Search results for "Vera"
showing 10 items of 5860 documents
Genetic determinants of seed protein plasticity in response to the environment in Medicago truncatula
2021
As the frequency of extreme environmental events is expected to increase with climate change, identifying candidate genes for stabilizing the protein composition of legume seeds or optimizing this in a given environment is increasingly important. To elucidate the genetic determinants of seed protein plasticity, major seed proteins from 200 ecotypes of Medicago truncatula grown in four contrasting environments were quantified after one-dimensional electrophoresis. The plasticity index of these proteins was recorded for each genotype as the slope of Finlay and Wilkinson's regression and then used for genome-wide association studies (GWASs), enabling the identification of candidate genes for d…
A Complex Gene Network Mediated by Ethylene Signal Transduction TFs Defines the Flower Induction and Differentiation in Olea europaea L.
2021
The olive tree (Olea europaea L.) is a typical Mediterranean crop, important for olive and oil production. The high tendency to bear fruits in an uneven manner, defined as irregular or alternate bearing, results in a significant economic impact for the high losses in olives and oil production. Buds from heavy loaded (‘ON’) and unloaded (‘OFF’) branches of a unique olive tree were collected in July and the next March to compare the transcriptomic profiles and get deep insight into the molecular mechanisms regulating floral induction and differentiation. A wide set of DEGs related to ethylene TFs and to hormonal, sugar, and phenylpropanoid pathways was identified in buds collected from ‘OFF’ …
Transcriptional responses to pre-flowering leaf defoliation in grapevine berry from different growing sites, years, and genotypes
2017
Leaf removal is a grapevine canopy management technique widely used to modify the sourceâsink balance and/or microclimate around berry clusters to optimize fruit composition. In general, the removal of basal leaves before flowering reduces fruit set, hence achieving looser clusters, and improves grape composition since yield is generally curtailed more than proportionally to leaf area itself. Albeit responses to this practice seem quite consistent, overall vine performance is affected by genotype, environmental conditions, and severity of treatment. The physiological responses of grape varieties to defoliation practices have been widely investigated, and just recently a whole genome trans…
Hormonal and carbohydrate control of fruit set in avocado ‘Lamb Hass’. A question of the type of inflorescence?
2021
[EN] The avocado tree (Persea americana Mill.) has two types of shoots, indeterminate, which maintain vegetative development from an apical bud, and determinate, which do not have vegetative growth. Indeterminate shoots set fewer fruits than determinate ones, and significantly hasten physiological fruitlet abscission. The competition between vegetative and flower development is accepted as the most reasonable hypothesis to explain the differences. However, our results show that from anthesis until fruit set flowers of indeterminate inflorescences, both those remaining on the tree and those abscised, had a higher sucrose and C6 carbohydrate content than flowers of determinate ones and no dif…
An SNP-based saturated genetic map and QTL analysis of fruit-related traits in Zucchini using Genotyping-by-sequencing
2016
[EN] Background: Cucurbita pepo is a cucurbit with growing economic importance worldwide. Zucchini morphotype is the most important within this highly variable species. Recently, transcriptome and Simple Sequence Repeat (SSR)- and Single Nucleotide Polymorphism (SNP)-based medium density maps have been reported, however further genomic tools are needed for efficient molecular breeding in the species. Our objective is to combine currently available complete transcriptomes and the Zucchini genome sequence with high throughput genotyping methods, mapping population development and extensive phenotyping to facilitate the advance of genomic research in this species. Results: We report the Genoty…
To move or not to move: roles and specificity of plant RNA mobility
2020
Intercellular communication in plants coordinates cellular functions during growth and development, and in response to environmental cues. RNAs figure prominently among the mobile signaling molecules used. Many hundreds of RNA species move over short and long distances, and can be mutually exchanged in biotic interactions. Understanding the specificity determinants of RNA mobility and the physiological relevance of this phenomenon are areas of active research. Here, we highlight the recent progress in our knowledge of small RNA and messenger RNA movement. Particular emphasis is given to novel insight into the specificity determinants of messenger RNA mobility, the role of small RNA movement…
Melatonin in the seasonal response of the aphid Acyrthosiphon pisum.
2018
Aphids display life cycles largely determined by the photoperiod. During the warm long-day seasons, most aphid species reproduce by viviparous parthenogenesis. The shortening of the photoperiod in autumn induces a switch to sexual reproduction. Males and sexual females mate to produce overwintering resistant eggs. In addition to this full life cycle (holocycle), there are anholocyclic lineages that do not respond to changes in photoperiod and reproduce continuously by parthenogenesis. The molecular or hormonal events that trigger the seasonal response (i.e., induction of the sexual phenotypes) are still unknown. Although circadian synthesis of melatonin is known to play a key role in verteb…
How water-soluble chlorophyll protein extracts chlorophyll from membranes.
2020
Water-soluble chlorophyll proteins (WSCPs) found in Brassicaceae are non-photosynthetic proteins that bind only a small number of chlorophylls. Their biological function remains unclear, but recent data indicate that WSCPs are involved in stress response and pathogen defense as producers of reactive oxygen species and/or Chl-regulated protease inhibitors. For those functions, WSCP apoprotein supposedly binds Chl to become physiologically active or inactive, respectively. Thus, Chl-binding seems to be a pivotal step for the biological function of WSCP. WSCP can extract Chl from the thylakoid membrane but little is known about the mechanism of how Chl is sequestered from the membrane into the…
Synthetic conversion of leaf chloroplasts into carotenoid-rich plastids reveals mechanistic basis of natural chromoplast development
2020
Plastids, the defining organelles of plant cells, undergo physiological and morphological changes to fulfill distinct biological functions. In particular, the differentiation of chloroplasts into chromoplasts results in an enhanced storage capacity for carotenoids with industrial and nutritional value such as beta-carotene (provitamin A). Here, we show that synthetically inducing a burst in the production of phytoene, the first committed intermediate of the carotenoid pathway, elicits an artificial chloroplast-to-chromoplast differentiation in leaves. Phytoene overproduction initially interferes with photosynthesis, acting as a metabolic threshold switch mechanism that weakens chloroplast i…
Chloroplast genomes of Rubiaceae: Comparative genomics and molecular phylogeny in subfamily Ixoroideae.
2020
In Rubiaceae phylogenetics, the number of markers often proved a limitation with authors failing to provide well-supported trees at tribal and generic levels. A robust phylogeny is a prerequisite to study the evolutionary patterns of traits at different taxonomic levels. Advances in next-generation sequencing technologies have revolutionized biology by providing, at reduced cost, huge amounts of data for an increased number of species. Due to their highly conserved structure, generally recombination-free, and mostly uniparental inheritance, chloroplast DNA sequences have long been used as choice markers for plant phylogeny reconstruction. The main objectives of this study are: 1) to gain in…