bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of the functional role of the maizeGlossy2 and Glossy2-likegenes in cuticular lipid deposition
Authors: Alexander Liza Esther , Okazaki Yozo , Schelling Michael A. , Davis Aeriel , Zheng Xiaobin , Rizhsky Ludmila , Yandeau-Nelson Marna D. , Saito Kazuki , Nikolau Basil J. 
Published: February 2020

ABSTRACTPlant epidermal cells express unique molecular machinery that juxtapose the assembly of intracellular lipid components and the unique extracellular cuticular lipids that are unidirectionally secreted to plant surfaces. In maize (Zea maysL.), mutations at theglossy2 (gl2)locus affect the deposition of extracellular cuticular lipids. Sequence-based genome scanning identified a novelgl2homolog in the maize genome,Gl2-like. Sequence homology identifies that both theGl2-likeandGl2genes are members of the BAHD superfamily of acyltransferases, with close sequence homology to the ArabidopsisCER2gene. Transgenic experiments demonstrate thatGl2-likeandGl2functionally complement the Arabidopsiscer2mutation, with differential impacts on the cuticular lipids and the lipidome of the plant, particularly affecting the longer alkyl chain acyl lipids, particularly at the 32-carbon chain length. Site-directed mutagenesis of the putative BAHD catalytic HXXXDX-motif indicates thatGl2-likerequires this catalytic capability to fully complement thecer2function, butGl2can accomplish this without the need for this catalytic motif. These findings demonstrate that bothGl2andGl2-likeoverlap in their cuticular lipid function, however the two genes have evolutionary diverged to acquire non-overlapping functions.One-sentence summaryTransgenesis dissection of the functional roles of the maizeGlossy2andGlossy2-Likegenes in cuticular lipid deposition.
Spiking attractor model of motor cortex explains modulation of neural and behavioral variability by prior target information
Authors: Rostami Vahid , Rost Thomas , Schmitt Felix J. , van Albada Sacha J. , Riehle Alexa , Nawrot Martin P. 
Published: February 2020

AbstractWhen preparing a movement, we often rely on partial or incomplete information, which can decrement task performance. In behaving monkeys we show that the degree of cued target information is reflected in both, neural variability in motor cortex and behavioral reaction times. We study the underlying mechanisms in a spiking motor-cortical attractor model. By introducing a novel and biologically realistic network topology where excitatory neuron clusters are locally balanced with inhibitory neuron clusters we robustly achieve metastable network activity across a wide range of network parameters. In application to the monkey task, the model performs target-specific action selection and accurately reproduces the task-epoch dependent reduction of trial-to-trial variabilityin vivowhere the degree of reduction directly reflects the amount of processed target information, while spiking irregularity remained constant throughout the task. In the context of incomplete cue information, the increased target selection time of the model can explain increased behavioral reaction times . We conclude that context-dependent neural and behavioral variability is a signum of attractor computation in the motor cortex.
Nanobody-dependent delocalization of endocytic machinery in Arabidopsis root cells dampens their internalization capacity
Authors: Winkler Joanna , De Meyer Andreas , Mylle Evelien , Grones Peter , Storme Veronique , Van Damme Daniël 
Published: February 2020

AbstractPlant cells perceive and adapt to an ever-changing environment by modifying their plasma membrane (PM) proteome. Whereas secretion deposits new integral membrane proteins, internalization by endocytosis removes membrane proteins and associated ligands, largely with the aid of adaptor protein complexes and the scaffolding molecule clathrin. Two adaptor protein complexes function in clathrin-mediated endocytosis at the PM in plant cells, the heterotetrameric Adaptor Protein 2 (AP-2) complex and the octameric TPLATE complex (TPC). Whereas single subunit mutants in AP-2 develop into viable plants, genetic mutation of a single TPC subunit causes fully penetrant male sterility and silencing single subunits leads to seedling lethality. To address TPC function in somatic root cells, while minimizing indirect effects on plant growth, we employed nanobody-dependent delocalization of a functional, GFP-tagged TPC subunit, TML, in its respective homozygous genetic mutant background. In order to decrease the amount of functional TPC at the PM, we targeted our nanobody construct to the mitochondria and fused it to TagBFP2 to visualize it independently of its bait. We furthermore limited the effect of our delocalization to those tissues that are easily accessible for live-cell imaging by expressing it from the PIN2 promotor, which is active in root epidermal and cortex cells. With this approach, we successfully delocalized TML from the PM. Moreover, we also show co-recruitment of TML-GFP and AP2A1-TagRFP to the mitochondria, suggesting that our approach delocalized complexes, rather than individual adaptor complex subunits. In line with the specific expression domain, we only observed minor effects on root growth, yet realized a clear reduction of endocytic flux in epidermal root cells. Nanobody-dependent delocalization in plants, here exemplified using a TPC subunit, has the potential to be widely applicable to achieve specific loss-of-function analysis of otherwise lethal mutants.
Deep-sea corals near cold seeps associate with chemoautotrophic bacteria that are related to the symbionts of cold seep and hydrothermal vent mussels
Authors: Vohsen Samuel A. , Gruber-Vodicka Harald R. , Osman Eslam O. , Saxton Matthew A. , Joye Samantha B. , Dubilier Nicole , Fisher Charles R. , Baums Iliana B. 
Published: February 2020

AbstractCnidarians are known for their symbiotic relationships, yet no known association exists between corals and chemoautotrophic microbes. Deep-sea corals, which support diverse animal communities in the Gulf of Mexico, are often found on authigenic carbonate in association with cold seeps. Sulfur-oxidizing chemoautotrophic bacteria of the SUP05 cluster are dominant symbionts of bathymodiolin mussels at cold seeps and hydrothermal vents around the world and have also been found in association with sponges. Therefore, we investigated whether other basal metazoans, corals, also associate with bacteria of the SUP05 cluster and report here that such associations are widespread. This was unexpected because it has been proposed that cnidarians would not form symbioses with chemoautotrophic bacteria due to their high oxygen demand and their lack of specialized respiratory structures. We screened corals, water, and sediment for SUP05 using 16S metabarcoding and found SUP05 phylotypes associated with corals at high relative abundance (10 – 91%). These coral-associated SUP05 phylotypes were coral host specific, absent in water samples, and rare or not detected in sediment samples. The genome of one SUP05 phylotype associated withParamuriceasp. type B3, contained the genetic potential to oxidize reduced sulfur compounds and fix carbon and these pathways were transcriptionally active. Finally, the relative abundance of this SUP05 phylotype was positively correlated with chemoautotrophically-derived carbon and nitrogen input into the coral holobiont based on stable carbon and nitrogen isotopic compositions. We propose that SUP05 may supplement the diet of its host coral through chemoautotrophy or may provide nitrogen, essential amino acids, or vitamins. This is the first documented association between a chemoautotrophic symbiont and a cnidarian, broadening the known symbioses of corals and may represent a novel interaction between coral communities and cold seeps.
Exploring a natural baseline for large herbivore biomass
Authors: Fløjgaard Camilla , Pedersen Pil Birkefeldt , Sandom Christopher J. , Svenning Jens-Christian , Ejrnæs Rasmus 
Published: February 2020

AbstractThe massive global losses of large mammals in the Pleistocene have triggered severe ecosystem changes including changed nutrient cycles, fire regimes and climate, shifts in biomes and loss of biodiversity. Large herbivores create and diversify resources and living space for other organisms and thereby play an important role in ecosystem functioning and biodiversity conservation. However, even today large herbivores are regulated, hunted and driven to extinction to a degree where intact large-herbivore communities are largely non-existent. Consequently, natural density and biomass of large-herbivores for restoration of ecosystems are poorly known. To address this knowledge gap, we apply the scaling pattern for consumer-producer relationships and show that the biomass of large herbivores in ecosystems across the world is considerably lower than expected from primary productivity. African ecosystems have the strongest consumer-producer relationship and assuming that African ecosystems approach a natural baseline, we use this relationship to predict large herbivore biomass in Europe as an example. Our findings indicate that restoring large herbivore biomass would entail increasing large herbivore biomass by orders of magnitude in most ecosystems, which potentially changes the perspective on large herbivores in conservation and restoration projects.
S1PR1 regulates the quiescence of lymphatic vessels by inhibiting laminar shear stress-dependent VEGF-C signaling
Authors: Geng Xin , Yanagida Keisuke , Akwii Racheal G. , Choi Dongwon , Chen Lijuan , Ho YenChun , Cha Boksik , Mahamud Md. Riaj , de Ruiz Karen Berman , Ichise Hirotake , Chen Hong , Wythe Joshua , Mikelis Constantinos M. , Hla Timothy , Srinivasan R. Sathish 
Published: February 2020

AbstractDuring the growth of lymphatic vessels (lymphangiogenesis), lymphatic endothelial cells (LECs) at the growing front sprout by forming filopodia. Those tip cells are not exposed to circulating lymph, as they are not lumenized. In contrast, LECs that trail the growing front are exposed to shear stress, become quiescent and remodel into stable vessels. The mechanisms that coordinate the opposed activities of lymphatic sprouting and maturation remain poorly understood. Here we show that the canonical tip cell marker Delta-Like 4 (DLL4) promotes sprouting lymphangiogenesis by enhancing Vascular Endothelial Growth Factor C (VEGF-C) /VEGF Receptor 3 (VEGFR3) signaling. However, in lumenized lymphatic vessels laminar shear stress (LSS) inhibits the expression of DLL4, as well as additional tip cell markers. Paradoxically, LSS also upregulates VEGF-C/VEGFR3 signaling in LECs, but sphingosine 1-phosphate (S1P) receptor 1 (S1PR1) activity antagonizes LSS-mediated VEGF-C signaling to promote lymphatic vascular quiescence. Correspondingly,S1pr1loss in LECs induced lymphatic vascular hypersprouting and hyperbranching, which could be rescued by reducingVegfr3gene dosagein vivo. In addition, S1PR1 regulates lymphatic vessel maturation by promoting membrane localization of the tight junction molecule Claudin-5. Our findings suggest a new paradigm in which LSS induces quiescence and promotes the survival of LECs by downregulating DLL4 and enhancing VEGF-C signaling, respectively. S1PR1 dampens LSS/VEGF-C signaling, thereby preventing sprouting from quiescent lymphatic vessels. These results also highlight the distinct roles that S1PR1 and DLL4 play in LECs when compared to their known roles in the blood vasculature.
Mapping Spatially Distributed Material Properties in Finite Element Models of Plant Tissue Using Computed Tomography
Authors: Stubbs Christopher J , Larson Ryan , Cook Douglas D 
Published: February 2020

AbstractPlant tissues are often heterogeneous. To accurately investigate these tissues, we will need methods to spatially map these tissue stiffness values onto finite element models. The purpose of this research is to develop a method for using specimen-specific computed tomography data to inform the spatial mapping of Young’s modulus values on finite element models. The spatial mapping of Young’s modulus was calculated and then used to predict the response of specimen tests. Results indicated that this method can be used to obtain spatial distributions of material properties, thus enabling finite element models that account for material heterogeneity.
Learning prediction error neurons in a canonical interneuron circuit
Authors: Hertäg Loreen , Sprekeler Henning 
Published: February 2020

AbstractSensory systems constantly compare external sensory information with internally generated predictions. While neural hallmarks of prediction errors have been found throughout the brain, the circuit-level mechanisms that underlie their computation are still largely unknown. Here, we show that a well-orchestrated interplay of three interneuron types shapes the development and refinement of negative prediction-error neurons in a computational model of mouse primary visual cortex. By balancing excitation and inhibition in multiple pathways, experience-dependent inhibitory plasticity can generate different variants of prediction-error circuits, which can be distinguished by simulated optogenetic experiments. The experience-dependence of the model circuit is consistent with that of negative prediction-error circuits in layer 2/3 of mouse primary visual cortex. Our model makes a range of testable predictions that may shed light on the circuitry underlying the neural computation of prediction errors.
Differential glycosylation of alpha-1-acid glycoprotein (AGP-1) contributes to its functional diversity
Authors: Sumanth Mosale Seetharam , Jacob Shancy P , Abhilasha Kandahalli Venkataranganayaka , Manne Bhanu Kanth , Basrur Venkatesha , Lehoux Sylvain , Campbell Robert A , Yost Christian C , Rhondina Matthew T , McIntyre Thomas M , Cummings Richard D , Weyrich Andrew S , Marathe Gopal K 
Published: February 2020

AbstractAlpha-1-acid glycoprotein (AGP-1) is a positive acute phase glycoprotein with uncertain functions. Serum AGP-1 (sAGP-1) is primarily derived from hepatocytes and circulates as 12 to 20 different glycoforms. We isolated a glycoform secreted from stimulated human neutrophils (nAGP-1). Its peptide sequence was identical to hepatocyte-derived sAGP-1, but nAGP-1 differed from sAGP-1 in its chromatographic behaviour, electrophoretic mobility, and glycosylation. The function of these two glycoforms also differed. sAGP-1 activated neutrophil adhesion, migration and NETosis in a dose-dependent fashion, while nAGP-1 was ineffective as an agonist for these events. Furthermore, sAGP-1, but not nAGP-1, inhibited LPS-stimulated NETosis. However, nAGP-1 inhibited sAGP-1-stimulated neutrophil NETosis. The discordant effect of the differentially glycosylated AGP-1 glycoforms was also observed in platelets where neither of the AGP-1 glycoforms alone stimulated aggregation of washed human platelets, but sAGP-1, and not nAGP-1, inhibited aggregation induced by Platelet-activating Factor (PAF) or ADP, but not by thrombin. These functional effects of sAGP-1 correlated with intracellular cAMP accumulation and were accompanied by phosphorylation of the PKA substrate Vasodialator stimulated phosphoprotein (VASP) and reduction of Akt, ERK, and p38 phosphorylation. Thus, the sAGP-1 glycoform limits platelet reactivity while nAGP-1 glycoform also limits pro-inflammatory actions of sAGP-1. These studies identify new functions for this acute phase glycoprotein and demonstrate that the glycosylation of AGP-1 controls its effects on two critical cells of acute inflammation.
Bacterial Community Composition and Diversity along the Southern Coastlines of the Atlantic Ocean in Cape Town, South Africa
Authors: Olapade Ola A. 
Published: February 2020

AbstractThe spatial distribution and diversity within bacterioplankton assemblages in four coastal sites along the southern points of the Atlantic Ocean were examined using the Illumina high-throughput that targets 16S rRNA genes to examine indigenous bacterial assemblages in the littoral zones along the coast of the ocean. Results of the study showed very similar bacterial representation between the coastal sites with majority of the sequences affiliated with Proteobacteria (52 to 59%), Bacteriodetes (21 to 31%) followed by Actinobacteria (3 to 9.5%) and Planctomycetes (2.1 to 4.5%). The bacterioplankton assemblages at each site examined were quite diverse, with members of the Gammaproteobacteria found as the most abundant bacterial class among the four sites. However, clear differences were observed among the sites at the order level, with the Chromatiales the more dominant in the closer CPTI sites, while clades belonging to the Flavobacteriales and Rhodobacterales were more prevalent in the two CPTA sites. While the results of UPGMA clustering and principle coordinate (PCoA) revealed two spatially separate clusters among sites, canonical correspondence (CCA) analysis indicated that environmental variables such as temperature, pH and conductivity were probably the major influencers of bacterial occurrences at the coastal sites.
Social networks feed the food supplements shadow market
Authors: Sfodera Fabiola , Mattiacci Alberto , Nosi Costanza , Mingo Isabella 
Published: March 2020

PurposeThe paper investigates the role of social networks in the millennials’ decision-making process of illegal and unnotified food supplements purchase. The connections and interactions that (co) produce information are studied with a holistic perspective of social sustainability as a development driver of business model innovation.Design/methodology/approachAn exploratory qualitative multiple analysis study was conducted in two consecutive phases. Data from 23 semi-structured individual interviews were collected, followed by a netnographic analysis of the Facebook virtual community.FindingsThe results show that the decision-making process does not develop following the traditional sequence, as social networks modify the wellness meaning creation process and reduce risk perception. Moreover, social networks introduce the use of similar experiences of others and online information and emotional support on unethical and unhealthy behavior.Research limitations/implicationsDue to the application to a social network, the results should be understood within this context. Future studies would benefit by expanding the target and the range of social networks explored.Practical implicationsThe official information quality control, as a prerogative of public and professional health stakeholders, and the medialization of medicalization, contribute to the conscious development of their wellness meanings and values.Originality/valueThis work represents one of the first attempts to investigate resources integration through social networks in the pre-purchase decision-making process of unnotified and illegal food supplements. Unethical and unhealthy behavior develops through the interaction of actors, firms, influencers and individuals over social networks.
Reliability modeling of multi-version software system incorporating the impact of infected patching
Authors: Anand Adarsh , Kaur Jasmine , Inoue Shinji 
Published: February 2020

PurposeThe purpose of the present work is to mathematically model the reliability growth of a multi-version software system that is affected by infected patches.Design/methodology/approachThe work presents a mathematical model that studies the reliability change due to the insertion of an infected patch in multi-version software. Various distribution functions have been considered to highlight the varied aspects of the model. Furthermore, weighted criteria approach has been discussed to facilitate the choice of the model.FindingsThe model presented here is able to quantify the effect of an infected patch on multi-version software. The model captures the hike in bug content due to an infected patch.Originality/valueMulti-version systems have been studied widely, but the role of an infected patch has not been yet explored. The effect of an infected patch has been quantified by modeling the extra bugs generated in the system. This bug count would prove helpful in further studies for optimal resource allocation and testing effort allocation.
Measuring online live streaming of perceived servicescape
Authors: Chen Yu-Hsin , Chen Min-Cing , Keng Ching-Jui 
Published: February 2020

PurposeThis study aimed to develop and validate an online live streaming perceived servicescape (OLSPS) scale that can help platform service providers to develop strategies for new live streaming channel promotions.Design/methodology/approachThis study conceptualized the construct of OLSPS and the four-phase procedure of the 66-item OLSPS scale development, including item generation, item purification, scale validation, measure application and testing of hypotheses. It also provided a research framework to assess audiences' cognition and behavioral intention, and an online survey on 420 live streaming users (social platforms, n = 210; native platforms, n = 210) was conducted.FindingsThis study developed and validated a 35-item OLSPS scale with eight dimensions. The results of the empirical model showed that OLSPS is positively correlated with the audiences' cognition and behavioral intention. Furthermore, parasocial interaction experience showed a positive moderation on channel trust.Originality/valueThis study is a pioneering effort to develop and validate an OLSPS scale. The results could be helpful for researchers in building OLSPS and for managers in assessing and promoting users' acceptance of online live streaming platforms.
Mycoheterotrophic plants living on arbuscular mycorrhizal fungi are generally enriched in 13C, 15N and 2H isotopes
Authors: Gomes Sofia I. F. , Merckx Vincent S. F. T. , Kehl Judith , Gebauer Gerhard 
Published: February 2020

Abstract

Fully mycoheterotrophic plants are thought to obtain carbon exclusively from their root‐associated fungal partners. The general enrichment of these plants in the heavy isotopes 13C and 15N suggests that fungi are the main nutrient source for these plants. Yet, the majority of studies have targeted mycoheterotrophic plants associated with ectomycorrhizal, orchid mycorrhizal and saprotrophic fungi, while mycoheterotrophic plants living on arbuscular mycorrhizal fungi remain understudied.

Here, we sampled 13 species of arbuscular mycorrhizal fully mycoheterotrophic plants from five families and co‐occurring autotrophic reference plants growing in forests of tropical South America, tropical South East Asia and temperate Australasia. We measured stable isotope natural abundances (δ13C, δ15N, δ2H and δ18O), determined total nitrogen concentrations and used high‐throughput DNA sequencing to characterize the arbuscular mycorrhizal fungal communities associated with the sampled mycoheterotrophic plants.

We observed a general enrichment in 13C and 15N isotopes across mycoheterotrophic plant families and geographic regions. We confirm cases where no 15N enrichment is present, but we show that in general arbuscular mycoheterotrophic plants are enriched in 15N. Moreover, we demonstrate for the first time that these plants are significantly enriched in 2H but not in 18O in relation to their autotrophic references. The fungal communities targeted by the mycoheterotrophs mainly consist of Glomeraceae and show strong association with the isotopic signatures and geographic origin of the plants.

Synthesis. Our findings enlarge the limited knowledge on the multi‐element stable isotopic signatures of mycoheterotrophic plants living on arbuscular mycorrhizal fungi. We show that these plants are enriched in 13C and 2H as expected due to their mycoheterotrophic nutrition, and that in general they are also enriched in 15N, despite some exceptions. Variation in stable isotope signatures is likely influenced by plant taxonomy, geography and fungal community composition.