bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigating age- and sex-specific effects of socialization on voluntary ethanol administration using a novel vapor paradigm
Authors: Walker Christopher D. , Sexton Hannah G. , Risher Mary-Louise 
Published: November 2020

ABSTRACTIntroductionAdolescence is characterized as a transitional developmental period between childhood and adulthood that is associated with increased freedom and novel experiences that are frequently peer-influenced. Due to newfound independence, there is a higher prevalence of alcohol consumption, which is heightened by the rewarding effects of alcohol. However, the contributions of social interaction and sexual dimorphism to alcohol intake are not fully understood. Here we explore the use a novel self-administration ethanol (EtOH) vapor system to investigate the sexual dimorphic nature of socially facilitated ethanol exposure.MethodsAdolescent and adult male and female Sprague-Dawley rats underwent a novel voluntary intermittent EtOH vapor paradigm. Nosepoke initiated self-administration vapor chambers administered 20mg/L of vaporized EtOH or air into the chamber following each nosepoke. Beginning on postnatal day 30 (PND30), during the onset of adolescence, or 70 (PND70), at the onset of adulthood, animals were placed in vapor chambers for 4hr every other day for 40 sessions. All animals underwent 10 sessions with their cagemate (social access) followed by 10 sessions in isolation (isolated access), a 10-day forced abstinence period, 10 sessions isolated access, and 10 sessions social access.ResultsThese data reveal that despite low EtOH consumption across all groups, adolescent (PND30) and adult (PND70) female rats voluntarily self-administered more EtOH vapor per body weight than age-matched males, while male rats increased EtOH preference over sessions regardless of age. In addition, all rats regardless of sex or age voluntarily self-administered more EtOH vapor per body weight during the social access session than during the subsequent isolated access sessions.ConclusionThese data demonstrate that under these experimental parameters, male and female rats regardless of age do not self-administer high quantities of EtOH vapor using this paradigm. Further work is required to determine whether the nose-poke EtOH vapor self-administration apparatus can be modified to promote high voluntary EtOH consumption that can be socially facilitated. These data demonstrate that with further investigation, the self-administration EtOH vapor system could be an effective alternative to other methods of voluntary EtOH administration to further our understanding of socially facilitated drinking.
The zinc finger protein CLAMP promotes long-range chromatin interactions that mediate dosage compensation of theDrosophilamale X-chromosome
Authors: Jordan William , Larschan Erica 
Published: November 2020

SummaryDrosophiladosage compensation is an important model system for defining how active chromatin domains are formed. The Male-specific lethal dosage compensation complex (MSLc) increases transcript levels of genes along the length of the single male X-chromosome to equalize with that on the two female X-chromosomes. The strongest binding sites for MSLc cluster together in three-dimensional space independent of MSLc because clustering occurs in both sexes. CLAMP, a non-sex specific, ubiquitous zinc finger protein, binds synergistically with MSLc to enrich the occupancy of both factors on the male X-chromosome. Here, we demonstrate that CLAMP promotes the observed clustering of MSLc bindings sites. Genome-wide, CLAMP promotes interactions between active chromatin regions. Moreover, the X-enriched CLAMP protein more strongly promotes longer-range interactions on the X-chromosome than autosomes. Genome-wide, CLAMP promotes interactions between active chromatin regions together with other insulator proteins. Overall, we define how long-range interactions which are modulated by a locally enriched ubiquitous transcription factor promote hyper-activation of the X-chromosome to mediate dosage compensation.
Bacterially produced small molecules stimulate diatom growth
Authors: Sittmann John , Bae Munhyung , Mevers Emily , Li Muzi , Quinn Andrew , Sriram Ganesh , Clardy Jon , Liu Zhongchi 
Published: November 2020

AbstractDiatoms are photosynthetic microalgae that fix a significant fraction of the world’s carbon. Because of their photosynthetic efficiency and high-lipid content, diatoms are priority candidates for biofuel production. Here, we report that sporulatingBacillus thuringiensiswhen in co-culture with a marine diatomPhaeodactylum tricornutumsignificantly increases the diatom cell count. Bioassay-guided purification led to the identification of two diketopiperazines (DKPs) that both stimulateP. tricornutumgrowth and increase its lipid content. RNA-seq analysis revealed upregulation of a small set ofP. tricornutumgenes involved in iron starvation response and nutrient recycling when DKP was added to the diatom culture. This work demonstrates that two DKPs produced by a bacterium could positively impactP. tricornutumgrowth and lipid content, offering new approaches to enhanceP. tricornutum-based biofuel production. As increasing numbers of DKPs are isolated from marine microbes, the work gives potential clues to bacterially produced growth factors for marine microalgae.One sentence summaryTwo diketopiperazines (DKPs) produced by sporulating bacteriumBacillus thuringiensisstimulate diatomP. tricornutumgrowth and increase diatom lipid content.
Shared genetic architecture underlying root metaxylem phenotypes under drought stress in cereals
Authors: Klein Stephanie P. , Reeger Jenna E. , Kaeppler Shawn M. , Brown Kathleen M. , Lynch Jonathan P. 
Published: November 2020

AbstractRoot metaxylem are phenotypically diverse structures whose function is related to their anatomy, particularly under drought stress. Much research has dissected the genetic machinery underlying metaxylem phenotypes in dicots, but monocots are relatively unexplored. In maize (Zea mays), a robust pipeline integrated a GWAS of root metaxylem phenes under well-watered and water stress conditions with a gene co-expression network to identify candidate genes most likely to impact metaxylem phenotypes. We identified several promising candidate genes in 14 gene co-expression modules inferred to be functionally relevant to xylem development. We also identified five gene candidates that co-localized in multiple root metaxylem phenes in both well-watered and water stress conditions. Using a rice GWAS conducted in parallel, we detected overlapping genetic architecture influencing root metaxylem phenotypes by identifying eight pairs of syntenic candidate genes significantly associated with metaxylem phenes. There is evidence that the genes of these syntenic pairs may be involved in biosynthetic processes related to the cell wall, hormone signaling, oxidative stress responses, and drought responses. Our study demonstrates a powerful new strategy for identifying promising gene candidates and suggests several gene candidates that may enhance our understanding of vascular development and responses to drought in cereals.One sentence summaryCross-species genome-wide association studies and a gene coexpression network identified genes associated with root metaxylem phenotypes in maize under water stress and non-stress and rice.
Mosquitoes of the Maculipennis complex in Northern Italy
Authors: Calzolari Mattia , Desiato Rosanna , Albieri Alessandro , Bellavia Veronica , Bertola Michela , Bonilauri Paolo , Callegari Emanuele , Canziani Sabrina , Lelli Davide , Mosca Andrea , Mulatti Paolo , Peletto Simone , Ravagnan Silvia , Roberto Paolo , Torri Deborah , Pombi Marco , Di Luca Marco , Montarsi Fabrizio 
Published: November 2020

AbstractThe correct identification of mosquito vectors is often hampered by the presence of morphologically indiscernible sibling species. The Maculipennis complex is one of these groups which include both malaria vectors of primary importance and species of low/negligible epidemiological relevance, of which distribution data in Italy are outdated. Our study was aimed at providing an updated distribution of Maculipennis complex in Northern Italy through the sampling and morphological/molecular identification of specimens from five regions. The most abundant species wasAnopheles messeae s.l.(2032), followed byAnopheles maculipennis s.s.(418),Anopheles atroparvus(28) andAnopheles melanoon(13). The distribution of species was characterized by Ecological Niche Models (ENMs), fed by recorded points of presence. ENMs provided clues on the ecological preferences of the detected species, withAn. messeae s.l.linked to stable breeding sites andAn. maculipennis s.s.more associated to ephemeral breeding sites. We demonstrate that historicalAnophelesmalaria vectors are still widespread in Northern Italy.
Coevolutionary phage training leads to greater bacterial suppression and delays the evolution of phage resistance
Authors: Borin Joshua M. , Avrani Sarit , Barrick Jeffrey E. , Petrie Katherine L. , Meyer Justin R. 
Published: November 2020

AbstractThe evolution of antibiotic resistant bacteria threatens to become the leading cause of worldwide mortality. This crisis has renewed interest in the practice of phage therapy. Yet, bacteria’s capacity to evolve resistance is likely to debilitate this therapy as well. To combat the evolution of phage resistance and improve treatment outcomes, many have suggested leveraging phages’ ability to counter resistance by evolving phages on target hosts before using them in therapy (phage training). We found that during in vitro experiments, a phage trained for 28 days suppressed bacteria ∼1000-fold for 3-8 times longer than its untrained ancestor. This extension was due to a delay in the evolution of resistance. Several factors contributed to this prolonged suppression. Mutations that confer resistance to trained phages are ∼100× less common and, while the target bacterium can evolve complete resistance to the untrained phage in a single step, multiple mutations are required to evolve complete resistance to trained phages. Mutations that confer resistance to trained phages are more costly than mutations for untrained phage resistance. And when resistance does evolve, trained phages are better able to suppress these forms of resistance. One way the trained phage improved was through recombination with a gene in a defunct prophage in the host genome, which doubled phage fitness. This direct transfer of information encoded by the host but originating from a relict phage provides a previously unconsidered mode of training phage. Overall, we provide a case study for successful phage training and uncover mechanisms underlying its efficacy.Significance StatementThe evolution of antibiotic resistant bacteria threatens to claim over 10 million lives annually by 2050. This crisis has renewed interest in phage therapy, the use of bacterial viruses to treat infections. A major barrier to successful phage therapy is that bacteria readily evolve phage resistance. One idea proposed to combat resistance is “training” phages by using their natural capacity to evolve to counter resistance. Here, we show that training phages by coevolving them with their host for one month enhanced their capacity for suppressing bacterial growth and delayed the emergence of resistance. Enhanced suppression was caused by several mechanisms, suggesting that the coevolutionary training protocol produces a robust therapeutic that employs complementary modes of action.
Measuring mutagenicity in ecotoxicology: A case study of Cd exposure inChironomus riparius
Authors: Doria Halina Binde , Waldvogel Ann-Marie , Pfenninger Markus 
Published: November 2020

AbstractExisting mutagenicity tests for metazoans lack the direct observation of enhanced germline mutation rates after exposure to anthropogenic substances, therefore being inefficient. Cadmium (Cd) is a metal described as a mutagen in mammalian cells and listed as a group 1 carcinogenic and mutagenic substance. But Cd mutagenesis mechanism is not yet clear. Therefore, in the present study, we propose a method coupling short-term mutation accumulation (MA) lines with subsequent whole genome sequencing (WGS) and a dedicated data analysis pipeline to investigate if chronic Cd exposure onChironomus ripariuscan alter the rate at whichde novopoint mutations appear. Results show that Cd exposure did not affect the basal germline mutation rate nor the mutational spectrum inC. riparius, thereby arguing that exposed organisms might experience a range of other toxic effects before any mutagenic effect may occur. We show that it is possible to establish a practical and easily implemented pipeline to rapidly detect germ cell mutagens in a metazoan test organism. Furthermore, our data implicate that it is questionable to transfer mutagenicity assessments based onin vitromethods to complex metazoans.Main find of the workCd chronic exposure under environmental realistic concentrations did not exert mutagenicity; It is questionable to transferin vitromutagenicity assessments to complex metazoans.
Pick Your Poison: Molecular Evolution of Venom Proteins in Asilidae (Insecta: Diptera)
Authors: Cohen Chris M. , Cole T. Jeffrey , Brewer Michael S. 
Published: November 2020

AbstractRobber flies are an understudied family of venomous, predatory Diptera. With the recent characterization of venom from three asilid species, it is possible for the first time to study the molecular evolution of venom genes in this unique lineage. To accomplish this, a novel whole-body transcriptome ofEudioctria mediawas combined with 10 other publicly available asiloid thoracic or salivary gland transcriptomes to identify putative venom gene families and assess evidence of pervasive positive selection. A total of 348 gene families of sufficient size were analyzed, and 33 of these were predicted to contain venom genes. We recovered 151 families containing homologs to previously described venoms, and 40 of these were uniquely gained in Asilidae. Our gene family clustering suggests that many asilidin venom gene families are not natural groupings as originally delimited. Additionally, robber-fly venoms have relatively few sites under positive selection, consistent with the hypothesis that the venom of older lineages are dominated by negative selection acting to maintain toxic function.
Inflammatory cytokine profile and plasticity of brain and spinal microglia in response to ATP and glutamate
Authors: Jesudasan Sam Joshva Baskar , Gupta Somnath J , Churchward Matthew A , Todd Kathryn , Winship Ian R 
Published: November 2020

AbstractMicroglia are the primary cells in the central nervous system that identify and respond to injury or damage. Such a perturbation in the nervous system induces the release of molecules including ATP and glutamate that act as damage-associated molecular patterns (DAMPs). DAMPs are detected by microglia, which then regulate the inflammatory response in a manner sensitive to their surrounding environment. The available data indicates that ATP and glutamate can induce the release of pro inflammatory factors TNF (tumor necrosis factor), IL-1β (interleukin 1 beta) and NO (nitric oxide) from microglia. However, non-physiological concentrations of ATP and glutamate were often used to derive these insights. Here, we have compared the response of spinal cord microglia (SM) relative to brain microglia (BM) using physiologically relevant concentrations of glutamate and ATP that mimic injured conditions in the central nervous system. The data show that ATP and glutamate are not significant modulators of the release of cytokines from either BM or SM. Consistent with previous studies, spinal microglia exhibited a general trend towards reduced release of inflammatory cytokines relative to brain-derived microglia. Moreover, we demonstrate that the responses of microglia to these DAMPs can be altered by modifying the biochemical milieu in their surrounding environment. Preconditioning brain derived microglia with media from spinal cord derived mixed glial cultures shifted their release of IL-ß, IL-6 and IL-10 to a less inflammatory phenotype consistent with a spinal microglia.
Structure of the endocytic adaptor complex reveals the basis for efficient membrane anchoring during clathrin-mediated endocytosis
Authors: Lizarrondo Javier , Klebl David P. , Niebling Stephan , Abella Marc , Schroer Martin A. , Mertens Haydyn D.T. , Veith Katharina , Svergun Dmitri I. , Skruzny Michal , Sobott Frank , Muench Stephen , Garcia-Alai Maria M. 
Published: November 2020

AbstractDuring clathrin-mediated endocytosis, a complex and dynamic network of protein-membrane interactions cooperate to achieve membrane invagination. Throughout this process, middle coat adaptors, Sla2 and Ent1, must remain attached to the plasma membrane to transmit force from the actin cytoskeleton required for successful membrane invagination. Here, we present a cryoEM structure of a 16-mer complex of membrane binding domains from Sla2 and Ent1 that anchors to the plasma membrane. Detailed mutagenesisin vitroandin vivoof the tetramer interfaces delineate the key interactions for complex formation and deficient cell growth phenotypes demonstrate the biological relevance of these interactions. Finally, time-resolved experimentsin solutionsuggest that adaptors have evolved to achieve a fast subsecond timescale assembly in the presence of PIP2. Together, these findings provide a molecular understanding of an essential piece for the molecular puzzle of clathrin-coated sites.
Kinetic model of small RNA-mediated regulation suggests that a small RNA can regulate co-transcriptionally
Authors: Reyer Matthew A. , Chennakesavalu Shriram , Heideman Emily M. , Ma Xiangqian , Bujnowska Magda , Hong Lu , Dinner Aaron R. , Vanderpool Carin K. , Fei Jingyi 
Published: November 2020

AbstractSmall RNAs (sRNAs) are important regulators of gene expression in bacteria, particularly during stress responses. Many genetically and biochemically well characterized sRNAs regulate gene expression post-transcriptionally, by affecting translation and degradation of the target mRNA after they bind to their targets through base pairing. However, how regulation at each of these levels quantitatively contributes to the overall efficacy of sRNA-mediated regulation is not well understood. Here we present a general approach combining imaging and mathematical modeling to determine kinetic parameters at different levels of sRNA-mediated gene regulation. Unexpectedly, our data reveal that certain previously characterized sRNAs are able to regulate some targets co-transcriptionally, rather strictly post-transcriptionally, and suggest that sRNA-mediated regulation can occur early in the mRNA’s lifetime, perhaps as soon as the sRNA binding site is transcribed. In addition, our data suggest several important kinetic steps that may determine the efficiency and differential regulation of multiple mRNA targets by an sRNA. Particularly, binding of sRNA to the target mRNA is likely the rate-limiting step and may dictate the regulation hierarchy observed within an sRNA regulon.
Effect of entrepreneurial competencies on micro-enterprises income and assets in Malaysia
Authors: Mustapha Wan Nurulasiah Wan , Al Mamun Abdullah , Mansori Shaheen , Balasubramaniam Sudesh 
Published: November 2020

PurposeThis study aims to provide a foundation for the performance-focused micro-entrepreneurship development program; hence, this study is designed to investigate the effect of selected entrepreneurial competencies on micro-enterprise income and assets in Malaysia.Design/methodology/approachThis study adopts the cross-sectional design, and the quantitative data was collected from 300 randomly selected micro-entrepreneurs from the list of participants of several micro-enterprise development programs offered in Peninsular Malaysia.FindingsFindings revealed that micro-entrepreneur’s commitment competency and opportunity recognition competency have a significant positive effect on micro-enterprise income, whereas only opportunity recognition competency has a significant positive effect on the net worth of micro-enterprise assets.Originality/valueThis study examined the effect of key elements of entrepreneurial competencies on micro-enterprise income and asset, which provides the foundation for a performance-focused micro-entrepreneurship development program designed to enhance the performance of micro-enterprises in Malaysia.
Prospects and challenges of entrepreneurship internationalization on the competitiveness of SMEs
Authors: Olaore Gbemi Oladipo , Adejare Bimbo Onaolapo , Udofia Ekpenyong Ekpenyong 
Published: November 2020

Purpose
Global presence pursuit by Nigerian firms has increased the inquiry into internationalization. While a few implement regional presence, the pros and cons of full internationalization are evaluated. Giving the scarce empirical research, this paper aims to add to scholarly works and knowledge on internationalization and establish regional internationalization as the feasible option for Nigerian firms.

Design/methodology/approach
Random and stratified sampling techniques were used. Data collection was conducted with questionnaire copies and analyzed with confirmatory factor analysis and structural equation model.

Findings
Internationalization strategy enhances small and medium enterprises (SME’s) competitive advantage, and full internationalization seems unrealistic for Nigerian firms; however, regional internationalization is the bedrock for full internationalization. Finally, the nature of the Nigerian business environment developed an increased value creation process in SMEs through increased flexibility and problem-solving abilities.

Practical implications
SMEs should internationalize partially, and critically evaluate socio-cultural and institutional environmental challenges in this study, to enable them to strategize for full internationalization.

Originality/value
The study demonstrates that the only way to fast track the internationalization drive of SME’s in Nigeria is first to embrace regional internationalization because it is difficult to achieve full internationalization at a go. Then, apply appropriate strategies to embrace full internationalization in the nearest future.