Search results for " Physiologic"
showing 10 items of 2104 documents
Combined phosphate and nitrogen limitation generates a nutrient stress transcriptome favorable for arbuscular mycorrhizal symbiosis in M edicago trun…
2013
International audience; Arbuscular mycorrhizal (AM) symbiosis is stimulated by phosphorus (P) limitation and contributes to P and nitrogen (N) acquisition. However, the effects of combined P and N limitation on AM formation are largely unknown. Medicago truncatula plants were cultivated in the presence or absence of Rhizophagus irregularis (formerly Glomus intraradices) in P-limited (LP), N-limited (LN) or combined P- and N-limited (LPN) conditions, and compared with plants grown in sufficient P and N. The highest AM formation was observed in LPN, linked to systemic signaling by the plant nutrient status. Plant free phosphate concentrations were higher in LPN than in LP, as a result of cros…
Invasion triple trouble : environmental fluctuations, fluctuation-adapted invaders and fluctuation-mal-adapted communities all govern invasion success
2017
AbstractIt has been suggested that climate change will lead to increased environmental fluctuations, which will undoubtedly have evolutionary consequences for all biota. For instance, fluctuations can directly increase the risk of invasions of alien species into new areas, as these species have repeatedly been proposed to benefit from disturbances. At the same time increased environmental fluctuations may also select for better invaders. However, selection by fluctuations may also influence the resistance of communities to invasions, which has rarely been tested. We tested eco-evolutionary dynamics of invasion with bacterial clones, evolved either in constant or fluctuating temperatures, an…
Ocean acidification does not impair predator recognition but increases juvenile growth in a temperate wrasse off CO2seeps
2017
8 pages, 4 figures, supplementary data https://doi.org/10.1016/j.marenvres.2017.10.013
Distribution of sea urchins living near shallow water CO2 vents is dependent upon species acid-base and ion-regulatory abilities.
2013
To reduce the negative effect of climate change on Biodiversity, the use of geological CO2 sequestration has been proposed; however leakage from underwater storages may represent a risk to marine life. As extracellular homeostasis is important in determining species' ability to cope with elevated CO2, we investigated the acid-base and ion regulatory responses, as well as the density, of sea urchins living around CO2 vents at Vulcano, Italy. We conducted in situ transplantation and field-based laboratory exposures to different pCO2/pH regimes. Our results confirm that sea urchins have some ability to regulate their extracellular fluid under elevated pCO2. Furthermore, we show that even in cl…
Is it advantageous for Atlantic salmon to be triploid at lower temperatures?
2020
Marine organisms living at low temperatures tend to have larger genomes and larger cells which suggest that these traits can be beneficial in colder environments. In fish, triploidy (three complete sets of chromosomes) can be induced experimentally following fertilization, which provides a model system to investigate the hypothesis that larger cells and genomes offers a physiological advantage at low temperatures. We tested this hypothesis by measuring metabolic rates and swimming performance of diploid and triploid Atlantic salmon (Salmo salar) post smolts acclimated to 3 or 10.5 °C. At 10.5 °C, triploids had significantly lower maximum metabolic rates which resulted in a lower aerobic sco…
Biological films adhering to the oral soft tissues: Structure, composition, and potential impact on taste perception
2018
The role of free-flowing saliva in taste perception is increasingly recognized, but saliva is also present in the mouth as films intimately associated to soft or hard tissues. On mucosal surfaces, particularly on the tongue, the structure and composition of such films (including its microbial constitutive part) may play a particular role in the sense of taste due to their proximity with the taste anatomical structures. This review compiles the current knowledge on the structure of biological films adhering to oral mucosae and on their biochemical and microbiological composition, before presenting possible implications for taste perception. PRACTICAL APPLICATIONS: The understanding of the ro…
Arabidopsis thaliana nicotianamine synthase 4 is required for proper response to iron deficiency and to cadmium exposure.
2013
International audience; The nicotianamine synthase (NAS) enzymes catalyze the formation of nicotianamine (NA), a non-proteinogenic amino acid involved in iron homeostasis. We undertook the functional characterization of AtNAS4, the fourth member of the Arabidopsis thaliana NAS gene family. A mutant carrying a T-DNA insertion in AtNAS4 (atnas4), as well as lines overexpressing AtNAS4 both in the atnas4 and the wild-type genetic backgrounds, were used to decipher the role of AtNAS4 in NA synthesis, iron homeostasis and the plant response to iron deficiency or cadmium supply. We showed that AtNAS4 is an important source for NA. Whereas atnas4 had normal growth in iron-sufficient medium, it dis…
New frontiers in nitric oxide biology in plant.
2011
Preface; International audience
The Sulfated Laminarin Triggers a Stress Transcriptome before Priming the SA- and ROS-Dependent Defenses during Grapevine's Induced Resistance agains…
2018
Grapevine (Vitis vinifera) is susceptible to many pathogens which cause significant losses to viticulture worldwide. Chemical control is available, but agro-ecological concerns have raised interest in alternative methods, especially in triggering plant immunity by elicitor treatments. The β-glucan laminarin (Lam) and its sulfated derivative (PS3) have been previously demonstrated to induce resistance in grapevine against downy mildew (Plasmopara viticola). However, if Lam elicits classical grapevine defenses such as oxidative burst, pathogenesis-related (PR)-proteins and phytoalexin production, PS3 triggered grapevine resistance via a poorly understood priming phenomenon. The aim of this st…
Rapid induction of immune density-dependent prophylaxis in adult social insects.
2009
The innate immune system provides defence against parasites and pathogens. This defence comes at a cost, suggesting that immune function should exhibit plasticity in response to variation in environmental threats. Density-dependent prophylaxis (DDP) has been demonstrated mostly in phase-polyphenic insects, where larval group size determines levels of immune function in either adults or later larval instars. Social insects exhibit extreme sociality, but DDP has been suggested to be absent from these ecologically dominant taxa. Here we show that adult bumble-bee workers ( Bombus terrestris ) exhibit rapid plasticity in their immune function in response to social context. These results sugges…