Search results for "NAD"
showing 10 items of 2033 documents
Evaluation of the Ability of Polyphenol Extracts of Cocoa and Red Grape to Promote the Antioxidant Response in Yeast Using a Rapid Multiwell Assay
2017
Saccharomyces cerevisiae has been used as a model organism to study the capacity of cocoa and red grape extracts to trigger an antioxidant response. A methodology adapted to microtiter plates has been developed to monitor yeast growth after culture preincubation with food ingredients and exposure to oxidative stress by hydrogen peroxide and menadione. This methodology proved effective in measuring the ability of cocoa and red grape extracts to promote an antioxidant response in yeast, and also the prospect of conducting dose-response studies. Additionally, the method has proven useful to perform studies with mutant strains lacking genes that may be related to the mechanism of action underly…
A genetic study on subtropical Anadenanthera colubrina (Vell.) Brenan var. cebil (Griseb.) Altschul tree from Northwestern Argentina
2017
Anadenanthera colubrina (Vell.) Brenan var. cebil (Griseb.) Altschul is a tree species in South America important for its cultural, economic, and medicinal uses. In addition, it represents a trace in memory of the forests that have decreased over the years and for this reason it is not only interesting to study but also important to preserve the tree species for future generations. In this paper, we have characterized the genetic diversity of four populations. We collected seeds from four different sites: San Bernardo (B), El Cebilar (C), Metán (M), and El Gallinato (G) in Salta Province, North Argentina. We then compared the intergenic transcribed sequences of ribosomal DNA, a known geneti…
The bacterial microbiome of meloidogyne-based disease complex in coffee and tomato
2020
The Meloidogyne-based disease complexes (MDCs) are caused by the interaction of different root-knot nematode species and phytopathogenic fungi. These complexes are devastating several important crops worldwide including tomato and coffee. Despite their relevance, little is known about the role of the bacterial communities in the MDCs. In this study 16s rDNA gene sequencing was used to analyze the bacterial microbiome associated with healthy and infested roots, as well with females and eggs of Meloidogyne enterolobii and M. paranaensis, the causal agents of MDC in tomato and coffee, respectively. Each MDC pathosystems displayed a specific taxonomic diversity and relative abundances constitut…
Mitochondrial heteroplasmy in an avian hybrid form (Passer italiae: Aves, Passeriformes)
2019
Mitochondrial heteroplasmy is the result from biparental transmission of mitochondrial DNA (mtDNA) to the offspring. In such rare cases, maternal and paternal mtDNA is present in the same individual. Though recent studies suggested that mtDNA heteroplasmy might be more common than previously anticipated, that phenomenon is still poorly documented and was mostly detected in case studies on hybrid populations. The Italian sparrow, Passer italiae is a homoploid hybrid form that occurs all across the Italian Peninsula mostly under strict absence of either of its parent species, the house sparrow (P. domesticus) and the Spanish sparrow (P. hispaniolensis). In this study, we document a new case o…
An Arabidopsis Mutant Over-Expressing Subtilase SBT4.13 Uncovers the Role of Oxidative Stress in the Inhibition of Growth by Intracellular Acidificat…
2020
Intracellular acid stress inhibits plant growth by unknown mechanisms and it occurs in acidic soils and as consequence of other stresses. In order to identify mechanisms of acid toxicity, we screened activation-tagging lines of Arabidopsis thaliana for tolerance to intracellular acidification induced by organic acids. A dominant mutant, sbt4.13-1D, was isolated twice and shown to over-express subtilase SBT4.13, a protease secreted into endoplasmic reticulum. Activity measurements and immuno-detection indicate that the mutant contains less plasma membrane H+-ATPase (PMA) than wild type, explaining the small size, electrical depolarization and decreased cytosolic pH of the mutant but not orga…
North African hybrid sparrows (Passer domesticus, P. hispaniolensis) back from oblivion – ecological segregation and asymmetric mitochondrial introgr…
2016
A stabilized hybrid form of the house sparrow (Passer domesticus) and the Spanish sparrow (P. hispaniolensis) is known as Passer italiae from the Italian Peninsula and a few Mediterranean islands. The growing attention for the Italian hybrid sparrow and increasing knowledge on its biology and genetic constitution greatly contrast the complete lack of knowledge of the long-known phenotypical hybrid sparrow populations from North Africa. Our study provides new data on the breeding biology and variation of mitochondrial DNA in three Algerian populations of house sparrows, Spanish sparrows, and phenotypical hybrids. In two field seasons, the two species occupied different breeding habitats: Spa…
Thioredoxin (Trxo1) interacts with proliferating cell nuclear antigen (PCNA) and its overexpression affects the growth of tobacco cell culture.
2017
Thioredoxins (Trxs), key components of cellular redox regulation, act by controlling the redox status of many target proteins, and have been shown to play an essential role in cell survival and growth. The presence of a Trx system in the nucleus has received little attention in plants, and the nuclear targets of plant Trxs have not been conclusively identified. Thus, very little is known about the function of Trxs in this cellular compartment. Previously, we studied the intracellular localization of PsTrxo1 and confirmed its presence in mitochondria and, interestingly, in the nucleus under standard growth conditions. In investigating the nuclear function of PsTrxo1 we identified proliferati…
Rac regulation of NtrbohD, the oxidase responsible for the oxidative burst in elicited tobacco cell
2003
Five cDNAs encoding Rac protein homologues to the Rho-related proteins from plants (Rop) were isolated in tobacco, and the function of one of them, Ntrac5, was studied. The Ntrac5 mRNA is repressed when tobacco leaves and cells are treated with the fungal elicitor cryptogein. Tobacco cells were transformed with sense constructs of Ntrac5 or Ntrac5V15, encoding the native GTP/GDP-bound form of this Rac protein homologue or the constitutively active mutant in its GTP-bound form, respectively. Immunological studies indicate that the corresponding protein is continuously located on the plasma membrane (PM). Both types of transformed cells show the same extra-cellular alkalinization as the contr…
A Tale of Big Game and Small Bugs
1999
Animal populations undergo repetitive cycles of rising and falling numbers. In a Perspective, [Ranta and colleagues][1] discuss the value of time-series analyses for examining the changing dynamics of animal populations. A large time series gathered by the Hudson Bay Company based on the fur trade has provided invaluable data on the rise and fall of the Canadian lynx population from 1821 to the present. Analysis of this time series reveals that climate as well as factors influencing birth and death rates are important in regulating the lynx population ([ Stenseth et al .][2]). In a separate study, mathematical modeling combined with fieldwork revealed the importance of predators in determin…
No growth stimulation of Canada’s boreal forest under half-century of combined warming and CO 2 fertilization
2016
Considerable evidence exists that current global temperatures are higher than at any time during the past millennium. However, the long-term impacts of rising temperatures and associated shifts in the hydrological cycle on the productivity of ecosystems remain poorly understood for mid to high northern latitudes. Here, we quantify species-specific spatiotemporal variability in terrestrial aboveground biomass stem growth across Canada’s boreal forests from 1950 to the present. We use 873 newly developed tree-ring chronologies from Canada’s National Forest Inventory, representing an unprecedented degree of sampling standardization for a large-scale dendrochronological study. We find significa…