encke B, Plaxton WC, Zeeman SC, Li Z, Schulze WX, Hoefgen R, Stitt M, Lunn JE. Trehalose 6-phosphate coordinates organic and amino acid metabolism with carbon availability. Plant J 2016; 85:410-23. [PMID: 26714615 DOI: 10.1111/tpj.13114] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 12/14/2015] [Accepted: 12/21/2015] [Indexed: 05/18/2023]
Abstract
Trehalose 6-phosphate (Tre6P) is an essential signal metabolite in plants, linking growth and development to carbon metabolism. The sucrose-Tre6P nexus model postulates that Tre6P acts as both a signal and negative feedback regulator of sucrose levels. To test this model, short-term metabolic responses to induced increases in Tre6P levels were investigated in Arabidopsis thaliana plants expressing the Escherichia coli Tre6P synthase gene (otsA) under the control of an ethanol-inducible promoter. Increased Tre6P levels led to a transient decrease in sucrose content, post-translational activation of nitrate reductase and phosphoenolpyruvate carboxylase, and increased levels of organic and amino acids. Radio-isotope ((14)CO2) and stable isotope ((13)CO2) labelling experiments showed no change in the rates of photoassimilate export in plants with elevated Tre6P, but increased labelling of organic acids. We conclude that high Tre6P levels decrease sucrose levels by stimulating nitrate assimilation and anaplerotic synthesis of organic acids, thereby diverting photoassimilates away from sucrose to generate carbon skeletons and fixed nitrogen for amino acid synthesis. These results are consistent with the sucrose-Tre6P nexus model, and implicate Tre6P in coordinating carbon and nitrogen metabolism in plants.
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Affiliation(s)
- Carlos M Figueroa
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - Regina Feil
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - Hirofumi Ishihara
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - Mutsumi Watanabe
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - Katharina Kölling
- Department of Biology, Institute of Agricultural Sciences, ETH Zurich, Zurich, 8092, Switzerland
| | - Ursula Krause
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - Beatrice Encke
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - William C Plaxton
- Department of Biology and Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Samuel C Zeeman
- Department of Biology, Institute of Agricultural Sciences, ETH Zurich, Zurich, 8092, Switzerland
| | - Zhi Li
- Department of Plant Systems Biology, University of Hohenheim, Stuttgart, 70593, Germany
| | - Waltraud X Schulze
- Department of Plant Systems Biology, University of Hohenheim, Stuttgart, 70593, Germany
| | - Rainer Hoefgen
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
| | - John E Lunn
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
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13
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Altmann MM, Wrede CE, Peetz D, Höhne M, Stroszczynski C, Herold T. Age-Dependent D-dimer Cut-off to Avoid Unnecessary CT-Exams for Ruling-out Pulmonary Embolism. ROFO-FORTSCHR RONTG 2015; 187:795-800. [PMID: 26308535 DOI: 10.1055/s-0035-1553428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE To evaluate the effect of an age-dependent D-Dimer cut-off in patients who underwent a computed tomography pulmonary angiogram (CTPA) for suspected pulmonary embolism (PE) Material and Methods: Retrospective application of an age-dependent D-dimer cut-off (age/100 in patients aged over 50) in 530 consecutive patients, both in- and outpatients, aged over 18, who underwent CTPA for suspected PE according to the guidelines. RESULTS The application of an age-dependent D-dimer cut-off showed a now negative test-result in 17 of 530 patients (3.2%). The proportion was 4.1% (17 of 418) in patients aged over 50. None of these 17 cases was diagnosed with PE in CTPA, the false-negative rate was 0%. The effect could be seen in outpatients (14 of 377 [3.7%]) as well as in inpatients(3 of 153 [2.0%]) with no statistically significant difference (p > 0.05). CONCLUSION The application of an age-dependent D-dimer cut-off as part of the guidline-based algorithm for suspected PE reduced the number of necessary CTPA in outpatients as well as in inpatients. KEY POINTS The application of an age-dependent D-dimer cut-off reduces the number of CTPA as part of the diagnostic algorithm in patients suspected for PENo reduction in diagnostic safety was found. The age adjustement performed equally in outpatients and inpatients
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Affiliation(s)
- M M Altmann
- Radiology, HELIOS Klinikum Berlin-Buch, Berlin, Germany
| | - C E Wrede
- Emergency Department, HELIOS Klinikum Berlin-Buch, Berlin, Germany
| | - D Peetz
- Laboratory Medicine, HELIOS Klinikum Berlin-Buch, Berlin, Germany
| | - M Höhne
- Radiology, HELIOS Klinikum Berlin-Buch, Berlin, Germany
| | | | - T Herold
- Radiology, HELIOS Klinikum Berlin-Buch, Berlin, Germany
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14
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Franke M, Vechtel J, Dafinger C, Höhne M, Göbel H, Körber F, Maintz D, Schermer B, Persigehl T. Evaluierung und Therapiemonitoring der polyzystischen Nierendegeneration mittels quantitativem T2-mapping und DWI im juvenile cystic kidney (jck)- Mausmodell. ROFO-FORTSCHR RONTG 2015. [DOI: 10.1055/s-0035-1550846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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15
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Pilkington SM, Encke B, Krohn N, Höhne M, Stitt M, Pyl ET. Relationship between starch degradation and carbon demand for maintenance and growth in Arabidopsis thaliana in different irradiance and temperature regimes. Plant Cell Environ 2015; 38:157-71. [PMID: 24905937 DOI: 10.1111/pce.12381] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 05/28/2014] [Accepted: 05/29/2014] [Indexed: 05/12/2023]
Abstract
Experiments were designed to compare the relationship between starch degradation and the use of carbon for maintenance and growth in Arabidopsis in source-limited and sink-limited conditions. It is known that starch degradation is regulated by the clock in source-limited plants, which degrade their starch in a linear manner such that it is almost but not completely exhausted at dawn. We asked whether this response is maintained under an extreme carbon deficit. Arabidopsis was subjected to a sudden combination of a day of low irradiance, to decrease starch at dusk, and a warm night. Starch was degraded in a linear manner through the night, even though the plants became acutely carbon starved. We conclude that starch degradation is not increased to meet demand in carbon-limited plants. This network property will allow stringent control of starch turnover in a fluctuating environment. In contrast, in sink-limited plants, which do not completely mobilize their starch during the night, starch degradation was accelerated in warm nights to meet the increased demand for maintenance and growth. Across all conditions, the rate of growth at night depends on the rate of starch degradation, whereas the rate of maintenance respiration decreases only when starch degradation is very slow.
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Affiliation(s)
- Sarah M Pilkington
- Max Planck Institute for Molecular Plant Physiology, Potsdam-Golm, 14476, Germany
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16
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Bentaib A, Bleyer A, Meynet N, Chaumeix N, Schramm B, Höhne M, Kostka P, Movahed M, Worapittayaporn S, Brähler T, Seok-Kang H, Povilaitis M, Kljenak I, Sathiah P. SARNET hydrogen deflagration benchmarks: Main outcomes and conclusions. ANN NUCL ENERGY 2014. [DOI: 10.1016/j.anucene.2014.07.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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17
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Nardozza S, Boldingh HL, Osorio S, Höhne M, Wohlers M, Gleave AP, MacRae EA, Richardson AC, Atkinson RG, Sulpice R, Fernie AR, Clearwater MJ. Metabolic analysis of kiwifruit (Actinidia deliciosa) berries from extreme genotypes reveals hallmarks for fruit starch metabolism. J Exp Bot 2013; 64:5049-63. [PMID: 24058160 PMCID: PMC3830485 DOI: 10.1093/jxb/ert293] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Tomato, melon, grape, peach, and strawberry primarily accumulate soluble sugars during fruit development. In contrast, kiwifruit (Actinidia Lindl. spp.) and banana store a large amount of starch that is released as soluble sugars only after the fruit has reached maturity. By integrating metabolites measured by gas chromatography-mass spectrometry, enzyme activities measured by a robot-based platform, and transcript data sets during fruit development of Actinidia deliciosa genotypes contrasting in starch concentration and size, this study identified the metabolic changes occurring during kiwifruit development, including the metabolic hallmarks of starch accumulation and turnover. At cell division, a rise in glucose (Glc) concentration was associated with neutral invertase (NI) activity, and the decline of both Glc and NI activity defined the transition to the cell expansion and starch accumulation phase. The high transcript levels of β-amylase 9 (BAM9) during cell division, prior to net starch accumulation, and the correlation between sucrose phosphate synthase (SPS) activity and sucrose suggest the occurrence of sucrose cycling and starch turnover. ADP-Glc pyrophosphorylase (AGPase) is identified as a key enzyme for starch accumulation in kiwifruit berries, as high-starch genotypes had 2- to 5-fold higher AGPase activity, which was maintained over a longer period of time and was also associated with enhanced and extended transcription of the AGPase large subunit 4 (APL4). The data also revealed that SPS and galactinol might affect kiwifruit starch accumulation, and suggest that phloem unloading into kiwifruit is symplastic. These results are relevant to the genetic improvement of quality traits such as sweetness and sugar/acid balance in a range of fruit species.
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Affiliation(s)
- Simona Nardozza
- The New Zealand Institute for Plant & Food Research Limited (PFR), Mt Albert Research Centre, Private Bag 92169, Auckland, New Zealand
| | - Helen L. Boldingh
- PFR, Ruakura Research Centre, Private Bag 3230, Hamilton, New Zealand
| | - Sonia Osorio
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Mark Wohlers
- The New Zealand Institute for Plant & Food Research Limited (PFR), Mt Albert Research Centre, Private Bag 92169, Auckland, New Zealand
| | - Andrew P. Gleave
- The New Zealand Institute for Plant & Food Research Limited (PFR), Mt Albert Research Centre, Private Bag 92169, Auckland, New Zealand
| | - Elspeth A. MacRae
- The New Zealand Institute for Plant & Food Research Limited (PFR), Mt Albert Research Centre, Private Bag 92169, Auckland, New Zealand
| | | | - Ross G. Atkinson
- The New Zealand Institute for Plant & Food Research Limited (PFR), Mt Albert Research Centre, Private Bag 92169, Auckland, New Zealand
| | - Ronan Sulpice
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Alisdair R. Fernie
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
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18
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Zhang N, Gibon Y, Gur A, Chen C, Lepak N, Höhne M, Zhang Z, Kroon D, Tschoep H, Stitt M, Buckler E. Fine quantitative trait loci mapping of carbon and nitrogen metabolism enzyme activities and seedling biomass in the maize IBM mapping population. Plant Physiol 2010; 154:1753-65. [PMID: 20971858 PMCID: PMC2996021 DOI: 10.1104/pp.110.165787] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Accepted: 10/20/2010] [Indexed: 05/04/2023]
Abstract
Understanding the genetic basis of nitrogen and carbon metabolism will accelerate the development of plant varieties with high yield and improved nitrogen use efficiency. A robotized platform was used to measure the activities of 10 enzymes from carbon and nitrogen metabolism in the maize (Zea mays) intermated B73 × Mo17 mapping population, which provides almost a 4-fold increase in genetic map distance compared with conventional mapping populations. Seedling/juvenile biomass was included to identify its genetic factors and relationships with enzyme activities. All 10 enzymes showed heritable variation in activity. There were strong positive correlations between activities of different enzymes, indicating that they are coregulated. Negative correlations were detected between biomass and the activity of six enzymes. In total, 73 significant quantitative trait loci (QTL) were found that influence the activity of these 10 enzymes and eight QTL that influence biomass. While some QTL were shared by different enzymes or biomass, we critically evaluated the probability that this may be fortuitous. All enzyme activity QTL were in trans to the known genomic locations of structural genes, except for single cis-QTL for nitrate reductase, Glu dehydrogenase, and shikimate dehydrogenase; the low frequency and low additive magnitude compared with trans-QTL indicate that cis-regulation is relatively unimportant versus trans-regulation. Two-gene epistatic interactions were identified for eight enzymes and for biomass, with three epistatic QTL being shared by two other traits; however, epistasis explained on average only 2.8% of the genetic variance. Overall, this study identifies more QTL at a higher resolution than previous studies of genetic variation in metabolism.
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Affiliation(s)
- Nengyi Zhang
- Institute for Genomic Diversity, Cornell University, Ithaca, New York 14853, USA.
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Na Ranong C, Hapke J, Höhne M, Roetzel W, Fieg G. Modellgestützte Simulation von Metallhydridreaktoren als Wärme- und Wasserstoffspeicher. CHEM-ING-TECH 2010. [DOI: 10.1002/cite.201050086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Piques M, Schulze WX, Höhne M, Usadel B, Gibon Y, Rohwer J, Stitt M. Ribosome and transcript copy numbers, polysome occupancy and enzyme dynamics in Arabidopsis. Mol Syst Biol 2009; 5:314. [PMID: 19888209 PMCID: PMC2779082 DOI: 10.1038/msb.2009.68] [Citation(s) in RCA: 240] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Accepted: 07/21/2009] [Indexed: 01/10/2023] Open
Abstract
Plants are exposed to continual changes in the environment. The daily alternation between light and darkness results in massive recurring changes in the carbon budget, and leads to widespread changes in transcript levels. These diurnal changes are superimposed on slower changes in the environment. Quantitative molecular information about the numbers of ribosomes, of transcripts for 35 enzymes in central metabolism and their loading into polysomes is used to estimate translation rates in Arabidopsis rosettes, and explore the consequences for important sub-processes in plant growth. Translation rates for individual enzyme are compared with their abundance in the rosette to predict which enzymes are subject to rapid turnover every day, and which are synthesized at rates that would allow only slow adjustments to sustained changes of the environment, or resemble those needed to support the observed rate of growth. Global translation rates are used to estimate the energy costs of protein synthesis and relate them to the plant carbon budget, in particular the rates of starch degradation and respiration at night.
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Affiliation(s)
- Maria Piques
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, Potsdam-Golm, Germany
| | - Waltraud X Schulze
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, Potsdam-Golm, Germany
| | - Melanie Höhne
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, Potsdam-Golm, Germany
| | - Björn Usadel
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, Potsdam-Golm, Germany
| | - Yves Gibon
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, Potsdam-Golm, Germany
| | - Johann Rohwer
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, Potsdam-Golm, Germany
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, Potsdam-Golm, Germany
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21
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Na Ranong C, Höhne M, Franzen J, Hapke J, Fieg G, Dornheim M, Eigen N, Bellosta von Colbe JM, Metz O. Concept, Design and Manufacture of a Prototype Hydrogen Storage Tank Based on Sodium Alanate. Chem Eng Technol 2009. [DOI: 10.1002/ceat.200900095] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Gibon Y, Pyl ET, Sulpice R, Lunn JE, Höhne M, Günther M, Stitt M. Adjustment of growth, starch turnover, protein content and central metabolism to a decrease of the carbon supply when Arabidopsis is grown in very short photoperiods. Plant Cell Environ 2009; 32:859-74. [PMID: 19236606 DOI: 10.1111/j.1365-3040.2009.01965.x] [Citation(s) in RCA: 204] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Arabidopsis was grown in a 12, 8, 4 or 3 h photoperiod to investigate how metabolism and growth adjust to a decreased carbon supply. There was a progressive increase in the rate of starch synthesis, decrease in the rate of starch degradation, decrease of malate and fumarate, decrease of the protein content and decrease of the relative growth rate. Carbohydrate and amino acids levels at the end of the night did not change. Activities of enzymes involved in photosynthesis, starch and sucrose synthesis and inorganic nitrogen assimilation remained high, whereas five of eight enzymes from glycolysis and organic acid metabolism showed a significant decrease of activity on a protein basis. Glutamate dehydrogenase activity increased. In a 2 h photoperiod, the total protein content and most enzyme activities decreased strongly, starch synthesis was inhibited, and sugars and amino acids levels rose at the end of the night and growth was completely inhibited. The rate of starch degradation correlated with the protein content and the relative growth rate across all the photoperiod treatments. It is discussed how a close coordination of starch turnover, the protein content and growth allows Arabidopsis to avoid carbon starvation, even in very short photoperiods.
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Affiliation(s)
- Yves Gibon
- Max Planck Institute of Molecular Plant Physiology, Golm , Germany
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23
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Höhne M. Eigenblutspende mit Tiefkühlkonservierung. Transfus Med Hemother 2009. [DOI: 10.1159/000222540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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24
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Na Ranong C, Höhne M, Franzen J, Hapke J, Fieg G, Dornheim M. Modellgestützte verfahrenstechnische Berechnung eines Metallhydridspeichers auf Natriumalanatbasis im Technikumsmaßstab. CHEM-ING-TECH 2009. [DOI: 10.1002/cite.200900008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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25
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Usadel B, Bläsing OE, Gibon Y, Poree F, Höhne M, Günter M, Trethewey R, Kamlage B, Poorter H, Stitt M. Multilevel genomic analysis of the response of transcripts, enzyme activities and metabolites in Arabidopsis rosettes to a progressive decrease of temperature in the non-freezing range. Plant Cell Environ 2008; 31:518-47. [PMID: 18088337 DOI: 10.1111/j.1365-3040.2007.01763.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
This paper characterizes the transcriptional and metabolic response of a chilling-tolerant species to an increasingly large decrease of the temperature. Arabidopsis Col-0 was grown at 20 degrees C and transferred to 17, 14, 12, 10 or 8 degrees C for 6 and 78 h, before harvesting the rosette and profiling >22 000 transcripts, >20 enzyme activities and >80 metabolites. Most parameters showed a qualitatively similar response across the entire temperature range, with the amplitude increasing as the temperature decreased. Transcripts typically showed large changes after 6 h, which were often damped by 78 h. Genes were induced for sucrose, proline, raffinose, tocopherol and polyamine synthesis, phenylpropanoid and flavonoid metabolism, fermentation, non-phosphorylating mitochondrial electron transport, RNA processing, and protein synthesis, targeting and folding. Genes were repressed for carbonic anhydrases, vacuolar invertase, and ethylene and jasmonic acid signalling. While some enzyme activities and metabolites changed rapidly, most changed slowly. After 6 h, there was an accumulation of phosphorylated intermediates, a shift of partitioning towards sucrose, and a perturbation of glycine decarboxylation and nitrogen metabolism. By 78 h, there was an increase of the overall protein content and many enzyme activities, a general increase of carbohydrates, organic and amino acids, and an increase of many stress-responsive metabolites including raffinose, proline, tocopherol and polyamines. When the responses of transcripts and metabolism were compared, there was little agreement after 6 h, but considerable agreement after 78 h. Comparison with the published studies indicated that much, but not all, of the response was orchestrated by the CBF programme. Overall, our results showed that transcription and metabolism responded in a continuous manner across a wide range of temperatures. The general increase of enzyme activities and metabolites emphasized the positive and compensatory nature of this response.
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Affiliation(s)
- Björn Usadel
- Max-Planck-Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476, Golm, Germany
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Usadel B, Bläsing OE, Gibon Y, Retzlaff K, Höhne M, Günther M, Stitt M. Global transcript levels respond to small changes of the carbon status during progressive exhaustion of carbohydrates in Arabidopsis rosettes. Plant Physiol 2008; 146:1834-61. [PMID: 18305208 PMCID: PMC2287354 DOI: 10.1104/pp.107.115592] [Citation(s) in RCA: 252] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2008] [Accepted: 01/31/2008] [Indexed: 05/18/2023]
Abstract
The balance between the supply and utilization of carbon (C) changes continually. It has been proposed that plants respond in an acclimatory manner, modifying C utilization to minimize harmful periods of C depletion. This hypothesis predicts that signaling events are initiated by small changes in C status. We analyzed the global transcriptional response to a gradual depletion of C during the night and an extension of the night, where C becomes severely limiting from 4 h onward. The response was interpreted using published datasets for sugar, light, and circadian responses. Hundreds of C-responsive genes respond during the night and others very early in the extended night. Pathway analysis reveals that biosynthesis and cellular growth genes are repressed during the night and genes involved in catabolism are induced during the first hours of the extended night. The C response is amplified by an antagonistic interaction with the clock. Light signaling is attenuated during the 24-h light/dark cycle. A model was developed that uses the response of 22K genes during a circadian cycle and their responses to C and light to predict global transcriptional responses during diurnal cycles of wild-type and starchless pgm mutant plants and an extended night in wild-type plants. By identifying sets of genes that respond at different speeds and times during C depletion, our extended dataset and model aid the analysis of candidates for C signaling. This is illustrated for AKIN10 and four bZIP transcription factors, and sets of genes involved in trehalose signaling, protein turnover, and starch breakdown.
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Affiliation(s)
- Björn Usadel
- Metanomics GmbH, Tegler Weg 33, 10589 Berlin, Germany.
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Pleyer U, Ruokonen P, Schmidt N, Feist E, Höhne M, Stanojlovic S. Ein Beitrag zur Anwendung von Mycophenolsäure bei Autoimmunerkrankungen des Auges: Können wir die Therapie optimieren? Klin Monbl Augenheilkd 2008; 225:66-9. [DOI: 10.1055/s-2008-1027134] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Sulpice R, Tschoep H, VON Korff M, Büssis D, Usadel B, Höhne M, Witucka-Wall H, Altmann T, Stitt M, Gibon Y. Description and applications of a rapid and sensitive non-radioactive microplate-based assay for maximum and initial activity of D-ribulose-1,5-bisphosphate carboxylase/oxygenase. Plant Cell Environ 2007; 30:1163-75. [PMID: 17661753 DOI: 10.1111/j.1365-3040.2007.01679.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
D-ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyses the first step in photosynthetic carbon assimilation and represents the largest sink for nitrogen in plants. Improvement of its kinetic properties or the efficiency with which it is used in planta would benefit photosynthesis, nitrogen and water use efficiency, and yield. This paper presents a new non-radioactive microplate-based assay, which determines the product [3-phosphoglycerate (3-PGA)] in an enzymic cycle between glycerol-3-phosphate dehydrogenase and glycerol-3-phosphate oxidase. High sensitivity permits use of highly diluted extracts, and a short reaction time to avoid problems due to fall-off. Throughput was several hundreds of samples per person per day. Sensitivity and convenience compared favourably with radioisotopic assays, which were previously used to assay Rubisco. Its use is illustrated in three applications. (1) Maximal and initial activities and the K(m) for ribulose-1,5-bisphosphate were determined in raw extracts of leaves from several species. Similar values were obtained from those in the literature. (2) Diurnal changes were compared in rosettes of wild-type (WT) Arabidopsis and the starchless pgm mutant. Despite these dramatic differences in carbon metabolism, Rubisco activity and activation were similar in both genotypes. (3) A preliminary association mapping study was performed with 118 Arabidopsis accessions, using 183 markers that probably cover approximately 3-8% of the total genome. At a P-value < 0.005, two, two and no quantitative trait loci (QTL) were found for Rubisco maximal activity, initial activity and activation state, respectively. Inspection of the genomic regions that span these markers revealed these QTL involved genes not previously implicated in the regulation of Rubisco expression or activity.
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Affiliation(s)
- Ronan Sulpice
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, D-14476 Golm, Germany
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Osuna D, Usadel B, Morcuende R, Gibon Y, Bläsing OE, Höhne M, Günter M, Kamlage B, Trethewey R, Scheible WR, Stitt M. Temporal responses of transcripts, enzyme activities and metabolites after adding sucrose to carbon-deprived Arabidopsis seedlings. Plant J 2007; 49:463-91. [PMID: 17217462 DOI: 10.1111/j.1365-313x.2006.02979.x] [Citation(s) in RCA: 193] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Arabidopsis seedlings were subjected to 2 days of carbon starvation, and then resupplied with 15 mm sucrose. The transcriptional and metabolic response was analyzed using ATH1 arrays, real-time quantitative (q)RT-PCR analysis of >2000 transcription regulators, robotized assays of enzymes from central metabolism and metabolite profiling. Sucrose led within 30 min to greater than threefold changes of the transcript levels for >100 genes, including 20 transcription regulators, 15 ubiquitin-targeting proteins, four trehalose phosphate synthases, autophagy protein 8e, several glutaredoxins and many genes of unknown function. Most of these genes respond to changes of endogenous sugars in Arabidopsis rosettes, making them excellent candidates for upstream components of sugar signaling pathways. Some respond during diurnal cycles, consistent with them acting in signaling pathways that balance the supply and utilization of carbon in normal growth conditions. By 3 h, transcript levels change for >1700 genes. This includes a coordinated induction of genes involved in carbohydrate synthesis, glycolysis, respiration, amino acid and nucleotide synthesis, DNA, RNA and protein synthesis and protein folding, and repression of genes involved in amino acid and lipid catabolism, photosynthesis and chloroplast protein synthesis and folding. The changes of transcripts are followed by a delayed activation of central metabolic pathways and growth processes, which use intermediates from these pathways. Sucrose and reducing sugars accumulate during the first 3-8 h, and starch for 24 h, showing that there is a delay until carbon utilization for growth recommences. Gradual changes of enzyme activities and metabolites are found for many metabolic pathways, including glycolysis, nitrate assimilation, the shikimate pathway and myoinositol, proline and fatty acid metabolism. After 3-8 h, there is a decrease of amino acids, followed by a gradual increase of protein.
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Affiliation(s)
- Daniel Osuna
- Max-Planck-Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Golm, Germany
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Schenkel K, Bremer V, Grabe C, Van Treeck U, Schreier E, Höhne M, Ammon A, Alpers K. Outbreak of hepatitis A in two federal states of Germany: bakery products as vehicle of infection. Epidemiol Infect 2006; 134:1292-8. [PMID: 16650329 PMCID: PMC2870508 DOI: 10.1017/s0950268806006212] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/2006] [Indexed: 11/07/2022] Open
Abstract
In April 2004, increased numbers of hepatitis A were noted in six neighbouring districts in Germany. Exploratory interviews showed that patients had consumed bakery products from company X where two employees had been diagnosed with hepatitis A in February. A case-control study of consumption of products of company X was carried out through telephone interviews. Altogether, 64 cases were identified. Fifty-two cases and 112 controls aged >or=16 years were included in the case-control study. In total, 46/52 cases and 37/112 controls had consumed company X products [odds ratio (OR) 15.5, 95% confidence interval (CI) 6.1-39.7]. Of these, 36/46 cases and 16/37 controls had consumed pastries (OR 4.7, 95% CI 1.8-12.3), 25/46 cases and 12/37 controls had consumed filled doughnuts (OR 2.5, 95% CI 1.0-6.1). Sequence analysis of the VP1-2A junction region indicated 100% strain homology between cases and an infected employee of company X. We recommended reinforcement of hygiene precautions, and consideration of a prolongation of compulsory work absence after post-exposure vaccination.
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Affiliation(s)
- K Schenkel
- Department for Infectious Diseases Epidemiology, Robert Koch-Institut, Berlin, Germany.
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Pfeiffer G, Oppitz N, Schöne S, Richter-Heine I, Höhne M, Koltermann C. [Analgesia of the axilla using a paravertebral catheter in the lamina technique]. Anaesthesist 2006; 55:423-7. [PMID: 16404582 DOI: 10.1007/s00101-005-0969-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A 62-year-old female suffered from therapy-resistant pain in the axilla after lymphadenectomy. The pain ranged from 8-10 on the numeric rating scale (NRS) despite multimodal pain therapy (non-steroid anti-rheumatics, opioids, physiotherapy, acupuncture). A paravertebral trial injection was performed preoperatively on the laminae of the thoracic vertebrae Th 2-Th 4. As the patient responded well, a paravertebral catheter was inserted close to Th 4 directly before the revision operation took place the following day. The case study describes the possibilities of eliminating pain segmentally in the axilla and an alternative technique to a paravertebral block (lamina technique).
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Affiliation(s)
- G Pfeiffer
- Abteilung für Anästhesie und Schmerztherapie, Triamed Kreisklinik Bad Aibling, Germany.
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Bläsing OE, Gibon Y, Günther M, Höhne M, Morcuende R, Osuna D, Thimm O, Usadel B, Scheible WR, Stitt M. Sugars and circadian regulation make major contributions to the global regulation of diurnal gene expression in Arabidopsis. Plant Cell 2005; 17:3257-81. [PMID: 16299223 PMCID: PMC1315368 DOI: 10.1105/tpc.105.035261] [Citation(s) in RCA: 473] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The diurnal cycle strongly influences many plant metabolic and physiological processes. Arabidopsis thaliana rosettes were harvested six times during 12-h-light/12-h-dark treatments to investigate changes in gene expression using ATH1 arrays. Diagnostic gene sets were identified from published or in-house expression profiles of the response to light, sugar, nitrogen, and water deficit in seedlings and 4 h of darkness or illumination at ambient or compensation point [CO(2)]. Many sugar-responsive genes showed large diurnal expression changes, whose timing matched that of the diurnal changes of sugars. A set of circadian-regulated genes also showed large diurnal changes in expression. Comparison of published results from a free-running cycle with the diurnal changes in Columbia-0 (Col-0) and the starchless phosphoglucomutase (pgm) mutant indicated that sugars modify the expression of up to half of the clock-regulated genes. Principle component analysis identified genes that make large contributions to diurnal changes and confirmed that sugar and circadian regulation are the major inputs in Col-0 but that sugars dominate the response in pgm. Most of the changes in pgm are triggered by low sugar levels during the night rather than high levels in the light, highlighting the importance of responses to low sugar in diurnal gene regulation. We identified a set of candidate regulatory genes that show robust responses to alterations in sugar levels and change markedly during the diurnal cycle.
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Affiliation(s)
- Oliver E Bläsing
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany.
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Bläsing OE, Gibon Y, Günther M, Höhne M, Morcuende R, Osuna D, Thimm O, Usadel B, Scheible WR, Stitt M. Sugars and circadian regulation make major contributions to the global regulation of diurnal gene expression in Arabidopsis. Plant Cell 2005; 17:3257-3281. [PMID: 16299223 DOI: 10.1105/tpc.105.035261.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The diurnal cycle strongly influences many plant metabolic and physiological processes. Arabidopsis thaliana rosettes were harvested six times during 12-h-light/12-h-dark treatments to investigate changes in gene expression using ATH1 arrays. Diagnostic gene sets were identified from published or in-house expression profiles of the response to light, sugar, nitrogen, and water deficit in seedlings and 4 h of darkness or illumination at ambient or compensation point [CO(2)]. Many sugar-responsive genes showed large diurnal expression changes, whose timing matched that of the diurnal changes of sugars. A set of circadian-regulated genes also showed large diurnal changes in expression. Comparison of published results from a free-running cycle with the diurnal changes in Columbia-0 (Col-0) and the starchless phosphoglucomutase (pgm) mutant indicated that sugars modify the expression of up to half of the clock-regulated genes. Principle component analysis identified genes that make large contributions to diurnal changes and confirmed that sugar and circadian regulation are the major inputs in Col-0 but that sugars dominate the response in pgm. Most of the changes in pgm are triggered by low sugar levels during the night rather than high levels in the light, highlighting the importance of responses to low sugar in diurnal gene regulation. We identified a set of candidate regulatory genes that show robust responses to alterations in sugar levels and change markedly during the diurnal cycle.
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Affiliation(s)
- Oliver E Bläsing
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany.
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Pusch D, Oh DY, Wolf S, Dumke R, Schröter-Bobsin U, Höhne M, Röske I, Schreier E. Detection of enteric viruses and bacterial indicators in German environmental waters. Arch Virol 2005; 150:929-47. [PMID: 15645371 DOI: 10.1007/s00705-004-0467-8] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2004] [Accepted: 11/11/2004] [Indexed: 11/28/2022]
Abstract
A German mining lake and the supplying surface waters, which are located downstream of a sewage plant, were examined regarding their microbiological and virological quality. Between October 2002 and September 2003, specific PCR methods were used to determine the occurrence of enteric viruses in 123 water specimens drawn at different sites downstream of the waste water treatment plant and in 9 samples from the sewage plant influent. Detection rates in sewage plant effluents and surface water samples depended on sampling sites and were: 29-76% for enterovirus (EntV), 24-42% (astrovirus, AstV), 15-53% (norovirus, NV), 3-24% (rotavirus, RoV), 5-20% (hepatitis A virus, HAV) and 20% (adenovirus, AdV). AstV genome load of selected samples was between 3.7 x 10(3) to 1.2 x 10(8) genome equivalents per liter (gen.equ./l), depending on sampling location; NV average genome load ranged from 1.8 x 10(4) to 9.7 x 10(5) gen.equ./l. Cell culture methods showed that three out of 18 PCR positive samples contained infectious EntV. Even though microbiological parameters such as Escherichia coli, enterococci and coliphages indicated acceptable microbiological water quality, the virological data of this study suggest the possibility that surface waters may be a source for enteric viral infections.
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Affiliation(s)
- D Pusch
- Robert Koch-Institute, Berlin, Germany
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Gibon Y, Blaesing OE, Hannemann J, Carillo P, Höhne M, Hendriks JHM, Palacios N, Cross J, Selbig J, Stitt M. A Robot-based platform to measure multiple enzyme activities in Arabidopsis using a set of cycling assays: comparison of changes of enzyme activities and transcript levels during diurnal cycles and in prolonged darkness. Plant Cell 2004; 16:3304-25. [PMID: 15548738 PMCID: PMC535875 DOI: 10.1105/tpc.104.025973] [Citation(s) in RCA: 385] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2004] [Accepted: 09/03/2004] [Indexed: 05/17/2023]
Abstract
A platform has been developed to measure the activity of 23 enzymes that are involved in central carbon and nitrogen metabolism in Arabidopsis thaliana. Activities are assayed in optimized stopped assays and the product then determined using a suite of enzyme cycling assays. The platform requires inexpensive equipment, is organized in a modular manner to optimize logistics, calculates results automatically, combines high sensitivity with throughput, can be robotized, and has a throughput of three to four activities in 100 samples per person/day. Several of the assays, including those for sucrose phosphate synthase, ADP glucose pyrophosphorylase (AGPase), ferredoxin-dependent glutamate synthase, glycerokinase, and shikimate dehydrogenase, provide large advantages over previous approaches. This platform was used to analyze the diurnal changes of enzyme activities in wild-type Columbia-0 (Col-0) and the starchless plastid phosphoglucomutase (pgm) mutant, and in Col-0 during a prolongation of the night. The changes of enzyme activities were compared with the changes of transcript levels determined with the Affymetrix ATH1 array. Changes of transcript levels typically led to strongly damped changes of enzyme activity. There was no relation between the amplitudes of the diurnal changes of transcript and enzyme activity. The largest diurnal changes in activity were found for AGPase and nitrate reductase. Examination of the data and comparison with the literature indicated that these are mainly because of posttranslational regulation. The changes of enzyme activity are also strongly delayed, with the delay varying from enzyme to enzyme. It is proposed that enzyme activities provide a quasi-stable integration of regulation at several levels and provide useful data for the characterization and diagnosis of different physiological states. As an illustration, a decision tree constructed using data from Col-0 during diurnal changes and a prolonged dark treatment was used to show that, irrespective of the time of harvest during the diurnal cycle, the pgm mutant resembles a wild-type plant that has been exposed to a 3 d prolongation of the night.
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Affiliation(s)
- Yves Gibon
- Max Planck Institute of Molecular Plant Physiology, Science Park Golm, 14476 Golm-Potsdam, Germany.
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Abstract
This is a report about an inadvertent intravenous infusion of 380 mg ropivacaine in a 84-year-old patient over a period of 1.75 h. The level of serum ropivacaine measured immediately after the end of the infusion as well as 2 h and 7 h later, was initially in the lower toxic range (free concentration of 0.48 micro g/ml). The patient showed no symptoms of intoxication neither clinically nor during the technical examinations (EEG, ECG). This case confirms the wide therapeutic range of ropivacaine.
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Affiliation(s)
- G Pfeiffer
- Klinik für Anästhesie, Intensivmedizin und Schmerztherapie, Behandlungszentrum Vogtareuth.
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Gibon Y, Bläsing OE, Palacios-Rojas N, Pankovic D, Hendriks JHM, Fisahn J, Höhne M, Günther M, Stitt M. Adjustment of diurnal starch turnover to short days: depletion of sugar during the night leads to a temporary inhibition of carbohydrate utilization, accumulation of sugars and post-translational activation of ADP-glucose pyrophosphorylase in the following light period. Plant J 2004; 39:847-62. [PMID: 15341628 DOI: 10.1111/j.1365-313x.2004.02173.x] [Citation(s) in RCA: 253] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A larger proportion of the fixed carbon is retained as starch in the leaf in short days, providing a larger store to support metabolism and carbon export during the long night. The mechanisms that facilitate this adjustment of the sink-source balance are unknown. Starchless pgm mutants were analysed to discover responses that are triggered when diurnal starch turnover is disturbed. Sugars accumulated to high levels during the day, and fell to very low levels by the middle of the night. Sugars rose rapidly in the roots and rosette after illumination, and decreased later in the light period. Global transcript profiling revealed only small differences between pgm and Col0 at the end of the day but large differences at the end of the night, when pgm resembled Col0 after a 4-6 h prolongation of the night and many genes required for biosynthesis and growth were repressed [Plant J. 37 (2004) 914]. It is concluded that transient sugar depletion at the end of the night inhibits carbon utilization at the start of the ensuing light period. A second set of experiments investigated the stimulation of starch synthesis in response to short days in wild-type Col0. In short days, sugars were very low in the roots and rosette at the end of the dark period, and after illumination accumulated rapidly in both organs to levels that were higher than in long days. The response resembles pgm, except that carbohydrate accumulated in the leaf as starch instead of sugars. A similar response was found after transfer from long to short days. Inclusion of sugar in the rooting medium attenuated the stimulation of starch synthesis. Post-translational activation of ADP-glucose pyrophosphorylase (AGPase) was increased in pgm, and in Col0 in short days. It is concluded that starch synthesis is stimulated in short day conditions because sugar depletion at the end of the night triggers a temporary inhibition of growth and carbohydrate utilization in the first part of the light period, leading to transient accumulation of sugar and activation of AGPase.
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Affiliation(s)
- Yves Gibon
- Max Planck Institute of Molecular Plant Physiology, Science Park Golm, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany
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Pascu M, Martus P, Höhne M, Wiedenmann B, Hopf U, Schreier E, Berg T. Sustained virological response in hepatitis C virus type 1b infected patients is predicted by the number of mutations within the NS5A-ISDR: a meta-analysis focused on geographical differences. Gut 2004; 53:1345-51. [PMID: 15306598 PMCID: PMC1774214 DOI: 10.1136/gut.2003.031336] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND AIMS There is growing evidence that the response of hepatitis C virus (HCV) genotype 1b infected patients towards interferon (IFN) therapy is influenced by the number of mutations within the carboxy terminal region of the NS5A gene, the interferon sensitivity determining region (ISDR). PATIENTS AND METHODS In order to attain better insight into this correlation, a file comprising published data on ISDR strains from 1230 HCV genotype 1b infected patients, mainly from Japan and Europe, was constructed and analysed by logistic regression. Sustained virological response (SVR) was defined as negative HCV RNA six months after treatment. RESULTS The distribution of wild-, intermediate-, and mutant-type ISDR sequences differed significantly between Japanese (n = 655) (44.1%, 37.6%, and 18.3%) and European patients (n = 525) (24.8%, 63.4%, and 11.8%; p<0.001). There was a significant positive correlation between the number of ISDR mutations and SVR rate, irrespective of geographical region. The likelihood of SVR with each additional mutation within the ISDR was considerably more pronounced in Japanese compared with European patients (odds ratios 1.82 v 1.39; p<0.001). Pretreatment viraemia of <6.6 log copies/ml and ISDR mutant-type infection was associated with an SVR rate of 97.1% in Japanese patients but only 52.5% in European patients. Pretreatment viraemia was a stronger predictor of SVR than ISDR mutation number in Japanese patients whereas in European patients both parameters had similar predictive power. CONCLUSION These data support the concept that mutant-type ISDR strains may represent a subtype within genotype 1b with a more favourable response towards IFN therapy.
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Affiliation(s)
- M Pascu
- Medizinische Klinik m S Hepatologie und Gastroenterologie, Charité, Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin, Germany.
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Höhne M, Schreier E. Detection and characterization of norovirus outbreaks in Germany: application of a one-tube RT-PCR using a fluorogenic real-time detection system. J Med Virol 2004; 72:312-9. [PMID: 14695676 DOI: 10.1002/jmv.10573] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Outbreaks of gastroenteritis caused by Norovirus are an increasing public health problem worldwide. The virus is transmitted by contaminated food and by person-to-person. In Germany, a new health reporting system including Norovirus infections has been introduced in 2001. Norovirus outbreaks (73%) diagnosed in our lab occurred in the first half of the year. Phylogenetic analysis shows that 90% belonged to genogroup II (GGII) with the majority related to prototypes Lordsdale/93 and Tarragona/2001. To date, PCR is the most sensitive and specific method for the detection but several procedures are needed to evaluate the amplification product. To minimize the risk of product carryover, a fast and simple procedure with a minimal number of steps are required. A one-tube RT-PCR method is described using the real-time TaqMan-PCR system. Primer sets and probes for both genogroup I (GGI) and genogroup II (GGII) sequences were developed. The specificity and sensitivity of this method was evaluated on 70 Norovirus positive stool samples of 70 outbreaks in Germany and 34 European samples by comparing the detection rate to those of an in-house RT-nested PCR. Overall, 93% of the PCR positive samples have been detected by the TaqMan-PCR including isolates of four different GGI and seven different GGII genotypes. Using plasmid standards for quantitation, virus loads between 10(2) and 10(10) genomic equivalents/ml stool suspension were found. The advantages of the one-step RT/TaqMan-PCR system for detection and quantitation of Norovirus are the high throughput of clinical samples and a decrease of the risk of contamination.
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Affiliation(s)
- M Höhne
- Department of Molecular Epidemiology, of Viral Pathogens, Robert Koch-Institute, Berlin, Germany.
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Jansen A, Beyer A, Brandt C, Höhne M, Schreier E, Schulzke J, Zeitz M, Schneider T. Die Norovirus-Epidemie in Berlin - Klinik, Epidemiologie und Prävention. Z Gastroenterol 2004; 42:311-6. [PMID: 15095121 DOI: 10.1055/s-2004-812908] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
INTRODUCTION During the winter 2002/2003, an increased number of outbreaks of acute gastroenteritis caused by norovirus was reported from Germany, some other European countries and the USA. In this study, the epidemiological and clinical features of the Berlin norovirus outbreak were investigated in order to identify the reasons for the spread of norovirus gastroenteritis and possible control measures. METHODS Cases and spread of norovirus infection in eleven long-term care facilities and a university hospital in Berlin were monitored from October 2002 to February 2003. To investigate the symptomatology and routes of transmission, a retrospective and interview-based study of infected staff members was performed. RESULTS Norovirus outbreaks in eleven long-term care facilities affected 314 patients (attack rate: 28.3 %, rate of hospitalisation: 20.7 %). 219 persons were affected in the hospital, during a period of four months. Sequence analysis revealed the circulation of Norovirus genogroup II (Grimsby-like viruses). The mean duration of symptoms was 69 hours. The duration of outbreaks on specific wards was negatively correlated with the time of returning to work (mean: 1.8 days) of the staff members after the disease. DISCUSSION This report demonstrates the potential of norovirus to cause large outbreaks by person to person transmission. Spread by aerosols generated by vomiting and environmental contamination seem to be particular important in institutional settings. The duration of symptoms was longer than reported previously, reflecting a possible increased virulence. Besides this, the outbreak was facilitated by insufficient preventive measures.
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Affiliation(s)
- A Jansen
- Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, I. Medizinische Klinik - Gastroenterologie/Infektiologie/Rheumatologie, Berlin.
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Stark K, Poggensee G, Höhne M, Bienzle U, Kiwelu I, Schreier E. Seroepidemiology of TT virus, GBC-C/HGV, and hepatitis viruses B, C, and E among women in a rural area of Tanzania. J Med Virol 2001. [PMID: 11074483 DOI: 10.1002/1096-9071(200012)62:4<524::aid-jmv19>3.0.co;2-n] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The seroprevalence and determinants of hepatitis B, C, and E virus infection, and of GBV-C/hepatitis G virus and TT virus infection were investigated among women from a rural area of northeastern Tanzania. High seroprevalence rates were found for TTV (74%), HBV (74%), and GBV-C/HGV (35%), whereas 7% of the women had evidence of HCV and HEV infection. The majority of TTV DNA sequences in the study population belonged to the genotypes 1 or 2. One sequence seems to represent a new subtype of genotype 4. The GBV-C/HGV sequences either belonged to the genomic Group 1b or to the recently described Group 4. In multivariate analysis, the detection of TTV DNA was associated significantly with a larger number of children in the household and with older age. A history of injections of contraceptive hormones was an independent risk factor for HCV infection. The findings on TTV are consistent with fecal-oral transmission, and recurrent infections may occur in adults.
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Affiliation(s)
- K Stark
- Institute of Tropical Medicine, Charité, Humboldt University of Berlin, Berlin, Germany.
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Abstract
The seroprevalence and determinants of hepatitis B, C, and E virus infection, and of GBV-C/hepatitis G virus and TT virus infection were investigated among women from a rural area of northeastern Tanzania. High seroprevalence rates were found for TTV (74%), HBV (74%), and GBV-C/HGV (35%), whereas 7% of the women had evidence of HCV and HEV infection. The majority of TTV DNA sequences in the study population belonged to the genotypes 1 or 2. One sequence seems to represent a new subtype of genotype 4. The GBV-C/HGV sequences either belonged to the genomic Group 1b or to the recently described Group 4. In multivariate analysis, the detection of TTV DNA was associated significantly with a larger number of children in the household and with older age. A history of injections of contraceptive hormones was an independent risk factor for HCV infection. The findings on TTV are consistent with fecal-oral transmission, and recurrent infections may occur in adults.
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Affiliation(s)
- K Stark
- Institute of Tropical Medicine, Charité, Humboldt University of Berlin, Berlin, Germany.
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Berg T, Mas Marques A, Höhne M, Wiedenmann B, Hopf U, Schreier E. Mutations in the E2-PePHD and NS5A region of hepatitis C virus type 1 and the dynamics of hepatitis C viremia decline during interferon alfa treatment. Hepatology 2000; 32:1386-95. [PMID: 11093746 DOI: 10.1053/jhep.2000.20527] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Both a double-stranded RNA-dependent protein kinase (PKR)-phosphorylation homology domain (PePHD) within the E2 protein and a PKR-binding domain within the nonstructural 5A (NS5A) protein of hepatitis C virus (HCV) genotype 1 isolates inhibit the function of the interferon alfa (IFN-alpha)-induced antiviral effector protein PKR in vitro. We investigated whether the mutational pattern of the E2 region (codons 618-681, including PePHD) of 81 HCV genotype 1-infected patients (HCV-1b [n = 54], HCV-1a [n = 27]) influences the response to IFN-alpha. Initial viral decline (DeltaHCV RNA) was determined at week 1 hereby covering the effector reactions of IFN-alpha-mediated first phase and the immune-mediated second phase. DeltaHCV RNA less than 50% (group 1); DeltaHCV RNA greater than 50% but less than 90% (group 2); and DeltaHCV RNA > or =90% (group 3) were differentiated. The PePHD region was highly conserved; the few mutations (5 patients) did not correlate with DeltaHCV RNA or sustained virologic response to IFN-alpha. Within the flanking regions before and after PePHD (codons 618-681) 72 of 81 patients (89%) had 2.6+/-0.17 mutations (median, 3; range, 1-8) that did not correlate with treatment response. Sequence analysis of the NS5A protein (codons 2,209-2,274, including interferon sensitivity determining region [ISDR]) in 39 of 81 patients showed a higher mean number of mutations in the ISDR (codons 2,209-2,248) in groups 2 (1.28+/- 0.43 [n = 18]) and 3 (1.89+/-0.54 [n = 9]) than in group 1 (0.67+/- 0.19 [n = 12]; P =.049 group 1 vs. 3) and a mutant type ISDR (e.g., > or =4 mutations) was significantly more frequent in sustained virologic responders than in nonresponders or relapsers (2 of 4 [50%] vs. 2 of 35 [6%]; P =.045). Thus, NS5A appears to be functionally relevant in IFN-alpha-induced effector reactions.
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Affiliation(s)
- T Berg
- Medizinische Klinik mit Schwerpunkt Hepatologie und Gastroenterologie, Universitätsklinikum Charité, Campus Virchow-Klinikum, Humboldt-Universität, Berlin, Germany.
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Höhne M, Schreier E. Lebensmittelassoziierte Virusinfektionen. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2000. [DOI: 10.1007/s001030050354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Hause B, Weichert H, Höhne M, Kindl H, Feussner I. Expression of cucumber lipid-body lipoxygenase in transgenic tobacco: lipid-body lipoxygenase is correctly targeted to seed lipid bodies. Planta 2000; 210:708-14. [PMID: 10805441 DOI: 10.1007/s004250050671] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
A particular isoform of lipoxygenase (LOX, EC 1.13.11.12) localized on lipid bodies has been shown by earlier investigations to play a role during seed germination in initiating the mobilization of triacylglycerols. On lipid bodies of germinating cucumber (Cucumis sativus L.) seedlings, the modification of linoleoyl moieties by this LOX precedes the hydrolysis of the ester bonds. We analyzed the expression and intracellular location of this particular LOX form in leaves and seeds of tobacco (Nicotiana tabacum L.) transformed with one construct coding for cucumber lipid-body LOX and one construct coding for cucumber LOX fused with a hemagglutinin epitope. In both tissues, the amount of lipid-body LOX was clearly detectable. Biochemical analysis revealed that in mature seeds the foreign LOX was targeted to lipid bodies, and the preferred location of the LOX on lipid bodies was verified by immunofluorescence microscopy. Cells of the endosperm and of the embryo exhibited fluorescence based on the immunodecoration of LOX protein whereas very weak fluorescent label was visible in seeds of untransformed control plants. Further cytochemical analysis of transformed plants showed that the LOX protein accumulated in the cytoplasm when green leaves lacking lipid bodies were analyzed. Increased LOX activity was shown in young leaves of transformed plants by an increase in the amounts of endogenous (2E)-hexenal and jasmonic acid.
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Affiliation(s)
- B Hause
- Institut für Pflanzenbiochemie, Halle, Germany.
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May C, Höhne M, Gnau P, Schwennesen K, Kindl H. The N-terminal beta-barrel structure of lipid body lipoxygenase mediates its binding to liposomes and lipid bodies. Eur J Biochem 2000; 267:1100-9. [PMID: 10672019 DOI: 10.1046/j.1432-1327.2000.01105.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Phospholipase A2 and a particular isoform of lipoxygenase are synthesized and transferred to lipid bodies during the stage of triacylglycerol mobilization in germinating cucumber seedlings. Lipid body lipoxygenase (LBLOX) is post-translationally transported to lipid bodies without proteolytic modification. Fractionation of homogenates from cucumber cotyledons or transgenic tobacco leaves expressing LBLOX showed that a small but significant amount was detectable in the microsomal fraction. A beta-barrel-forming N-terminal domain in the structure of LBLOX, as deduced from sequence data, was shown to be crucial for selective intracellular transport from the cytosol to lipid bodies. Although a specific signal sequence for targeting protein domains to the lipid bodies could not be established, it was evident that the beta-barrel represents a membrane-binding domain that is functionally comparable with the C2 domains of mammalian phospholipases. The intact beta-barrel of LBLOX was demonstrated to be sufficient to target in vitro a fusion protein of LBLOX beta-barrel with glutathione S-transferase (GST) to lipid bodies. In addition, binding experiments on liposomes using lipoxygenase isoforms, LBLOX deletions and the GST-fusion protein confirmed the role of the beta-barrel as the membrane-targeting domain. In this respect, the cucumber LBLOX differs from cytosolic isoforms in cucumber and from the soybean LOX-1. When the beta-barrel of LBLOX was destroyed by insertion of an additional peptide sequence, its ability to target proteins to membranes was abolished.
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Affiliation(s)
- C May
- Fachbereich Chemie der Philipps-Universität, Marburg, Germany
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Berg T, Schreier E, Heuft HG, Höhne M, Bechstein WO, Leder K, Hopf U, Neuhaus P, Wiedenmann B. Occurrence of a novel DNA virus (TTV) infection in patients with liver diseases and its frequency in blood donors. J Med Virol 1999. [PMID: 10440818 DOI: 10.1002/(sici)1096-9071(199909)59:1<117::aid-jmv19>3.0.co;2-i] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A novel DNA virus (TTV) was identified recently in Japanese patients with posttransfusion hepatitis non-A-E and has been implicated as a cause of acute and chronic liver diseases of unknown etiology in some patients. The frequency of TTV infections was investigated in 284 blood donors, 105 patients with different liver disorders before and after liver transplantation (OLT), as well as in 64 patients with chronic hepatitis C who received antiviral therapy. TTV infections were found more frequently by nested-PCR in patients with liver disorders (15%) as compared to blood donors (7%). TTV occurred independently of the aetiology of the liver disease (e.g., cryptogenic cirrhosis [12.5%], alcoholic cirrhosis [16%], fulminant hepatic failure non-A-E [35%], and chronic hepatitis C [12.5%]; p=n.s.). After OLT, a high rate of TTV de novo infections (44%) was observed. However, TTV viremia after OLT (in 56 out of the 105 patients) was not associated with graft hepatitis. Analysis of patients with chronic hepatitis C coinfected with TTV who have been treated with interferon alpha alone or in combination with ribavirin revealed that TTV is an interferon-sensitive virus. Phylogenetic analysis of TTV sequences suggest that at least four different genotypes and several subtypes exist in Germany. In conclusion, the high prevalence of TTV infections observed in patients with parenteral risk factors is an argument in favour of transmission of the virus via blood and blood products. A relevant hepatitis-inducing capacity of TTV, however, seems unlikely, considering the observation that in the majority of patients, TTV infection after OLT was not accompanied by graft hepatitis.
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Affiliation(s)
- T Berg
- Medizinische Klinik mit Schwerpunkt Hepatologie/Gastroenterologie, Universitätsklinikum Charité, Humboldt-Universität, Berlin, Germany.
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Berg T, Schreier E, Heuft HG, Höhne M, Bechstein WO, Leder K, Hopf U, Neuhaus P, Wiedenmann B. Occurrence of a novel DNA virus (TTV) infection in patients with liver diseases and its frequency in blood donors. J Med Virol 1999; 59:117-21. [PMID: 10440818 DOI: 10.1002/(sici)1096-9071(199909)59:1<117::aid-jmv19>3.0.co;2-i] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A novel DNA virus (TTV) was identified recently in Japanese patients with posttransfusion hepatitis non-A-E and has been implicated as a cause of acute and chronic liver diseases of unknown etiology in some patients. The frequency of TTV infections was investigated in 284 blood donors, 105 patients with different liver disorders before and after liver transplantation (OLT), as well as in 64 patients with chronic hepatitis C who received antiviral therapy. TTV infections were found more frequently by nested-PCR in patients with liver disorders (15%) as compared to blood donors (7%). TTV occurred independently of the aetiology of the liver disease (e.g., cryptogenic cirrhosis [12.5%], alcoholic cirrhosis [16%], fulminant hepatic failure non-A-E [35%], and chronic hepatitis C [12.5%]; p=n.s.). After OLT, a high rate of TTV de novo infections (44%) was observed. However, TTV viremia after OLT (in 56 out of the 105 patients) was not associated with graft hepatitis. Analysis of patients with chronic hepatitis C coinfected with TTV who have been treated with interferon alpha alone or in combination with ribavirin revealed that TTV is an interferon-sensitive virus. Phylogenetic analysis of TTV sequences suggest that at least four different genotypes and several subtypes exist in Germany. In conclusion, the high prevalence of TTV infections observed in patients with parenteral risk factors is an argument in favour of transmission of the virus via blood and blood products. A relevant hepatitis-inducing capacity of TTV, however, seems unlikely, considering the observation that in the majority of patients, TTV infection after OLT was not accompanied by graft hepatitis.
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Affiliation(s)
- T Berg
- Medizinische Klinik mit Schwerpunkt Hepatologie/Gastroenterologie, Universitätsklinikum Charité, Humboldt-Universität, Berlin, Germany.
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Höhne M, Thaler S, Dudda JC, Groner B, Schnierle BS. Truncation of the human immunodeficiency virus-type-2 envelope glycoprotein allows efficient pseudotyping of murine leukemia virus retroviral vector particles. Virology 1999; 261:70-8. [PMID: 10441556 DOI: 10.1006/viro.1999.9847] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The incorporation of human immunodeficiency virus-type-2 (HIV-2) envelope glycoprotein into murine leukemia virus (MuLV) particles was studied in a transient transfection packaging cell system. We observed that wild-type HIV-2 envelope protein or a frameshift mutant with 187 unrelated carboxyl-terminal residues did not allow the formation of infectious retroviral particles. In view of recent findings that an HIV-1 envelope protein variant with a shortened cytoplasmic domain was incorporated into MuLV particles, we constructed carboxyl-terminal truncations of the HIV-2 envelope protein. An envelope variant with 18 cytoplasmic amino acids formed only very few viral pseudotypes. The further removal of an additional 11 amino acids allowed the efficient pseudotyping of MuLV particles. As with the HIV-1 envelope protein, an HIV-2 envelope variant with 7 cytoplasmic amino acids was incorporated into functional MuLV particles. The pseudotyped vectors obtained are able to infect human CD4/CXCR4-expressing cells. Cell lines expressing human CD4 and other coreceptors could not be infected. This retroviral vector will prove useful for the study of HIV infection events mediated by the HIV-2 envelope glycoproteins, as well as for the targeting of CD4+ cells in the context of gene therapy of AIDS.
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Affiliation(s)
- M Höhne
- Institute for Experimental Cancer Research, Tumor Biology Center, Breisacherstrasse 117, Freiburg, D-79106, Germany
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