plant cell genetics
13.5K views | +0 today
Follow
 
Scooped by Jean-Pierre Zryd
onto plant cell genetics
Scoop.it!

Dramatic genotypic difference in, and effect of genetic crossing on, tissue culture-induced mobility of retrotransposon Tos17 in rice - Springer

Dramatic genotypic difference in, and effect of genetic crossing on, tissue culture-induced mobility of retrotransposon Tos17 in rice - Springer | plant cell genetics | Scoop.it

We show for the first time that intraspecific crossing may impact mobility of the prominent endogenous retrotransposon Tos17 under tissue culture conditions in rice.
Abstract
Tos17, an endogenous copia retrotransposon of rice, is transpositionally active in tissue culture. To study whether there exists fundamental genotypic difference in the tissue culture-induced mobility of Tos17, and if so, whether the difference is under genetic and/or epigenetic control, we conducted this investigation. We show that dramatic difference in tissue culture-induced Tos17 mobility exists among different rice pure-line cultivars sharing the same maternal parent: of the three lines studied that harbor Tos17, two showed mobilization of Tos17, which accrued in proportion to subculture duration, while the third line showed total quiescence (immobility) of the element and the fourth line did not contain the element. In reciprocal F1 hybrids between Tos17-mobile and -immobile (or absence) parental lines, immobility was dominant over mobility. In reciprocal F1 hybrids between both Tos17-mobile parental lines, an additive or synergistic effect on mobility of the element was noticed. In both types of reciprocal F1 hybrids, clear difference in the extent of Tos17 mobility was noted between crossing directions. Given that all lines share the same maternal parent, this observation indicates the existence of epigenetic parent-of-origin effect. We conclude that the tissue culture-induced mobility of Tos17 in rice is under complex genetic and epigenetic control, which can be either enhanced or repressed by intraspecific genetic crossing.

more...
No comment yet.
plant cell genetics
Your new post is loading...
Your new post is loading...
Rescooped by Jean-Pierre Zryd from SEED DEV LAB Biblio
Scoop.it!

Plant glandular trichomes: natural cell factories of high biotechnological interest

Plant glandular trichomes: natural cell factories of high biotechnological interest | plant cell genetics | Scoop.it
Empty description

Via Loïc Lepiniec
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

A transgenic strategy for controlling plant bugs (Adelphocoris suturalis) through expression of double‐stranded RNA homologous to fatty acyl‐coenzyme A reductase in cotton

A transgenic strategy for controlling plant bugs (Adelphocoris suturalis) through expression of double‐stranded RNA homologous to fatty acyl‐coenzyme A reductase in cotton | plant cell genetics | Scoop.it
Plant bugs (Miridae species), which are sap-sucking insects, have emerged as major pests of cotton in China. Most Miridae species are not sensitive to commercial Bacillus thuringiensis (Bt) cotton, resulting in significant economic losses and an increased application of insecticide, which eventually may compromise the future of Bt cotton.
We demonstrate that FATTY ACYL-COA REDUCTASE (AsFAR) plays an essential role in the reproduction of the bug Adelphocoris suturalis. Down-regulation of AsFAR expression by injection of double-stranded RNA suppresses ovarian development and female fertility, resulting in females producing few viable offspring.
To determine the viability of an RNA interference approach to limit FAR expression and reproductive ability in A. suturalis, a dsRNA targeting the AsFAR gene (dsAsFAR) of A. suturalis was expressed in transgenic cotton plants. AsFAR transcription levels were significantly downregulated in A. suturalis feeding on the transgenic plants. In contained field trials, the transgenic cotton lines significantly suppressed the development of A. suturalis populations and were resistant to damage caused by plant bug infestation.
These results suggest a new strategy for the management of plant bug pests of cotton.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Nicotine in floral nectar pharmacologically influences bumblebee learning of floral features

Nicotine in floral nectar pharmacologically influences bumblebee learning of floral features | plant cell genetics | Scoop.it

Many plants defend themselves against herbivores by chemical deterrents in their tissues and the presence of such substances in floral nectar means that pollinators often encounter them when foraging. The effect of such substances on the foraging behaviour of pollinators is poorly understood. Using artificial flowers in tightly-controlled laboratory settings, we examined the effects of the alkaloid nicotine on bumblebee foraging performance. We found that bumblebees confronted simultaneously with two equally rewarded nicotine-containing and nicotine-free flower types are deterred only by unnaturally high nicotine concentrations. This deterrence disappears or even turns into attraction at lower nectar-relevant concentrations. The alkaloid has profound effects on learning in a dose-dependent manner. At a high natural dose, bees learn the colour of a nicotine-containing flower type more swiftly than a flower type with the same caloric value but without nicotine. Furthermore, after experiencing flowers containing nicotine in any tested concentration, increasing numbers of bumblebees stay more faithful to these flowers, even if they become a suboptimal choice in terms of reward. These results demonstrate that alkaloids enhance pollinator flower constancy, opening new perspectives in co-evolutionary process between plants and pollinators.

more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Evolutionary forces affecting synonymous variations in plant genomes

Evolutionary forces affecting synonymous variations in plant genomes | plant cell genetics | Scoop.it
Author summary In protein coding genes, base composition strongly varies within and among plant genomes, especially at positions where changes do not alter the coded protein (synonymous variations). Some species, such as the model plant Arabidopsis thaliana, are relatively GC-poor and homogeneous while others, such as grasses, are highly heterogeneous and GC-rich. The causes of these variations are still debated: are they mainly due to selective or neutral processes? Answering to this question is important to correctly infer whether variations in base composition may have functional roles or not. We extended a population genetics method to jointly estimate the different forces that may affect synonymous variations and applied it to genomic datasets in 11 flowering plant species. We found that GC-biased gene conversion, a neutral process associated with recombination that mimics selection by favouring G and C bases, is a widespread and stronger process than selection and that it could explain the large variation in base composition observed in plant genomes. Our results bear implications for analysing plant genomes and for correctly interpreting what could be functional or not.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Advances in the MYB–bHLH–WD Repeat (MBW) Pigment Regulatory Model: Addition of a WRKY Factor and Co-option of an Anthocyanin MYB for Betalain Regulation | Plant and Cell Physiology | Oxford Academic

Advances in the MYB–bHLH–WD Repeat (MBW) Pigment Regulatory Model: Addition of a WRKY Factor and Co-option of an Anthocyanin MYB for Betalain Regulation | Plant and Cell Physiology | Oxford Academic | plant cell genetics | Scoop.it
Flavonoids are secondary metabolites derived from the general phenylpropanoid pathway and are widespread throughout the plant kingdom. The functions of flavonoids are diverse, including defense against phytopathogens, protection against UV light damage and oxidative stress, regulation of auxin transport and allelopathy. One of the most conspicuous functions of flavonoids has long attracted the attention of pollinators and scientist alike: the vivid shades of red, pink, orange, blue and purple on display in the flowers of angiosperms. Thus, flavonoid pigments have perhaps been the most intensely studied phenylpropanoids. From Mendel to McClintock and up to the present, studies centered on flavonoid pigments have resulted in some of the most important scientific discoveries of the last 150 years, including the first examples of transcriptional regulation in plants. Here we focus on the highly conserved MYB–bHLH–WD repeat (MBW) transcriptional complex model for the regulation of the flavonoid pigment pathway. We will survey the history of the MBW model spanning the last three decades, highlighting the major findings that have contributed to our current understanding. In particular, recent discoveries regarding WRKY protein control of the flavonoid pigment pathway and its relationship to the MBW complex will be emphasized. In addition, we will discuss recent findings about the regulation of the beet betalain pigment pathway, and how a MYB member of the MBW complex was co-opted to regulate this chemically unrelated but functionally equivalent pathway.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Towards mastering CRISPR-induced gene knock-in in plants: Survey of key features and focus on the model Physcomitrella patens

Towards mastering CRISPR-induced gene knock-in in plants: Survey of key features and focus on the model Physcomitrella patens | plant cell genetics | Scoop.it
Beyond its predominant role in human and animal therapy, the CRISPR-Cas9 system has also become an essential tool for plant research and plant breeding. Agronomic applications rely on the mastery of gene inactivation and gene modification. However, if the knock-out of genes by non-homologous end-joining (NHEJ)-mediated repair of the targeted double-strand breaks (DSBs) induced by the CRISPR-Cas9 system is rather well mastered, the knock-in of genes by homology-driven repair or end-joining remains difficult to perform efficiently in higher plants. In this review, we describe the different approaches that can be tested to improve the efficiency of CRISPR–induced gene modification in plants, which include the use of optimal transformation and regeneration protocols, the design of appropriate guide RNAs and donor templates and the choice of nucleases and means of delivery. We also present what can be done to orient DNA repair pathways in the target cells, and we show how the moss Physcomitrella patens can be used as a model plant to better understand what DNA repair mechanisms are involved, and how this knowledge could eventually be used to define more performant strategies of CRISPR-induced gene knock-in.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

CRISPR, microbes and more are joining the war against crop killers

CRISPR, microbes and more are joining the war against crop killers | plant cell genetics | Scoop.it

Agricultural scientists look beyond synthetic chemistry to battle pesticide resistance.


Resistance to conventional pesticides — among insects, weeds or microbial pathogens — is common on farms worldwide. CropLife International, an industry association based in Brussels, supports efforts that have counted 586 arthropod species, 235 fungi and 252 weeds with resistance to at least one synthetic pesticide (see 'The rise of resistance'). And that's just the cases that scientists have formally identified and recorded.

more...
No comment yet.
Rescooped by Jean-Pierre Zryd from Fragments of Science
Scoop.it!

Newton's journal reveals seeds of plant biology

Newton's journal reveals seeds of plant biology | plant cell genetics | Scoop.it
Sir Isaac Newton's interest in botany extended well beyond the fabled apple falling from a tree - he also appears to have understood how water moves from roots to leaves over 200 years before botanists did.

Via Mariaschnee
more...
No comment yet.
Rescooped by Jean-Pierre Zryd from Plant and Seed Biology
Scoop.it!

Rice plant engineered with a ‘tunable’ immune system could fight multiple diseases at once

Rice plant engineered with a ‘tunable’ immune system could fight multiple diseases at once | plant cell genetics | Scoop.it
Farmers are constantly spraying pesticides on their crops to combat an array of viral, bacterial, and fungal invaders. Scientists have been trying to get around these chemicals for years by genetically engineering hardy plants resilient to the array of diseases caused by microbial beasties. Most attempts so far confer protection against a single disease, but now researchers have developed a rice plant that fights multiple pathogens at once—without loss to the crop yield—by hooking up a tunable amplifier to the plant’s immune system.

Via Loïc Lepiniec
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Towards mastering CRISPR-induced gene knock-in in plants: survey of key features and focus on the model Physcomitrella patens

Towards mastering CRISPR-induced gene knock-in in plants: survey of key features and focus on the model Physcomitrella patens | plant cell genetics | Scoop.it
Beyond its predominant role in human and animal therapy, the CRISPR-Cas9 system has also become an essential tool for plant research and plant breeding. Agronomic applications rely on the mastery of gene inactivation and gene modification. However, if the knock-out of genes by non-homologous end-joining (NHEJ)-mediated repair of the targeted double-strand breaks (DSBs) induced by the CRISPR-Cas9 system is rather well mastered, the knock-in of genes by homology-driven repair or end-joining remains difficult to perform efficiently in higher plants. In this review, we describe the different approaches that can be tested to improve the efficiency of CRISPR–induced gene modification in plants, which include the use of optimal transformation and regeneration protocols, the design of appropriate guide RNAs and donor templates and the choice of nucleases and means of delivery. We also present what can be done to orient DNA repair pathways in the target cells, and we show how the moss Physcomitrella patens can be used as a model plant to better understand what DNA repair mechanisms are involved, and how this knowledge could eventually be used to define more performant strategies of CRISPR-induced gene knock-in.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Quantitative Proteomics Analysis of Developmental Reprogramming in Protoplasts of the Moss Physcomitrella patens | Plant and Cell Physiology | Oxford Academic

Quantitative Proteomics Analysis of Developmental Reprogramming in Protoplasts of the Moss Physcomitrella patens | Plant and Cell Physiology | Oxford Academic | plant cell genetics | Scoop.it
The moss Physcomitrella patens is a model system for studying Plant developmental processes. To better understand the biochemical and physiological changes involved in developmental reprogramming, we conducted a quantitative proteomics analysis for protonemata, protoplasts made therefrom and protoplasts regenerated for 2 d. Using an iTRAQ peptide labeling strategy and liquid chromatography–tandem mass spectrometry (LC-MS/MS), >3,000 peptides and 1,000 proteins were quantified. Of these, 162 proteins were identified as having differential abundances during developmental reprogramming. These proteins were involved in various biological functions, such as defense, energy production, translation, metabolism, protein destination and storage, transcription, transport, cell growth/division, cell structure and signal transduction. Of these, the proteins involved in energy production and translation increased in abundance, while many of the metabolism and defense proteins decreased in abundance. In addition, most of the cell growth/division, protein stability and cell structure proteins were also down-regulated. This is the first report on the metabolic changes involved in developmental reprogramming in protoplasts. The significance of metabolic networks in developmental programming is beginning to emerge. Our study suggested that stress signals, energy metabolism and ribosomal proteins are pivotal components during developmental programming.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Rapid breeding of parthenocarpic tomato plants using CRISPR/Cas9

Rapid breeding of parthenocarpic tomato plants using CRISPR/Cas9 | plant cell genetics | Scoop.it
Parthenocarpy in horticultural crop plants is an important trait with agricultural value for various industrial purposes as well as direct eating quality. Here, we demonstrate a breeding strategy to generate parthenocarpic tomato plants using the CRISPR/Cas9 system. We optimized the CRISPR/Cas9 system to introduce somatic mutations effectively into SlIAA9—a key gene controlling parthenocarpy—with mutation rates of up to 100% in the T0 generation. Furthermore, analysis of off-target mutations using deep sequencing indicated that our customized gRNAs induced no additional mutations in the host genome. Regenerated mutants exhibited morphological changes in leaf shape and seedless fruit—a characteristic of parthenocarpic tomato. And the segregated next generation (T1) also showed a severe phenotype associated with the homozygous mutated genome. The system developed here could be applied to produce parthenocarpic tomato in a wide variety of cultivars, as well as other major horticultural crops, using this precise and rapid breeding technique.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Crossing kingdoms: Using decellularized plants as perfusable tissue engineering scaffolds

Crossing kingdoms: Using decellularized plants as perfusable tissue engineering scaffolds | plant cell genetics | Scoop.it
Despite significant advances in the fabrication of bioengineered scaffolds for tissue engineering, delivery of nutrients in complex engineered human tissues remains a challenge. By taking advantage of the similarities in the vascular structure of plant and animal tissues, we developed decellularized plant tissue as a prevascularized scaffold for tissue engineering applications. Perfusion-based decellularization was modified for different plant species, providing different geometries of scaffolding. After decellularization, plant scaffolds remained patent and able to transport microparticles. Plant scaffolds were recellularized with human endothelial cells that colonized the inner surfaces of plant vasculature. Human mesenchymal stem cells and human pluripotent stem cell derived cardiomyocytes adhered to the outer surfaces of plant scaffolds. Cardiomyocytes demonstrated contractile function and calcium handling capabilities over the course of 21 days. These data demonstrate the potential of decellularized plants as scaffolds for tissue engineering, which could ultimately provide a cost-efficient, “green” technology for regenerating large volume vascularized tissue mass.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Synthetic Botany

Plants are attractive platforms for synthetic biology and metabolic engineering. Plants’ modular and plastic body plans, capacity for photosynthesis, extensive secondary metabolism, and agronomic systems for large-scale production make them ideal targets for genetic reprogramming. However, efforts in this area have been constrained by slow growth, long life cycles, the requirement for specialized facilities, a paucity of efficient tools for genetic manipulation, and the complexity of multicellularity. There is a need for better experimental and theoretical frameworks to understand the way genetic networks, cellular populations, and tissue-wide physical processes interact at different scales. We highlight new approaches to the DNA-based manipulation of plants and the use of advanced quantitative imaging techniques in simple plant models such as Marchantia polymorpha. These offer the prospects of improved understanding of plant dynamics and new approaches to rational engineering of plant traits.

more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Non-model model organisms

Non-model model organisms | plant cell genetics | Scoop.it
Model organisms are widely used in research as accessible and convenient systems to study a particular area or question in biology. Traditionally only a handful of organisms have been widely studied, but modern research tools are enabling researchers to extend the set of model organisms to include less-studied and more unusual systems. This Forum highlights a range of 'non-model model organisms' as emerging systems for tackling questions across the whole spectrum of biology (and beyond), the opportunities and challenges, and the outlook for the future.
more...
No comment yet.
Rescooped by Jean-Pierre Zryd from Ag Biotech News
Scoop.it!

Genetically modified sugarcane developed by CTC in Brazil is approved at CTNBio - Unica (2017) 

The new variety is resistant to sugarcane borer, the main pest that affects the crops in Brazil, generating losses that reach R$ 5 billion per year. 


The ... CTNBio (National Biosafety Technical Commission) has approved the commercial use of the first genetically-modified sugarcane (Bt Sugarcane) developed by the Brazilian sugarcane breeding and technology company... CTC. The Bt Sugarcane variety was submitted to CTNBio, which considered the safety of the biotechnology-derived variety for the environment and human and animal health. This is the first genetically-modified sugarcane approved for marketing in the world.

The new variety, CTC 20 BT, is resistant to crop damage caused by the main sugarcane pest in Brazil, the sugarcane borer. According to a survey carried out by agricultural experts, damage caused by the sugarcane borer results in approximately R$ 5 billion per year, due to losses in sugarcane yield and quality, lower grower insecticide use and costs, and impacts on processors of sugar and ethanol. The helpful Bt gene (Bacillus thuringiensis), found in CTC 20 BT, has been used widely in both Brazilian and global agriculture for over 20 years in biotechnology-derived crops like soybean, maize, cotton, among others. 


“The Bt Sugarcane approval by CTNBio is a great achievement by CTC and the national sugar-ethanol sector”... In the next years, we plan to expand the portfolio of varieties resistant to the borer, adapted to each of the producing regions of Brazil. Further, CTC plans to develop other varieties that are resistant to other insect pests and also tolerant to herbicides... in addition to the economic gains from CTC 20 BT, producers can both simplify their logistics and improve their operation’s environmental management.”

The extensive scientific dossier, which evaluated the genetically-modified sugarcane (GM), was submitted to CTNBio at the end of 2015 for the assessment of health and environmental safety using internationally-accepted standards. Processing studies proved that the sugar and ethanol obtained from the new variety are identical to those products derived from conventional sugarcane. Studies additionally showed that both the Bt gene and protein found in CTC 20 BT sugarcane are completely eliminated from sugarcane derivatives during the manufacturing process. Further, environmental studies did not find any negative effects on soil composition, sugarcane biodegradability, or insect populations, with the exception of the target pests (mainly the borer)... 

CTC will work closely with producers, starting with CTC 20 BT seedling distribution and followed by closely-monitored field planting... “The seedling propagation process will proceed like any conventional new variety introduction, with a planted area growth rate that increases gradually, as new plants are replanted to expand cultivated area and not used in sugar production. This process is aligned with the schedule for obtaining international approvals for the sugar produced from the GM sugarcane”... 


http://english.unica.com.br/news/16900437920334804993/genetically-modified-sugarcane-developed-by-ctc-in-brazil-is-approved-at-ctnbio



Via Alexander J. Stein
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Low Rate of Somatic Mutations in a Long-Lived Oak Tree (L'Arbre de Napoléon UNIL)

Low Rate of Somatic Mutations in a Long-Lived Oak Tree (L'Arbre de Napoléon UNIL) | plant cell genetics | Scoop.it


Because plants do not possess a proper germline, deleterious mutations that occur in the soma can be passed to gametes. It has generally been assumed that the large number of somatic cell divisions separating zygote from gamete formation in long-lived plants should lead to many mutations. However, a recent study showed that surprisingly few cell divisions separate apical stem cells from axillary stem cells in annual plants, challenging this view. To test this prediction, we generated and analysed the full genome sequence of two terminal branches of a 234-year-old oak tree and found very few fixed somatic single-nucleotide variants (SNVs), whose sequential appearance in the tree could reliably be traced back along nested sectors of younger branches. Our data indicate that the stem cells of shoot meristems in trees are robustly protected from accumulation of mutations, analogous to the germline in animals.


https://fr.wikipedia.org/wiki/Ch%C3%AAne_de_Napol%C3%A9on

more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Cells reprogramming to stem cells inhibit the reprogramming of adjacent cells in the moss Physcomitrella patens

Cells reprogramming to stem cells inhibit the reprogramming of adjacent cells in the moss Physcomitrella patens | plant cell genetics | Scoop.it
Under certain circumstances differentiated cells can be reprogrammed to form stem cells in land plants, but only a portion of the cells reprograms successfully. A long-distance inhibitory signal from reprogrammed cells to surrounding cells has been reported in some ferns. Here we show the existence of anisotropic inhibitory signal to regulate stem cell formation in the moss Physcomitrella patens. When single cells were isolated from a gametophore leaf, over 90% of them were reprogrammed to stem cells with characteristic nuclear expansion. By contrast, when two adjacent cells were isolated, the nuclei of both cells expanded, but successful reprogramming of both cells occurred only in approximately one fifth of the pairs. When three aligned cells were isolated, the reprogramming rate of both edge cells decreased with a living middle cell but did not with a dead middle cell. Furthermore, unequal conversion into stem cells was more prominent in cell pairs aligned parallel to the proximal-distal leaf axis than in those perpendicular to the axis. This study gives an insight into the role of the inhibitory signal in development and evolution as well as the efficient stem cell induction from differentiated cells.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Cytosolic and Nuclear Co-localization of Betalain Biosynthetic Enzymes in Tobacco Suggests that Betalains Are Synthesized in the Cytoplasm and/or Nucleus of Betalainic Plant Cells | Pla...

Cytosolic and Nuclear Co-localization of Betalain Biosynthetic Enzymes in Tobacco Suggests that Betalains Are Synthesized in the Cytoplasm and/or Nucleus of Betalainic Plant Cells | Pla... | plant cell genetics | Scoop.it
Betalains replace anthocyanins as color pigments in most families of Caryophyllales. Unlike anthocyanins, betalains are derived from tyrosine via three enzymatic steps: hydroxylation of L-tyrosine to L-3,4-dihydroxyphenylalanine (L-DOPA; step 1), and conversion of L-DOPA to betalamic acid (step 2), and to cyclo-DOPA (cDOPA; step 3). The principal enzymes responsible for these reactions have been elucidated at the molecular level, but their subcellular localizations have not been explored; hence, the intracellular compartments wherein betalains are biosynthesized remain unknown. Here, we report on the subcellular localization of these principal enzymes. Bioinformatic predictors and N- and C-terminal GFP tagging in transgenic tobacco, showed that Beta vulgaris CYP76AD1 which mediates both steps 1 and 3, DODA1 that catalyzes step 2, and CYP76AD6 which also mediates step 1, were similarly localized to the cytoplasm and nucleus (although the P450s were also weakly present in the endoplasmic reticulum). These two compartments were also the principal locations of Mirabilis jalapa cDOPA5GT. The cytoplasmic and nuclear co-localization of these key enzymes in tobacco suggests that betalains are biosynthesized in the cytoplasm and/or nucleus of betalain-containing plant cells. Elucidation of the subcellular compartmentation of betalain biosynthesis will facilitate the bioengineering of the betalain biosynthetic pathway in non-betalain-containing plants.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

New alleles of the wheat domestication gene Q reveal multiple roles in growth and reproductive development

New alleles of the wheat domestication gene Q reveal multiple roles in growth and reproductive development | plant cell genetics | Scoop.it
The advantages of free threshing in wheat led to the selection of the domesticated Q allele, which is now present in almost all modern wheat varieties. Q and the pre-domestication allele, q, encode an AP2 transcription factor, with the domesticated allele conferring a free-threshing character and a subcompact (i.e. partially compact) inflorescence (spike). We demonstrate that mutations in the miR172 binding site of the Q gene are sufficient to increase transcript levels via a reduction in miRNA-dependent degradation, consistent with the conclusion that a single nucleotide polymorphism in the miRNA binding site of Q relative to q was essential in defining the modern Q allele. We describe novel gain- and loss-of-function alleles of Q and use these to define new roles for this gene in spike development. Q is required for the suppression of ‘sham ramification’, and increased Q expression can lead to the formation of ectopic florets and spikelets (specialized inflorescence branches that bear florets and grains), resulting in a deviation from the canonical spike and spikelet structures of domesticated wheat.
more...
No comment yet.
Rescooped by Jean-Pierre Zryd from MycorWeb Plant-Microbe Interactions
Scoop.it!

Plant biology: An immunity boost combats crop disease : Nature

Plant biology: An immunity boost combats crop disease : Nature | plant cell genetics | Scoop.it
Xu and colleagues provide insight into how features of the 5′ region of the TBF1 mRNA mediate its translational control. In this region, there are two previously identified10 short upstream open reading frames (uORFs), sequences that encode short peptides and precede the start of the open reading frame (ORF) that encodes TBF1. The authors identified another feature of interest in this 5′ region — a short adenine-rich nucleotide sequence located just before the two uORFs (Fig. 1). Adenine is a nucleotide known as a purine, and because purines are often designated by the letter 'R', the authors named this sequence the R-motif. They found that, in the absence of pathogen challenge, the uORFs strongly inhibit the ability of the ribosome protein-synthesis machinery to translate the TBF1-encoding ORF located downstream in the mRNA. The R-motif adds to this translational control. When plants were treated with elf18, the authors found that this repression of TBF1 synthesis was rapidly and transiently reversed.

Via Francis Martin
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

Ultrastructural study on the interaction between Physcomitrella patens and Botrytis cinerea - Yan - Plant Pathology - Wiley Online Library

Ultrastructural study on the interaction between Physcomitrella patens and Botrytis cinerea - Yan - Plant Pathology - Wiley Online Library | plant cell genetics | Scoop.it
Little is known about the interactions of bryophytes with their pathogens compared with those of flowering plants. We used the moss Physcomitrella patens and fungal pathogen Botrytis cinerea to investigate their interaction at the ultrastructural level. Infection behaviors of B. cinerea in moss tissues were observed during 1–7 d after inoculation. Some appressoria directly penetrated P. patens cytoplasm through leaf cell walls, and others entered the intercellular spaces of leaves and infected cytoplasm. Infection hyphae were observed in sclerenchyma cells of P. patens stems for the first time. Our results demonstrated that the ratio of hyphae-inoculated leaf cells to leaf numbers could be used to quantify the disease development process at 24 h after inoculation. Our ultrastructural studies revealed two responses of P. patens to B. cinerea inoculation: reinforcement of cell walls, including papillae formation; and cell death. This was the first observation of papillae for P. patens–B. cinerea interaction at the ultrastructural level. Papillae in P. Patens had a similar ultrastructure to those of higher plants, and may be involved in the defense response to B. cinerea infection. Thus papillae formation is likely an evolutionarily conserved defense mechanism from the early land colonization by plants. Cell death during the P. patens–B. cinerea interaction had some features of programmed cell death, with hydrogen peroxide produced in cytoplasm membranes, suggesting something like hypersensitive response. These ultrastructural studies suggested that P. patens could be a useful system for studying phytopathogens and to provide theoretical bases for defense mechanisms in evolutionary development.
more...
No comment yet.
Rescooped by Jean-Pierre Zryd from Agricultural Biodiversity
Scoop.it!

Golden Genes: The Movie

The frozen, bodiless genes of millions of plants, animals and humans are stored in biobanks around the world. They rekindle dreams of old: re-creating extinct species, ending world hunger, human life without illness or disease. But biobanks do more than
Via Luigi Guarino
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

A study of allelic diversity underlying flowering-time adaptation in maize landraces : Nature Genetics : Nature Research

A study of allelic diversity underlying flowering-time adaptation in maize landraces : Nature Genetics : Nature Research | plant cell genetics | Scoop.it
Landraces (traditional varieties) of domesticated species preserve useful genetic variation, yet they remain untapped due to the genetic linkage between the few useful alleles and hundreds of undesirable alleles1. We integrated two approaches to characterize the diversity of 4,471 maize landraces. First, we mapped genomic regions controlling latitudinal and altitudinal adaptation and identified 1,498 genes. Second, we used F-one association mapping (FOAM) to map the genes that control flowering time, across 22 environments, and identified 1,005 genes. In total, we found that 61.4% of the single-nucleotide polymorphisms (SNPs) associated with altitude were also associated with flowering time. More than half of the SNPs associated with altitude were within large structural variants (inversions, centromeres and pericentromeric regions). The combined mapping results indicate that although floral regulatory network genes contribute substantially to field variation, over 90% of the contributing genes probably have indirect effects. Our dual strategy can be used to harness the landrace diversity of plants and animals.
more...
No comment yet.
Scooped by Jean-Pierre Zryd
Scoop.it!

I Have a Dream: Organic Movements Include Gene Manipulation to Improve Sustainable Farming

I Have a Dream: Organic Movements Include Gene Manipulation to Improve Sustainable Farming | plant cell genetics | Scoop.it
Abstract: Several papers in a Special Issue of Sustainability have recently discussed various aspects to evaluate whether organic farming and gene manipulation are compatible. A special emphasis was given to new plant breeding techniques (NPBTs). These new approaches allow the most predictable genetic alterations of crop plants in ways that the genetically modified plant is identical to a plant generated by conventional breeding. The articles of the Special Issue present the arguments pro and contra the inclusion of the plants generated by NPBTs in organic farming. Organic movements have not yet made a final decision whether some of these techniques should be accepted or banned. In my view these novel genetically manipulated (GM) crops could be used in such a way as to respect the requirements for genetically manipulated organisms (GMOs) formulated by the International Federation of Organic Movements (IFOAM). Reviewing the potential benefits of disease-resistant potatoes and bananas, it seems possible that these crops support organic farming. To this end, I propose specific requirements that the organic movements should proactively formulate as their standards to accept specific GM crops.
more...
No comment yet.