Search results for " sign"
showing 10 items of 3133 documents
Evaluating responses to temperature during pre-metamorphosis and carry-over effects at post-metamorphosis in the wood tiger moth (Arctia plantaginis)
2019
Insect metamorphosis is one of the most recognized processes delimiting transitions between phenotypes. It has been traditionally postulated as an adaptive process decoupling traits between life stages, allowing evolutionary independence of pre- and post-metamorphic phenotypes. However, the degree of autonomy between these life stages varies depending on the species and has not been studied in detail over multiple traits simultaneously. Here, we reared full-sib larvae of the warningly coloured wood tiger moth ( Arctia plantaginis ) in different temperatures and examined their responses for phenotypic (melanization change, number of moults), gene expression (RNA-seq and qPCR of candidate ge…
Arabidopsis RCD1 coordinates chloroplast and mitochondrial functions through interaction with ANAC transcription factors
2019
Reactive oxygen species (ROS)-dependent signaling pathways from chloroplasts and mitochondria merge at the nuclear protein RADICAL-INDUCED CELL DEATH1 (RCD1). RCD1 interacts in vivo and suppresses the activity of the transcription factors ANAC013 and ANAC017, which mediate a ROS-related retrograde signal originating from mitochondrial complex III. Inactivation of RCD1 leads to increased expression of mitochondrial dysfunction stimulon (MDS) genes regulated by ANAC013 and ANAC017. Accumulating MDS gene products, including alternative oxidases (AOXs), affect redox status of the chloroplasts, leading to changes in chloroplast ROS processing and increased protection of photosynthetic apparatus.…
Calcium—Nutrient and Messenger
2019
Calcium is an essential element needed for growth and development of plants under both non-stressed and stress conditions. It thereby fulfills a dual function, being not only an important factor for cell wall and membrane stability, but also serving as a second messenger in many developmental and physiological processes, including the response of plants to biotic stress. The perception of non-self hereby induces an influx of calcium ions (Ca2+) into the cytosol, which is decoded into downstream responses ultimately leading to defense. Maintaining intracellular Ca2+ homeostasis is crucial for the ability to generate this signal. This review will describe the current knowledge of the mechanis…
Body growth and its implications in population dynamics of Acanthodactylus erythrurus (Schinz, 1834) in the Eastern Iberian peninsula
2019
Abstract We calculated growth rate for the spiny-footed lizard (Acanthodactylus erythrurus) inhabiting coastal eastern Spain from long-term mark-recapture data. Growth curves differ between sexes, with males growing faster than females and achieving larger size maximums. In this population each sex reaches maturity at about 300 days of age, approximately 34% faster than males, and 28% faster than females studied in a population further south and west in Iberia. Our logarithmic growth model has an accuracy of 96.8% and high statistical significance ( for males and for females). Although both the exponential curve of “best fit” for growth estimated for males (), and the linear curve of “best …
Involvement of the glutamate receptor AtGLR3.3 in plant defense signaling and resistance toHyaloperonospora arabidopsidis
2013
Like their animal counterparts, plant glutamate receptor-like (GLR) homologs are intimately associated with Ca(2+) influx through plasma membrane and participate in various physiological processes. In pathogen-associated molecular patterns (PAMP)-/elicitor-mediated resistance, Ca(2+) fluxes are necessary for activating downstream signaling events related to plant defense. In this study, oligogalacturonides (OGs), which are endogenous elicitors derived from cell wall degradation, were used to investigate the role of Arabidopsis GLRs in defense signaling. Pharmacological investigations indicated that GLRs are partly involved in free cytosolic [Ca(2+)] ([Ca(2+)]cyt) variations, nitric oxide (N…
Calcium homeostasis in plant cell nuclei
2009
International audience; In plant cells, calcium-based signaling pathways are involved in a large array of biological processes, including cell division, polarity, growth, development and adaptation to changing biotic and abiotic environmental conditions. Free calcium changes are known to proceed in a nonstereotypical manner and produce a specific signature, which mirrors the nature, strength and frequency of a stimulus. The temporal aspects of calcium signatures are well documented, but their vectorial aspects also have a profound influence on biological output. Here, we will focus on the regulation of calcium homeostasis in the nucleus. We will discuss data and present hypotheses suggestin…
Cryptogein, a fungal elicitor, remodels the phenylpropanoid metabolism of tobacco cell suspension cultures in a calcium-dependent manner
2010
Plant cells use calcium-based signalling pathways to transduce biotic and/or abiotic stimuli into adaptive responses. However, little is known about the coupling between calcium signalling, transcriptional regulation and the downstream biochemical processes. To understand these relationships better, we challenged tobacco BY-2 cells with cryptogein and evaluated how calcium transients (monitored through the calcium sensor aequorin) impact (1) transcript levels of phenylpropanoid genes (assessed by RT-qPCR); and (2) derived-phenolic compounds (analysed by mass spectrometry). Most genes of the phenylpropanoid pathway were up-regulated by cryptogein and cell wall-bound phenolic compounds accumu…
Cytosolic pH regulates root water transport during anoxic stress through gating of aquaporins.
2003
Flooding of soils results in acute oxygen deprivation (anoxia) of plant roots during winter in temperate latitudes, or after irrigation1, and is a major problem for agriculture. One early response of plants to anoxia and other environmental stresses is downregulation of water uptake due to inhibition of the water permeability (hydraulic conductivity) of roots (Lpr)2,3,4,5. Root water uptake is mediated largely by water channel proteins (aquaporins) of the plasma membrane intrinsic protein (PIP) subgroup6,7,8. These aquaporins may mediate stress-induced inhibition of Lpr2,4,9 but the mechanisms involved are unknown. Here we delineate the whole-root and cell bases for inhibition of water upta…
Constitutive expression of clathrin hub hinders elicitor-induced clathrin-mediated endocytosis and defense gene expression in plant cells.
2012
International audience; Endocytosis has been recently implicated in the signaling network associated with the recognition of microbes by plants. In a previous study, we showed that the elicitor cryptogein was able to induce clathrin-mediated endocytosis (CME) in tobacco suspension cells. Herein, we investigate further the induced CME by means of a GFP-tagged clathrin light chain and a CME inhibitor, the hub domain of clathrin heavy chain. Hub constitutive expression does affect neither cell growth nor constitutive endocytosis but abolishes cryptogein-induced CME. Such an inhibition has no impact on early events in the cryptogein signaling pathway but reduces the expression of defense-associ…
Decoding Group Vocalizations: The Acoustic Energy Distribution of Chorus Howls Is Useful to Determine Wolf Reproduction
2016
Population monitoring is crucial for wildlife management and conservation. In the last few decades, wildlife researchers have increasingly applied bioacoustics tools to obtain information on several essential ecological parameters, such as distribution and abundance. One such application involves wolves (Canis lupus). These canids respond to simulated howls by emitting group vocalizations known as chorus howls. These responses to simulated howls reveal the presence of wolf litters during the breeding period and are therefore often used to determine the status of wolf populations. However, the acoustic structure of chorus howls is complex and discriminating the presence of pups in a chorus i…