bluuebunny/crossref_metadata_2025_split huggingface dataset:
Posttranscriptional Control of Gene Expression in Yeast
Authors: McCarthy John E. G. 
Published: December 2019

SUMMARYStudies of the budding yeast Saccharomyces cerevisiae have greatly advanced our understanding of the posttranscriptional steps of eukaryotic gene expression. Given the wide range of experimental tools applicable to S. cerevisiae and the recent determination of its complete genomic sequence, many of the key challenges of the posttranscriptional control field can be tackled particularly effectively by using this organism. This article reviews the current knowledge of the cellular components and mechanisms related to translation and mRNA decay, with the emphasis on the molecular basis for rate control and gene regulation. Recent progress in characterizing translation factors and their protein-protein and RNA-protein interactions has been rapid. Against the background of a growing body of structural information, the review discusses the thermodynamic and kinetic principles that govern the translation process. As in prokaryotic systems, translational initiation is a key point of control. Modulation of the activities of translational initiation factors imposes global regulation in the cell, while structural features of particular 5′ untranslated regions, such as upstream open reading frames and effector binding sites, allow for gene-specific regulation. Recent data have revealed many new details of the molecular mechanisms involved while providing insight into the functional overlaps and molecular networking that are apparently a key feature of evolving cellular systems. An overall picture of the mechanisms governing mRNA decay has only very recently begun to develop. The latest work has revealed new information about the mRNA decay pathways, the components of the mRNA degradation machinery, and the way in which these might relate to the translation apparatus. Overall, major challenges still to be addressed include the task of relating principles of posttranscriptional control to cellular compartmentalization and polysome structure and the role of molecular channelling in these highly complex expression systems.
Mechanisms of Arthropod Transmission of Plant and Animal Viruses
Authors: Gray Stewart M. , Banerjee Nanditta 
Published: December 2019

SUMMARYA majority of the plant-infecting viruses and many of the animal-infecting viruses are dependent upon arthropod vectors for transmission between hosts and/or as alternative hosts. The viruses have evolved specific associations with their vectors, and we are beginning to understand the underlying mechanisms that regulate the virus transmission process. A majority of plant viruses are carried on the cuticle lining of a vector’s mouthparts or foregut. This initially appeared to be simple mechanical contamination, but it is now known to be a biologically complex interaction between specific virus proteins and as yet unidentified vector cuticle-associated compounds. Numerous other plant viruses and the majority of animal viruses are carried within the body of the vector. These viruses have evolved specific mechanisms to enable them to be transported through multiple tissues and to evade vector defenses. In response, vector species have evolved so that not all individuals within a species are susceptible to virus infection or can serve as a competent vector. Not only are the virus components of the transmission process being identified, but also the genetic and physiological components of the vectors which determine their ability to be used successfully by the virus are being elucidated. The mechanisms of arthropod-virus associations are many and complex, but common themes are beginning to emerge which may allow the development of novel strategies to ultimately control epidemics caused by arthropod-borne viruses.
Protein Targeting to the Bacterial Cytoplasmic Membrane
Authors: Fekkes Peter , Driessen Arnold J. M. 
Published: December 2019

SUMMARY
Proteins that perform their activity within the cytoplasmic membrane or outside this cell boundary must be targeted to the translocation site prior to their insertion and/or translocation. In bacteria, several targeting routes are known; the SecB- and the signal recognition particle-dependent pathways are the best characterized. Recently, evidence for the existence of a third major route, the twin-Arg pathway, was gathered. Proteins that use either one of these three different pathways possess special features that enable their specific interaction with the components of the targeting routes. Such targeting information is often contained in an N-terminal extension, the signal sequence, but can also be found within the mature domain of the targeted protein. Once the nascent chain starts to emerge from the ribosome, competition for the protein between different targeting factors begins. After recognition and binding, the targeting factor delivers the protein to the translocation sites at the cytoplasmic membrane. Only by means of a specific interaction between the targeting component and its receptor is the cargo released for further processing and translocation. This mechanism ensures the high-fidelity targeting of premembrane and membrane proteins to the translocation site.
Pseudomonas syringaePhytotoxins: Mode of Action, Regulation, and Biosynthesis by Peptide and Polyketide Synthetases
Authors: Bender Carol L. , Alarcón-Chaidez Francisco , Gross Dennis C. 
Published: December 2019

SUMMARYCoronatine, syringomycin, syringopeptin, tabtoxin, and phaseolotoxin are the most intensively studied phytotoxins of Pseudomonas syringae, and each contributes significantly to bacterial virulence in plants. Coronatine functions partly as a mimic of methyl jasmonate, a hormone synthesized by plants undergoing biological stress. Syringomycin and syringopeptin form pores in plasma membranes, a process that leads to electrolyte leakage. Tabtoxin and phaseolotoxin are strongly antimicrobial and function by inhibiting glutamine synthetase and ornithine carbamoyltransferase, respectively. Genetic analysis has revealed the mechanisms responsible for toxin biosynthesis. Coronatine biosynthesis requires the cooperation of polyketide and peptide synthetases for the assembly of the coronafacic and coronamic acid moieties, respectively. Tabtoxin is derived from the lysine biosynthetic pathway, whereas syringomycin, syringopeptin, and phaseolotoxin biosynthesis requires peptide synthetases. Activation of phytotoxin synthesis is controlled by diverse environmental factors including plant signal molecules and temperature. Genes involved in the regulation of phytotoxin synthesis have been located within the coronatine and syringomycin gene clusters; however, additional regulatory genes are required for the synthesis of these and other phytotoxins. Global regulatory genes such as gacS modulate phytotoxin production in certain pathovars, indicating the complexity of the regulatory circuits controlling phytotoxin synthesis. The coronatine and syringomycin gene clusters have been intensively characterized and show potential for constructing modified polyketides and peptides. Genetic reprogramming of peptide and polyketide synthetases has been successful, and portions of the coronatine and syringomycin gene clusters could be valuable resources in developing new antimicrobial agents.
Function and Regulation of Yeast Hexose Transporters
Authors: Özcan Sabire , Johnston Mark 
Published: December 2019

SUMMARY

Glucose, the most abundant monosaccharide in nature, is the principal carbon and energy source for nearly all cells. The first, and rate-limiting, step of glucose metabolism is its transport across the plasma membrane. In cells of many organisms glucose ensures its own efficient metabolism by serving as an environmental stimulus that regulates the quantity, types, and activity of glucose transporters, both at the transcriptional and posttranslational levels. This is most apparent in the baker’s yeast Saccharomyces cerevisiae, which has 20 genes encoding known or likely glucose transporters, each of which is known or likely to have a different affinity for glucose. The expression and function of most of these HXT genes is regulated by different levels of glucose. This review focuses on the mechanisms S. cerevisiae and a few other fungal species utilize for sensing the level of glucose and transmitting this information to the nucleus to alter HXT gene expression. One mechanism represses transcription of some HXT genes when glucose levels are high and works through the Mig1 transcriptional repressor, whose function is regulated by the Snf1-Snf4 protein kinase and Reg1-Glc7 protein phosphatase. Another pathway induces HXT expression in response to glucose and employs the Rgt1 transcriptional repressor, a ubiquitin ligase protein complex (SCF
Grr1
) that regulates Rgt1 function, and two glucose sensors in the membrane (Snf3 and Rgt2) that bind glucose and generate the intracellular signal to which Rgt1 responds. These two regulatory pathways collaborate with other, less well-understood, pathways to ensure that yeast cells express the glucose transporters best suited for the amount of glucose available.
Fungal Resistance to Plant Antibiotics as a Mechanism of Pathogenesis
Authors: Morrissey John P. , Osbourn Anne E. 
Published: December 2019

SUMMARY
Many plants produce low-molecular-weight compounds which inhibit the growth of phytopathogenic fungi in vitro. These compounds may be preformed inhibitors that are present constitutively in healthy plants (also known as phytoanticipins), or they may be synthesized in response to pathogen attack (phytoalexins). Successful pathogens must be able to circumvent or overcome these antifungal defenses, and this review focuses on the significance of fungal resistance to plant antibiotics as a mechanism of pathogenesis. There is increasing evidence that resistance of fungal pathogens to plant antibiotics can be important for pathogenicity, at least for some fungus-plant interactions. This evidence has emerged largely from studies of fungal degradative enzymes and also from experiments in which plants with altered levels of antifungal secondary metabolites were generated. Whereas the emphasis to date has been on degradative mechanisms of resistance of phytopathogenic fungi to antifungal secondary metabolites, in the future we are likely to see a rapid expansion in our knowledge of alternative mechanisms of resistance. These may include membrane efflux systems of the kind associated with multidrug resistance and innate resistance due to insensitivity of the target site. The manipulation of plant biosynthetic pathways to give altered antibiotic profiles will also be valuable in telling us more about the significance of antifungal secondary metabolites for plant defense and clearly has great potential for enhancing disease resistance for commercial purposes.
Pathology and Epizootiology of
Entomophaga maimaiga
Infections in Forest Lepidoptera
Authors: Hajek Ann E. 
Published: December 2019

SUMMARY
The insect-pathogenic fungal pathogen Entomophaga maimaiga is endemic to northeastern Asia and was first found in North America in 1989. Due to repeated epizootics and spread within populations of the major forest defoliator in northeastern North America, the gypsy moth (Lymantria dispar), this pathogen has gained much notoriety. Although this pathogen was purposely introduced to North America for biological control of L. dispar in 1910 to 1911, it is questionable whether it became established at the time of release and then remained at innocuous levels until relatively recently. Alternatively, the fungal strain present in North America today could be a more recent accidental introduction. DNA analysis demonstrates that this pathogen differs significantly from North American members of the same species complex (the Lepidoptera-specific Entomophaga aulicae species complex), and, to date, isolates of this introduced pathogen display little heterogeneity in North America. Nonsusceptible lepidopteran larvae have been identified, and either E. maimaiga is unable to penetrate the cuticle or the fungus cannot survive within the hemocoel. In the latter case, although E. maimaiga grows as protoplasts lacking cell walls in the host hemolymph, glycoproteins on plasma membranes of the protoplasts could lead to host recognition. Epizootiological studies demonstrate a clear association between fungal activity and environmental moisture but little association with host density under hypothesized conditions of high fungal density. Prediction of the occurrence of epizootics is not yet possible. E. maimaiga is easily established in new areas by releasing azygospores, but the ability to use this pathogen further for biological control will depend, in large part, on the development of mass production systems.
More than 80% of total knee replacements can last for 25 years
Authors: Cook Rob , Davidson Peter , Martin Rosie 
Published: December 2019

The studyEvans JT, Walker R, Evans W, Blom AW, Sayers A, Whitehouse MRHow long does a knee replacement last? A systematic review and meta-analysis of case series and national registry reports with more than 15 years of follow-up.Published on 16 February 2019 Lancet 2019;393:655-63This study was supported by the NIHR Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol.To read the full NIHR Signal, go to: https://discover.dc.nihr.ac.uk/content/signal-000776/more-than-80-of-total-knee-replacements-can-last-for-25-years
Decreased amplitude and reliability of odor-evoked responses in two mouse models of autism
Authors: Geramita Matthew A. , Wen Jing A. , Rannals Matthew D. , Urban Nathan N. 
Published: December 2019

Sensory processing deficits are increasingly recognized as core symptoms of autism spectrum disorders (ASDs). However the molecular and circuit mechanisms that lead to sensory deficits are unknown. We show that two molecularly disparate mouse models of autism display similar deficits in sensory-evoked responses in the mouse olfactory system. We find that both Cntnap2- and Shank3-deficient mice of both sexes exhibit reduced response amplitude and trial-to-trial reliability during repeated odor presentation. Mechanistically, we show that both mouse models have weaker and fewer synapses between olfactory sensory nerve (OSN) terminals and olfactory bulb tufted cells and weaker synapses between OSN terminals and inhibitory periglomerular cells. Consequently, deficits in sensory processing provide an excellent candidate phenotype for analysis in ASDs. NEW & NOTEWORTHY The genetics of autism spectrum disorder (ASD) are complex. How the many risk genes generate the similar sets of symptoms that define the disorder is unknown. In particular, little is understood about the functional consequences of these genetic alterations. Sensory processing deficits are important aspects of the ASD diagnosis and may be due to unreliable neural circuits. We show that two mouse models of autism, Cntnap2- and Shank3-deficient mice, display reduced odor-evoked response amplitudes and reliability. These data suggest that altered sensory-evoked responses may constitute a circuit phenotype in ASDs.
Oxytocin increases inhibitory synaptic transmission and blocks development of long-term potentiation in the lateral amygdala
Authors: Crane J. W. , Holmes N. M. , Fam J. , Westbrook R. F. , Delaney A. J. 
Published: December 2019

Oxytocin (OT) is a neuroactive peptide that influences the processing of fearful stimuli in the amygdala. In the central nucleus of the amygdala, the activation of OT receptors alters neural activity and ultimately suppresses the behavioral response to a fear conditioned stimulus. Receptors for OT are also found in the lateral amygdala (LA), and infusion of OT into the basolateral amygdala complex affects the formation and consolidation of fear memories. Yet, how OT receptor activation alters neurons and neural networks in the LA is unknown. In this study we used whole cell electrophysiological recordings to determine how OT-receptor activation changes synaptic transmission and synaptic plasticity in the LA of Sprague-Dawley rats. Our results demonstrate that OT-receptor activation results in a 200% increase in spontaneous inhibitory transmission in the LA that leads to the activation of presynaptic GABAB receptors. The activation of these receptors inhibits excitatory transmission in the LA, blocking long-term potentiation of cortical inputs onto LA neurons. Hence, this study provides the first demonstration that OT influences synaptic transmission and plasticity in the LA, revealing a mechanism that could explain how OT regulates the formation and consolidation of conditioned fear memories in the amygdala. NEW & NOTEWORTHY This study investigates modulation of synaptic transmission by oxytocin (OT) in the lateral amygdala (LA). We demonstrate that OT induces transient increases in spontaneous GABAergic transmission by activating interneurons in the basolateral amygdala. The resultant increase in GABA release in the LA activates presynaptic GABAB receptors on both inhibitory and excitatory inputs onto LA neurons, reducing release probability at these synapses. We subsequently demonstrate that OT modulates synaptic plasticity at cortical inputs to the LA.
Iconografia musical na obra de Henri Rousseau
Authors: Lima Andrei Fernando Ferreira 
Published: December 2019

Número significativo de artistas, teóricos da música e historiadores da arte exploraram a diversidade e complexidade dos nexos entre pintura e música ao longo dos séculos. No domínio das artes visuais, as referências à música são abundantes, ganhando expressão tanto pelos temas iconográficos quanto pela reflexão sobre os fundamentos da linguagem musical (ritmo, harmonia, cromatismo). A partir das analogias e interferências entre as duas formas de expressão, propomos uma leitura crítica desse fenômeno na obra de Henri Rousseau, artista francês que desenvolveu uma iconografia particular inspirada no assunto, através da qual explora as possibilidades de representação pictórica da música, tendo em vista efeitos de sentido integrados às suas narrativas visuais.
Multimodel Subseasonal Forecasts of Spring Cold Spells: Potential Value for the Hazelnut Agribusiness
Authors: Materia Stefano , Muñoz Ángel G. , Álvarez-Castro M. Carmen , Mason Simon J. , Vitart Frederic , Gualdi Silvio 
Published: December 2019

AbstractProducing probabilistic subseasonal forecasts of extreme events up to six weeks in advance is crucial for many economic sectors. In agribusiness, this time scale is particularly critical because it allows for mitigation strategies to be adopted for counteracting weather hazards and taking advantage of opportunities. For example, spring frosts are detrimental for many nut trees, resulting in dramatic losses at harvest time. To explore subseasonal forecast quality in boreal spring, identified as one of the most sensitive times of the year by agribusiness end users, we build a multisystem ensemble using four models involved in the Subseasonal to Seasonal Prediction project (S2S). Two-meter temperature forecasts are used to analyze cold spell predictions in the coastal Black Sea region, an area that is a global leader in the production of hazelnuts. When analyzed at the global scale, the multisystem ensemble probabilistic forecasts for near-surface temperature are better than climatological values for several regions, especially the tropics, even many weeks in advance; however, in the coastal Black Sea, skill is low after the second forecast week. When cold spells are predicted instead of near-surface temperatures, skill improves for the region, and the forecasts prove to contain potentially useful information to stakeholders willing to put mitigation plans into effect. Using a cost–loss model approach for the first time in this context, we show that there is added value of having such a forecast system instead of a business-as-usual strategy, not only for predictions released 1–2 weeks ahead of the extreme event, but also at longer lead times.
The Association of Serum Eosinophilia with Structured Histopathology in Chronic Rhinosinusitis
Authors: Ganti Ashwin , Kuhar Hannah N. , Eggerstedt Michael , Mahdavinia Mahboobeh , Gattuso Paolo , Batra Pete S. , Tajudeen Bobby A. 
Published: December 2019

Background: Prior studies have demonstrated associations between serum eosinophilia and chronic rhinosinusitis (CRS) pathogenesis. However, the association of serum eosinophilia with histopathology profiling in CRS has not been fully delineated and may help better characterize CRS disease burden prior to surgery. Methods: A structured histopathology report of 13 variables was utilized to analyze sinus tissue removed during functional endoscopic sinus surgery (FESS). Complete blood count (CBC) with differential was drawn within 4 weeks prior to FESS. Serum eosinophilia was defined as >6.0% (>0.60 th/μL). Histopathology variables were compared among patients. Results: A total of 177 CRS patients (37 with serum eosinophilia and 140 with normal serum eosinophilia) were analyzed. Compared to CRS patients with normal serum eosinophil counts, CRS patients with serum eosinophilia demonstrated increased polypoid disease (67.6% vs 35.0%, P < .001), eosinophil aggregates (45.9% vs 20.7%, P = .003), and eosinophils per high-power field (>5/HPF) (67.6% vs 40.7%, P = .003). Conclusion: CRS patients with serum eosinophilia demonstrated severe disease burden on histopathology with high levels of polypoid disease and tissue eosinophilia. However, a considerable number of patients without serum eosinophilia demonstrated eosinophilic disease on histopathology, indicating that preoperative serum eosinophilia alone could not be reliably used to predict eosinophilic CRS. Level of evidence: 4
Post-treatment curcumin reduced ischemia–reperfusion-induced pulmonary injury via the Notch2/Hes-1 pathway
Authors: bo HaiZou , feng XiaoSun 
Published: December 2019

Objective To investigate the influence of curcumin on the Notch2/Hes-1 pathway after pulmonary injury induction via limb ischemia–reperfusion (I/R). Methods Adult male Sprague–Dawley rats were randomly divided into four groups (n = 30 each): sham, I/R, curcumin post-treatment (I/R+Cur), and inhibitor (I/R+DAPT). Hind-limb ischemia was induced for 4 hours, followed by reperfusion for 4 hours. After ischemia, curcumin (200 mg/kg) or DAPT (0.5 µm) was injected intraperitoneally in the I/R+Cur or I/R+DAPT group, respectively. PaO2 was examined after 4 hours of reperfusion. Pathological changes in the lung and the apoptotic index (AI) were examined. Lung malondialdehyde (MDA), tumor necrosis factor (TNF)-α, and interleukin (IL)-1β levels, the wet/dry (W/D) ratio, semi-quantitative score of lung injury (SSLI), and Notch2 protein and Hes-1 mRNA expression were also examined. Results In the I/R group, inflammatory changes were observed, AI increased, and MDA, SSLI, W/D, TNF-α, IL-1β, Notch2, and Hes1-mRNA expression increased, while PaO2 decreased compared with the Sham group. Pathological changes in the I/R+Cur group were reversed. All indexes in the I/R+DAPT and I/R+Cur group were similar. Conclusion Curcumin post-treatment reduced I/R-induced lung injury in rats. Its mechanism may be related to the inhibition of Notch2/Hes-1 signaling pathway and the release of inflammatory factors.