Search results for "genes"

Gametic and somatic embryogenesis through in vitro anther culture of different Citrus genotypes

2015

Abstract: In vitro tissue culture represents a useful technique for advancing Citrus breeding and propagation. Among in vitro regeneration systems, anther culture is commonly used to produce haploids and doubled haploids for a fast-track producing homozygous lines, in comparison with the traditional self-pollination approach, which involves several generations of selfing. In addition, anthers culture can produce somatic embryos that can also be used for clonal propagation. In this study, two thermal shocks were applied to the anthers of six Citrus genotypes (two clementine and four sweet oranges), just after they were put in culture. The response obtained was different depending on the geno…

Interaction Between ABA Signaling and Copper Homeostasis inArabidopsis thaliana

2016

ABA is involved in plant responses to non-optimal environmental conditions, including nutrient availability. Since copper (Cu) is a very important micronutrient, unraveling how ABA affects Cu uptake and distribution is relevant to ensure adequate Cu nutrition in plants subjected to stress conditions. Inversely, knowledge about how the plant nutritional status can interfere with ABA biosynthesis and signaling mechanisms is necessary to optimize stress tolerance in horticultural crops. Here the reciprocal influence between ABA and Cu content was addressed by using knockout mutants and overexpressing transgenic plants of high affinity plasma membrane Cu transporters (pmCOPT) with altered Cu up…

Essentiality Is a Strong Determinant of Protein Rates of Evolution during Mutation Accumulation Experiments in Escherichia coli

2016

[EN] The Neutral Theory of Molecular Evolution is considered the most powerful theory to understand the evolutionary behavior of proteins. One of the main predictions of this theory is that essential proteins should evolve slower than dispensable ones owing to increased selective constraints. Comparison of genomes of different species, however, has revealed only small differences between the rates of evolution ofessential and nonessential proteins. In some analyses, these differences vanish once confounding factors are controlled for, whereas in other cases essentiality seems to have an independent, albeit small, effect. It has been argued that comparing relatively distant genomes may entai…

Climate Change Genomics Calls for Standardized Data Reporting

2020

The advent of new and affordable high-throughput sequencing techniques allows for the investigation of the genetic basis of environmental adaptation throughout the plant and animal kingdom. The framework of genotype-environment associations (GEA) provides a powerful link by correlating the geographic distribution of genotype patterns of individuals or populations with environmental factors on a spatial scale. We coarsely review the short history of GEA studies, summarizing available studies, organisms, data type, and data availability for these studies. GEA is a powerful tool in climate change research and we therefore focus on climate variables as environmental factors. While our initial a…

Carex sect. Rhynchocystis (Cyperaceae): a Miocene subtropical relict in the Western Palaearctic showing a dispersal‐derived Rand Flora pattern

2017

Aim To evaluate how Cenozoic climate changes shaped the evolution and distribution of Carex section Rhynchocystis. Location Western Palaearctic and Afrotropical regions (Rand Flora pattern). Methods DNA regions ITS, ETS (nuclear), matK and rpl32-trnLUAG (plastid) were amplified for 86 samples of species from section Rhynchocystis. Phylogenetic and phylogeographical relationships were inferred using maximum parsimony, Bayesian inference and coalescent-based species tree approaches. Divergence times and ancestral areas were also inferred. Results Carex section Rhynchocystis is a clade that diversified during the middle Miocene in Europe. Most cladogenesis events date to the middle and late Mi…

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…

What is Vipp1 good for?

2018

While Vipp1 (also known as IM30) clearly is essential for proper biogenesis of thylakoid membranes in chloroplasts and cyanobacteria, the exact function of Vipp1/IM30 still remains unclear. The recent in vivo study of Gutu et al. now demonstrates that Vipp1/IM30 forms localized puncta specifically at highly curved membrane regions at the cell periphery. These Vipp1/IM30 puncta were found being highly dynamic under normal growth conditions, while it has recently been shown that they stably associate with membranes under high-light conditions. These observations, together with the observation that other Vipp1/IM30 homologous proteins also form puncta under stress conditions, indicate a protec…

2019

The inner membrane-associated protein of 30 kDa (IM30, also known as Vipp1) is required for thylakoid membrane biogenesis and maintenance in cyanobacteria and chloroplasts. The protein forms large rings of ∼2 MDa and triggers membrane fusion in presence of Mg2+. Based on the here presented observations, IM30 rings are built from dimers of dimers, and formation of these tetrameric building blocks is driven by interactions of the central coiled-coil, formed by helices 2 and 3, and stabilized via additional interactions mainly involving helix 1. Furthermore, helix 1 as well as C-terminal regions of IM30 together negatively regulate ring-ring contacts. We propose that IM30 rings represent the i…

Evaluation of chloroplast genome annotation tools and application to analysis of the evolution of coffee species.

2018

International audience; Chloroplast sequences are widely used for phylogenetic analysis due to their high degree of conservation in plants. Whole chloroplast genomes can now be readily obtained for plant species using new sequencing methods, giving invaluable data for plant evolution However new annotation methods are required for the efficient analysis of this data to deliver high quality phylogenetic analyses. In this study, the two main tools for chloroplast genome annotation were compared. More consistent detection and annotation of genes were produced with GeSeq when compared to the currently used Dogma. This suggests that the annotation of most of the previously annotated chloroplast …

Microspore Embryogenesis Through Anther Culture in Citrus clementina Hort. ex Tan.

2016

Anther culture is a biotechnological method that allows to obtain, in one step, homozygous plants, very important to plant breeding, due to their numerous applications in mutation research, selection, genome sequencing, genetic analysis, and transformation. To induce the microspores, i.e., the immature male gametes, to switch from the normal gametophytic pathway to the sporophytic one, it is necessary to submit them to a type of stress, such as high or low temperature, starvation, or magnetic field. Stress can be applied to the donor plants and/or the fl oral buds or the anthers or the isolated microspores, before or during the culture. In this chapter, the protocol to induce gametic embryo…