Plant–pollinator interactions between generalists persist over time and space

Generalist species are the linchpins of networks, as they are important for maintaining network structure and function. Previous studies have shown that interactions between generalists tend to occur consistently across years and sites. However, the link between temporal and spatial interaction persistence across scales remains unclear. To address this gap, we collected data on plant–pollinator interactions throughout the flowering period for 5 yr across six plots in a subalpine meadow in the Rocky Mountains. We found that interactions between generalists tended to persist more in time and space such that interactions near the network core were more frequently recorded across years, within seasons, and among plots. We posit that species' tolerance of environmental variation across time and space plays a key role in generalization by regulating spatiotemporal overlap with interaction partners. Our results imply a role of spatiotemporal environmental variation in organizing species interactions, marrying niche concepts that emphasize species environmental constraints and their community role.Fil: Resasco, Julian. State University of Colorado at Boulder; Estados UnidosFil: Chacoff, Natacha Paola. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Vazquez, Diego P.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin

Drivers of macroinvertebrate metacommunity structure in Tierra del Fuego rivers

Among the different mechanisms that shape metacommunity structure, species sorting and mass effects are the moststudied and often reported mechanisms. Species sorting it?s related with environmental filtering while mass effects isrelated with high dispersion between communities, that ultimately overrides environmental control. In this paper weaimed at studying metacommunity patterns of stream invertebrates in Tierra del Fuego Island at different spatial scales(province, ecoregion and catchment) and at different positions along the river network, (upstream, mid-stream anddownstream segments) in order to understand the mechanisms driving metacommunity structure. For this purpose, weused complementary approaches based on the analysis of beta diversity index as well as its turnover and nestednesscomponents, which are associated with the two main underlying mechanisms of metacommunity structure (speciessorting and mass effect). Our results indicate that species sorting is the preponderant mechanism structuringmacroinvertebrate metacommunities at larger spatial scales, with an increased importance of mass effects at smallerscales (e.g. catchment). Metacommunities at different positions on the river network exhibit similar values of total betadiversity, turnover and nestedness components. On the other hand, turnover and total beta diversity increased withspatial extent, while nestedness remained constant. Those results suggest that at the catchment scale and along thelongitudinal axis of the rivers other mechanisms, like randomness and species dispersal, are more important inshaping the macroinvertebrate metacommunity.Fil: Fernandez, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Villatarco Vazquez, Amanda Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; ArgentinaFil: Albariño, Ricardo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Free volatie compounds of cv. Pedro Giménez (Vitis vinifera L.) white grape must grown in San Juan, Argentina.

The free aromatic composition of must from Pedro Giménez grapes, grown in San Juan, Argentina, was characterised. Samples from the vintages of 2008 and 2009 were analysed by gas chromatography-mass spectrometry-solid phase microextraction (GC-MS-SPME). Higher alcohols, terpenes, C13-norisoprenoids, esters, aldehydes and ketones were quantifed. The calculation of the odour activity values (OAVs) revealed that β-damascenone, α-ionone, β-linalool, geraniol, ethyl butanoate, hexanoate and octanoate were the most prevalent aroma-active compounds of the grape variety. However, the remaining 42 aromatic compounds that registered OAVs less than 1 could potentially contribute to the favour of Pedro Giménez grapes. The measured monoterpene levels indicate that the Pedro Giménez grape can be considered a neutral variety. This is the frst report describing the main potential free aroma contributors of Pedro Giménez grapes in two consecutive years.Fil: Maturano, Yolanda Paola. Universidad Nacional de San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; ArgentinaFil: Nally, Maria Cristina. Universidad Nacional de San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; ArgentinaFil: Toro, Maria Eugenia. Universidad Nacional de San Juan; ArgentinaFil: Castellanos, Lucia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Vazquez, Fabio. Universidad Nacional de San Juan; Argentin

Prostate tumor growth is impaired by CtBP1 depletion in high-fat diet-fed mice

Clinical and epidemiologic data suggest that obesity is associated with more aggressive forms of prostate cancer, poor prognosis, and increased mortality. C-terminal-binding protein 1 (CtBP1) is a transcription repressor of tumor suppressor genes and is activated by NADH binding. High calorie intake decreases intracellular NAD(+)/NADH ratio. The aim of this work was to assess the effect of high-fat diet (HFD) and CtBP1 expression modulation over prostate xenograft growth. We developed a metabolic syndrome-like disease in vivo model by feeding male nude mice with HFD during 16 weeks. Control diet (CD)-fed animals were maintained at the same conditions. Mice were inoculated with PC3 cells stable transfected with shCtBP1 or control plasmids. Genome-wide expression profiles and Gene Set Enrichment Analysis (GSEA) were performed from PC3.shCtBP1 versus PC3.pGIPZ HFD-fed mice tumors.Fil: Moiola, Cristian Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: de Luca, Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica; ArgentinaFil: Zalazar, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Cotignola, Javier Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Rodríguez Seguí, Santiago Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular; ArgentinaFil: Gardner, Kevin. National Institutes of Health; Estados UnidosFil: Meissl, Roberto Jose. Academia Nacional de Medicina de Buenos Aires; ArgentinaFil: Vallecorsa, Pablo Daniel. Academia Nacional de Medicina de Buenos Aires; ArgentinaFil: Pignataro, Omar Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Mazza, Osvaldo. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Vazquez, Elba Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: de Siervi, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin

Selection of Native Non-Saccharomyces Yeasts with Biocontrol Activity against Spoilage Yeasts in Order to Produce Healthy Regional Wines

Two major spoilage yeasts in the wine industry, Brettanomyces bruxellensis and Zygosaccharomyces rouxii, produce off-flavors and gas, causing considerable economic losses. Traditionally, SO2 has been used in winemaking to prevent spoilage, but strict regulations are in place regarding its use due to its toxic and allergenic effects. To reduce its usage researchers have been searching for alternative techniques. One alternative is biocontrol, which can be used either independently or in a complementary way to chemical control (SO2). The present study analyzed 122 native non-Saccharomyces yeasts for their biocontrol activity and their ability to be employed under fermentation conditions, as well as certain enological traits. After the native non-Saccharomyces yeasts were assayed for their biocontrol activity, 10 biocontroller yeasts were selected and assayed for their ability to prevail in the fermentation medium, as well as with respect to their corresponding positive/negative contribution to the wine. Two yeasts that satisfy these characteristics were Wickerhamomyces anomalus BWa156 and Metschnikowia pulcherrima BMp29, which were selected for further research in application to mixed fermentations.Fil: Kuchen, Benjamín. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Maturano, Yolanda Paola. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Mestre Furlani, María Victoria. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Combina, Mariana. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-San Juan. Estación Experimental Agropecuaria Mendoza; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; ArgentinaFil: Toro, Maria Eugenia. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; ArgentinaFil: Vazquez, Fabio. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Biotecnología; Argentin

Selection of non-Saccharomyces yeasts to be used in grape musts with high alcoholic potential: A strategy to obtain wine with reduced etanol content

Ethanol content of wine has increased over the last decades as consequence of searching phenolic maturity, requiring increased grape maturity. This may result in the production of wines with excessive alcohol levels (sometimes more than 15% (v/v)), sluggish and stuck fermentations and excessive volatile acidity. Many strategies to reduce ethanol in wines are being studied, and microbial methods have some additional advantages. However, because of the broad intra- and interspecies variability, new selection criteria should be included. Therefore, the goal of the present work was to design and evaluate a simple and integral procedure for non-Saccharomyces yeast selection. This strategy allowed selection of yeasts that presented successful implantation in grape must with high alcohol potential and their use in co-cultures could reduce the ethanol in wines. A total of 114 native non-Saccharomyces yeasts were assayed to determine their respiratory, fermentative and physiological characteristics of enological interest. Hanseniaspora uvarum BHu9 and BHu11, H. osmophila BHo51, Starmerella bacillaris BSb55 and Candida membranaefaciens BCm71 were selected as candidates to design co-culture startersEEA MendozaFil: Mestre Furlani, Maria Victoria. Universidad Nacional de San Juan. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Maturano, Yolanda Paola. Universidad Nacional de San Juan. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Combina, Mariana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mercado, Laura Analia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; ArgentinaFil: Toro, Maria Eugenia. Universidad Nacional de San Juan. Instituto de Biotecnología; ArgentinaFil: Vazquez, Fabio. Universidad Nacional de San Juan. Instituto de Biotecnología; Argentin

Dynamic coregulatory complex containing BRCA1, E2F1 and CtIP controls ATM transcription

Chromosomal instability is a key feature in cancer progression. Recently we have reported that BRCA1 regulates the transcription of several genes in prostate cancer, including ATM (ataxia telangiectasia mutated). Although it is well accepted that ATM is a pivotal mediator in genotoxic stress, it is unknown whether ATM transcription is regulated during the molecular response to DNA damage. Here we investigate ATM transcription regulation in human prostate tumor PC3 cell line. We have found that doxorubicin and mitoxantrone repress ATM transcription in PC3 cells but etoposide and methotrexate do not affect ATM expression. We have demonstrated that BRCA1 binds to ATM promoter and after doxorubicin exposure, it is released. BRCA1 overexpression increases ATM transcription and this enhancement is abolished by BRCA1 depletion. Moreover, BRCA1-BRCT domain loss impairs the ability of BRCA1 to regulate ATM promoter activity, strongly suggesting that BRCT domain is essential for ATM regulation by BRCA1. BRCA1-overexpressing PC3 cells exposed to KU55933 ATM kinase inhibitor showed significant decreased ATM promoter activity compared to untreated cells, suggesting that ATM transcriptional regulation by BRCA1 is partially mediated by the ATM kinase activity. In addition, we have demonstrated E2F1 binding to ATM promoter before and after doxorubicin exposure. E2F1 overexpression diminishes ATM transcription after doxorubicin exposure which is impaired by E2F1 dominant negative mutants. Finally, the co-regulator of transcription CtIP increases ATM transcription. CtIP increases ATM transcription. Altogether, BRCA1/E2F1/CtIP binding to ATM promoter activates ATM transcription. Doxorubicin exposure releases BRCA1 and CtIP from ATM promoter still keeping E2F1 recruited and, in turn, represses ATM expression.Fil: Moiola, Cristian Pablo. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: de Luca, Paola. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cotignola, Javier Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; ArgentinaFil: Gardner, Kevin. No especifíca;Fil: Vazquez, Elba Susana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; ArgentinaFil: de Siervi, Adriana. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Toward application of biocontrol to inhibit wine spoilage yeasts: The use of statistical designs for screening and optimisation

Spoilage yeasts generate considerable economic losses in the wine industry, and although sulphur dioxide (SO2) is traditionally used for control, its use has become controversial because of its negative effects on health. Biocontrol has emerged as a partial alternative to SO2, and most research has focused on the selection of biocontrol yeasts and/or the mechanisms involved, while little research has been directed to the environmental conditions that make biocontrol effective for application. When there are two or more interacting yeasts, the physicochemical factors that affect their antagonism are many and therefore the application of biocontrol is complex. To reduce SO2, the present study aimed to elucidate biocontrol mechanisms of two yeast interactions and to establish optimal physicochemical conditions for biocontrol of the spoilage yeast during grape must fermentation. Through the use of statistical design, it was possible to find relevant physicochemical factors and optimise them. Wickerhamomyces anomalus “BWa156” developed an active supernatant against Zygosaccharomyces rouxii “BZr6” while supernatant from Metschnikowia pulcherrima “BMp29” was ineffective. In mixed must fermentations, the first interaction (BWa156 vs. BZr6) showed fewer physicochemical factors impacting biocontrol compared to the second interaction (BMp29 vs. BZr6). However, the fewer factors of the first interaction had a stronger effect on the decline in the spoilage population. Validations showed that the optimal conditions for biocontrol with the first interaction could be predicted. Analysis of the results with BWa156 vs. BZr6 and BMp29 vs. BZr6 suggests that the first interaction is a competition that includes a killer toxin, while the second interaction involves competition for iron resources. Response surface methodology (RSM) allowed a reduction in the number of experiments and permitted to find the optimal biocontrol conditions (SO2: 0 mg mL-1; pH: 3.7; Reducing sugars: 23 °Brix) for the interaction between BWa156 and BZr6.Fil: Kuchen, Benjamín. Departamento de Ingenieria Agronomica ; Facultad de Ingenieria ; Universidad Nacional de San Juan; ArgentinaFil: Vazquez, Fabio. Universidad Nacional de San Juan; ArgentinaFil: Maturano, Yolanda Paola. Departamento de Ingenieria Agronomica ; Facultad de Ingenieria ; Universidad Nacional de San Juan; ArgentinaFil: Scaglia, Gustavo Juan Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan; Faculta de Ingeniaría; Instituto de Ingeniería Química; ArgentinaFil: Pera, Licia Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Vallejo, Martha Dina. Universidad Nacional de San Juan; Argentin

Monitoring of killer yeast populations in mixed cultures: influence of incubation temperature of microvinifications samples

Killer yeasts are frequently used to combat and prevent contamination by wild-type yeasts during wine production and they can even dominate the wine fermentation. Stuck and sluggish fermentations can be caused by an unbalanced ratio of killer to sensitive yeasts in the bioreactor, and therefore it is important to determine the proportion of both populations. The aim of this study was to provide a simple tool to monitor killer yeast populations during controlled mixed microvinifications of killer and sensitive Saccharomyces cerevisiae. Samples were periodically extracted during vinification, seeded on Petri dishes and incubated at 25 and 37 °C; the latter temperature was assayed for possible inactivation of killer toxin production. Colonies developed under the described conditions were randomly transferred to killer phenotype detection medium. Significant differences in the killer/sensitive ratio were observed between both incubation temperatures in all microvinifications. These results suggest that 37 °C seems a better option to determine the biomass of sensitive yeasts, in order to avoid underestimation of sensitive cells in the presence of killer yeasts during fermentations. Incubation at a toxin-inhibiting temperature clearly showed the real ratio of killer to sensitive cells in fermentation systems.Fil: Maturano, Yolanda Paola. Universidad Nacional de San Juan. Instituto de Biotecnología; ArgentinaFil: Nally, María Cristina. Universidad Nacional de San Juan. Instituto de Biotecnología; ArgentinaFil: Toro, María Eugenia. Universidad Nacional de San Juan. Instituto de Biotecnología; ArgentinaFil: Castellanos de Figueroa, Lucía Inés. PROIMI; Argentina. Universidad Nacional de Tucumán. FBQyF; ArgentinaFil: Combina, Mariana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vazquez, Fabio. Universidad Nacional de San Juan. Instituto de Biotecnología; Argentin