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31.
32.
Sandra Blanco Sabine Dietmann Joana V Flores Shobbir Hussain Claudia Kutter Peter Humphreys Margus Lukk Patrick Lombard Lucas Treps Martyna Popis Stefanie Kellner Sabine M Hölter Lillian Garrett Wolfgang Wurst Lore Becker Thomas Klopstock Helmut Fuchs Valerie Gailus‐Durner Martin Hrabĕ de Angelis Ragnhildur T Káradóttir Mark Helm Jernej Ule Joseph G Gleeson Duncan T Odom Michaela Frye 《The EMBO journal》2014,33(18):2020-2039
33.
Green light: a signal to slow down or stop 总被引:3,自引:1,他引:3
Light has a profound effect on plant growth and development. Red and blue light best drive photosynthetic metabolism, so it is no surprise that these light qualities are particularly efficient in advancing the developmental characteristics associated with autotrophic growth habits. Photosynthetically inefficient light qualities also impart important environmental information to a developing plant. For example, far-red light reverses the effect of phytochromes, leading to changes in gene expression, plant architecture, and reproductive responses. Recent evidence shows that green light also has discrete effects on plant biology, and the mechanisms that sense this light quality are now being elucidated. Green light has been shown to affect plant processes via cryptochrome-dependent and cryptochrome-independent means. Generally, the effects of green light oppose those directed by red and blue wavebands. This review examines the literature where green light has been implicated in physiological or developmental outcomes, many not easily attributable to known sensory systems. Here roles of green light in the regulation of vegetative development, photoperiodic flowering, stomatal opening, stem growth modulation, chloroplast gene expression and plant stature are discussed, drawing from data gathered over the last 50 years of plant photobiological research. Together these reports support a conclusion that green light sensory systems adjust development and growth in orchestration with red and blue sensors. 相似文献
34.
Sebastian Schneider Arno Schintlmeister Manuel Becana Michael Wagner Dagmar Woebken Stefanie Wienkoop 《Plant, cell & environment》2019,42(4):1180-1189
Legume–rhizobia symbioses play a major role in food production for an ever growing human population. In this symbiosis, dinitrogen is reduced (“fixed”) to ammonia by the rhizobial nitrogenase enzyme complex and is secreted to the plant host cells, whereas dicarboxylic acids derived from photosynthetically produced sucrose are transported into the symbiosomes and serve as respiratory substrates for the bacteroids. The symbiosome membrane contains high levels of SST1 protein, a sulfate transporter. Sulfate is an essential nutrient for all living organisms, but its importance for symbiotic nitrogen fixation and nodule metabolism has long been underestimated. Using chemical imaging, we demonstrate that the bacteroids take up 20‐fold more sulfate than the nodule host cells. Furthermore, we show that nitrogenase biosynthesis relies on high levels of imported sulfate, making sulfur as essential as carbon for the regulation and functioning of symbiotic nitrogen fixation. Our findings thus establish the importance of sulfate and its active transport for the plant–microbe interaction that is most relevant for agriculture and soil fertility. 相似文献
35.
Ribeiro FM Black SA Prado VF Rylett RJ Ferguson SS Prado MA 《Journal of neurochemistry》2006,99(1):1-12
Maintenance of acetylcholine (ACh) synthesis depends on the activity of the high-affinity choline transporter (CHT1), which is responsible for the reuptake of choline from the synaptic cleft into presynaptic neurons. In this review, we discuss the current understanding of mechanisms involved in the cellular trafficking of CHT1. CHT1 protein is mainly found in intracellular organelles, such as endosomal compartments and synaptic vesicles. The presence of CHT1 at the plasma membrane is limited by rapid endocytosis of the transporter in clathrin-coated pits in a mechanism dependent on a dileucine-like motif present in the carboxyl-terminal region of the transporter. The intracellular pool of CHT1 appears to constitute a reserve pool of transporters, important for maintenance of cholinergic neurotransmission. However, the physiological basis of the presence of CHT1 in intracellular organelles is not fully understood. Current knowledge about CHT1 indicates that stimulated and constitutive exocytosis, in addition to endocytosis, will have major consequences for regulating choline uptake. Future investigations of CHT1 trafficking should elucidate such regulatory mechanisms, which may aid in understanding the pathophysiology of diseases that affect cholinergic neurons, such as Alzheimer's disease. 相似文献
36.
Benjamin Zwirzitz Sarah Thalguter Stefanie U. Wetzels Beatrix Stessl Martin Wagner Evelyne Selberherr 《Microbial biotechnology》2022,15(5):1392-1403
Raw meat sausage represents a unique ecological niche rich in nutrients for microbial consumption, making it particularly vulnerable to microbial spoilage. Starter cultures are applied to improve product stability and safety as well as flavour characteristics. However, the influence of starter cultures on microbial community assembly and succession throughout the fermentation process is largely unknown. In particular the effect on the fungal community has not yet been explored. We evaluate the microbiological status of four different raw meat sausages using high-throughput 16S rRNA gene and ITS2 gene sequencing. The objective was to study temporal changes of microbial composition during the fermentation process and to identify potential keystone species that play an important role within the microbial community. Our results suggest that fungi assigned to the species Debaryomyces hansenii and Alternaria alternata play a key role in microbial community dynamics during fermentation. In addition, bacteria related to the starter culture Lactobacillus sakei and the spoilage-associated genera Acinetobacter, Pseudomonas and Psychrobacter are central components of the microbial ecosystem in raw fermented sausages. Elucidating the exact role and interactions of these microorganisms has the potential to have direct impacts on the quality and safety of fermented foods. 相似文献
37.
Stefanie Wagner Frédéric Lagane Andaine Seguin‐Orlando Mikkel Schubert Thibault Leroy Erwan Guichoux Emilie Chancerel Inger Bech‐Hebelstrup Vincent Bernard Cyrille Billard Yves Billaud Matthias Bolliger Christophe Croutsch Katarina Čufar Frédérique Eynaud Karl Uwe Heussner Joachim Köninger Fabien Langenegger Frédéric Leroy Christine Lima Nicoletta Martinelli Garry Momber André Billamboz Oliver Nelle Antoni Palomo Raquel Piqué Marianne Ramstein Roswitha Schweichel Harald Stäuble Willy Tegel Xavier Terradas Florence Verdin Christophe Plomion Antoine Kremer Ludovic Orlando 《Molecular ecology》2018,27(5):1138-1154
Reconstructing the colonization and demographic dynamics that gave rise to extant forests is essential to forecasts of forest responses to environmental changes. Classical approaches to map how population of trees changed through space and time largely rely on pollen distribution patterns, with only a limited number of studies exploiting DNA molecules preserved in wooden tree archaeological and subfossil remains. Here, we advance such analyses by applying high‐throughput (HTS) DNA sequencing to wood archaeological and subfossil material for the first time, using a comprehensive sample of 167 European white oak waterlogged remains spanning a large temporal (from 550 to 9,800 years) and geographical range across Europe. The successful characterization of the endogenous DNA and exogenous microbial DNA of 140 (~83%) samples helped the identification of environmental conditions favouring long‐term DNA preservation in wood remains, and started to unveil the first trends in the DNA decay process in wood material. Additionally, the maternally inherited chloroplast haplotypes of 21 samples from three periods of forest human‐induced use (Neolithic, Bronze Age and Middle Ages) were found to be consistent with those of modern populations growing in the same geographic areas. Our work paves the way for further studies aiming at using ancient DNA preserved in wood to reconstruct the micro‐evolutionary response of trees to climate change and human forest management. 相似文献
38.
Stefanie Hartman Chen Jody L. Plank Smaranda Willcox Jack D. Griffith Tao-shih Hsieh 《PloS one》2014,9(1)
Although Blm and Top3α are known to form a minimal dissolvasome that can uniquely undo a double Holliday junction structure, the details of the mechanism remain unknown. It was originally suggested that Blm acts first to create a hemicatenane structure from branch migration of the junctions, followed by Top3α performing strand passage to decatenate the interlocking single strands. Recent evidence suggests that Top3α may also be important for assisting in the migration of the junctions. Using a mismatch-dHJ substrate (MM-DHJS) and eukaryotic Top1 (in place of Top3α), we show that the presence of a topoisomerase is required for Blm to substantially migrate a topologically constrained Holliday junction. When investigated by electron microscopy, these migrated structures did not resemble a hemicatenane. However, when Blm is together with Top3α, the dissolution reaction is processive with no pausing at a partially migrated structure. Potential mechanisms are discussed. 相似文献
39.
de Graaf DC De Vos P Heyndrickx M Van Trappen S Peiren N Jacobs FJ 《Journal of invertebrate pathology》2006,91(2):115-123
This study was initially aimed at developing a PCR-test to differentiate between the pathogenic agent of American foulbrood (Paenibacillus larvae subsp. larvae) and powdery-scale disease (P. larvae subsp. pulvifaciens) of the honeybee. The test was based on the "insert of clone 9" (iC9), referring to a cloned 1.9 kB HaeIII fragment that occurs only in the P. larvae subsp. larvae reference strains and possibly correlates with American foulbrood virulence. It was shown that an iC9-based PCR-test discriminates between the BCCM/LMG reference strains of both subspecies. However, the screening of 179 Belgian field strains revealed five isolates that gave no iC9-based amplicon, thus rather resembling to P. larvae subsp. pulvifaciens. In addition, they all produced acid from mannitol, a characteristic previously assigned to the pulvifaciens subspecies. Because the reference strains gave conflicting data, this carbohydrate acidification was not conclusive. Therefore, the exact taxonomic position of the five retained strains was determined by a polyphasic approach using SDS-PAGE, AFLP, and ERIC-based PCR. Four iC9-negative field strains could be identified as P. larvae subsp. larvae; the taxonomic position of the fifth field strain remained ambiguous. The latter was provisionally classified as a subspecies pulvifaciens strain on the basis of SDS-PAGE. The present paper demonstrates the existence of field strains that do not fit well in the subdivision of the species P. larvae into two subspecies. Knowing that only one of both subspecies represents the pathogenic agent of AFB, this is a serious obstacle for the diagnosis of this honeybee disease. 相似文献
40.
María Fernanda Lammoglia Cobo Julia Ritter Regina Gary Volkhard Seitz Josef Mautner Michael Aigner Simon Vlkl Stefanie Schaffer Stephanie Moi Anke Seegebarth Heiko Bruns Wolf Rsler Kerstin Amann Maike Büttner-Herold Steffen Hennig Andreas Mackensen Michael Hummel Andreas Moosmann Armin Gerbitz 《PLoS pathogens》2022,18(4)
Reconstitution of the T cell repertoire after allogeneic stem cell transplantation is a long and often incomplete process. As a result, reactivation of Epstein-Barr virus (EBV) is a frequent complication that may be treated by adoptive transfer of donor-derived EBV-specific T cells. We generated donor-derived EBV-specific T cells by stimulation with peptides representing defined epitopes covering multiple HLA restrictions. T cells were adoptively transferred to a patient who had developed persisting high titers of EBV after allogeneic stem cell transplantation for angioimmunoblastic T-cell lymphoma (AITL). T cell receptor beta (TCRβ) deep sequencing showed that the T cell repertoire of the patient early after transplantation (day 60) was strongly reduced and only very low numbers of EBV-specific T cells were detectable. Manufacturing and in vitro expansion of donor-derived EBV-specific T cells resulted in enrichment of EBV epitope-specific, HLA-restricted T cells. Monitoring of T cell clonotypes at a molecular level after adoptive transfer revealed that the dominant TCR sequences from peptide-stimulated T cells persisted long-term and established an EBV-specific TCR clonotype repertoire in the host, with many of the EBV-specific TCRs present in the donor. This reconstituted repertoire was associated with immunological control of EBV and with lack of further AITL relapse. 相似文献