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Zeaxanthin Binds to Light-Harvesting Complex Stress-Related Protein to Enhance Nonphotochemical Quenching in Physcomitrella patens

Zeaxanthin Binds to Light-Harvesting Complex Stress-Related Protein to Enhance Nonphotochemical Quenching in Physcomitrella patens | plant cell genetics | Scoop.it

Nonphotochemical quenching (NPQ) dissipates excess energy to protect the photosynthetic apparatus from excess light. The moss Physcomitrella patens exhibits strong NPQ by both algal-type light-harvesting complex stress-related (LHCSR)–dependent and plant-type S subunit of Photosystem II (PSBS)-dependent mechanisms. In this work, we studied the dependence of NPQ reactions on zeaxanthin, which is synthesized under light stress by violaxanthin deepoxidase (VDE) from preexisting violaxanthin. We produced vde knockout (KO) plants and showed they underwent a dramatic reduction in thermal dissipation ability and enhanced photoinhibition in excess light conditions. Multiple mutants (vde lhcsr KO and vde psbs KO) showed that zeaxanthin had a major influence on LHCSR-dependent NPQ, in contrast with previous reports in Chlamydomonas reinhardtii. The PSBS-dependent component of quenching was less dependent on zeaxanthin, despite the near-complete violaxanthin to zeaxanthin exchange in LHC proteins. Consistent with this, we provide biochemical evidence that native LHCSR protein binds zeaxanthin upon excess light stress. These findings suggest that zeaxanthin played an important role in the adaptation of modern plants to the enhanced levels of oxygen and excess light intensity of land environments.

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Letter From The Editor: Rainbow Six and Golden Rice - Food Safety News (2013)

Letter From The Editor: Rainbow Six and Golden Rice - Food Safety News (2013) | plant cell genetics | Scoop.it

Labor Day Weekend is always good time for reading books and recent events on the other side of the world caused me to remember one of my favorite Tom Clancy novels... A smaller version of that plot, some would say much smaller, played out recently in the Philippines when scientific trials of “Golden Rice” were destroyed by eco-terrorists of a different stripe—those who oppose genetically modified organisms (GMOs).

 

There was no corporate involvement in this one, just government’s Philippine Research Institute and the International Rice Research Institute and other public sector partners working for humanity. The golden GMO in Golden Rice is vitamin A, which is intended to help overcome malnutrition in the third World. All stamped out in the name of food safety, of course...

 

Thankfully, the world of science and academia is rising up in the support of biotechnology on this one. Months of government-funded research and important data collection was compromised in this one.

 

Vitamin A deficiencies are not a big concern in the first world where eco-terrorists come from, usually before they move on to graduate school. But in the real world, about two million deaths and a half million cases of irreversible blindness are attributable to lack of Vitamin A. Most who suffer from Vitamin A deficiency are women and children, but who cares if you are feeling righteous about being you, right?

 

“As a toxicologist with 30 years of experience in food, cosmetics, pesticides and pharmaceuticals, I know the claims about risks of GM food are disingenuous and reflect a political rather than moral position,” writes Dr. Andrew Bartholomaeus, University of Canberra toxicology expert. “The lives of millions are at risk from the mindless actions of ill informed anti-biotech activists.”

 

“Golden Rice is a breakthrough in bioforication of natural plant products,” Australian National University biology lecturer Christopher Cazzonelli added. “I am a leading plant scientist and work on the regulation of carotenoid biosynthesis in plants. So please stop the destruction of field trials and help save lives.”

 

Dr Channapatna Prakash of Alabama’s Tuskegee University has launched an online petition urging Filipino politicians and policy makers to continue the vital research. They’ve gone over their goal of reaching 5,000 signatures since the Aug. 8 attack, but the more support they get will help persuade Filipino decision makers to continue the important work to field Golden Rice...

 


Via Alexander J. Stein
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Alexander J. Stein's curator insight, September 1, 2013 9:41 AM

For my taste the language of the editorial is too aggressive and hyped - and therefore fails to be constructive - but I dare say it may be a good indication that no food safety concerns are expected to arise from Golden Rice: Would the website of a law firm that specialises in food-related litigation come out so strongly in support of Golden Rice if there was reason to doubt its safety? Perhaps not, they'd probably have too much to lose and little to gain.  

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Trends in Genetics - Teosinte as a model system for population and ecological genomics

Trends in Genetics - Teosinte as a model system for population and ecological genomics | plant cell genetics | Scoop.it

Summary

As the cost of next-generation sequencing diminishes and genomic resources improve, crop wild relatives are well positioned to make major contributions to the field of ecological genomics via full-genome resequencing and reference-assisted de novo assembly of genomes of plants from natural populations. The wild relatives of maize, collectively known as teosinte, are a more varied and representative study system than many other model flowering plants. In this review of the population and ecological genomics of the teosintes we highlight recent advances in the study of maize domestication, introgressive hybridization, and local adaptation, and discuss future prospects for applying the genomic resources of maize to this intriguing group of species. The maize/teosinte study system is an excellent example of how crops and their wild relatives can bridge the model/non-model gap.


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Jorge Sáenz Mata's curator insight, March 6, 2013 6:48 PM

The teosinte are wild relatives of maize. 

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Terrestrial nitrogen–carbon cycle interactions at the global scale

Interactions between the terrestrial nitrogen (N) and carbon (C) cycles shape the response of ecosystems to global change. However, the global distribution of nitrogen availability and its importance in global biogeochemistry and biogeochemical interactions with the climate system remain                     uncertain. Based on projections of a terrestrial biosphere model scaling ecological understanding of nitrogen–carbon cycle interactions to global scales, anthropogenic nitrogen additions since 1860 are estimated to have enriched the terrestrial biosphere by 1.3 Pg N, supporting the sequestration of                     11.2 Pg C. Over the same time period, CO2 fertilization has increased terrestrial carbon storage by 134.0 Pg C, increasing the terrestrial nitrogen stock by 1.2 Pg N. In 2001–2010, terrestrial ecosystems sequestered an estimated total of 27 Tg N yr−1 (1.9 Pg C yr−1), of which 10 Tg N yr−1 (0.2 Pg C yr−1) are due to anthropogenic nitrogen deposition. Nitrogen availability already limits terrestrial carbon sequestration in the boreal and temperate zone, and will constrain future                     carbon sequestration in response to CO2 fertilization (regionally by up to 70% compared with an estimate without considering nitrogen–carbon interactions). This reduced terrestrial carbon uptake will probably dominate the role of the terrestrial nitrogen cycle in the climate system, as it accelerates the accumulation of anthropogenic CO2 in the atmosphere. However, increases of N2O emissions owing to anthropogenic nitrogen and climate change (at a rate of approx. 0.5 Tg N yr−1 per 1°C degree climate warming) will add an important long-term climate forcing.

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A novel EPSP-synthase transgene for glyphosate resistance stimulates growth and fecundity in weedy rice without herbicide

A novel EPSP-synthase transgene for glyphosate resistance stimulates growth and fecundity in weedy rice without herbicide | plant cell genetics | Scoop.it
Understanding evolutionary interactions among crops and weeds can facilitate effective weed management. For example, gene flow from crops to their wild or weedy relatives can lead to rapid evolution in recipient populations. In rice (Oryza sativa), transgenic herbicide resistance is expected to spread to conspecific weedy rice (Oryza sativa f. spontanea) via hybridization.Here, we studied fitness effects of transgenic over-expression of a native 5-enolpyruvoylshikimate-3-phosphate synthase (epsps) gene developed to confer glyphosate resistance in rice. Controlling for genetic background, we examined physiological traits and field performance of crop–weed hybrid lineages that segregated for the presence or absence of this novel epsps transgene.Surprisingly, we found that transgenic F2 crop–weed hybrids produced 48–125% more seeds per plant than nontransgenic controls in monoculture- and mixed-planting designs without glyphosate application. Transgenic plants also had greater EPSPS protein levels, tryptophan concentrations, photosynthetic rates, and per cent seed germination compared with nontransgenic controls.Our findings suggest that over-expression of a native rice epsps gene can lead to fitness advantages, even without exposure to glyphosate. We hypothesize that over-expressed epsps may be useful to breeders and, if deployed, could result in fitness benefits in weedy relatives following transgene introgression.
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Plant, Cell & Environment - Special Issue: Plant Computational Biology

Plant, Cell & Environment - Special Issue: Plant Computational Biology | plant cell genetics | Scoop.it

From Steve Long and Mark Stitt's editorial:

 

"For young readers from within biology and from disciplines like chemistry, physics, mathematics and informatics, we hope these reviews provide a picture of the advances and excitement in plant computational biology, and motivate them to acquire the skills to join in this advance.

 

While strong math and computation skills have long been at the core of training for the physical sciences, this is now becoming critical to advancement of plant biology. Scientists with this training are likely to make some of our most important future advances – as is indeed indicated in the articles here, both by the visionary pioneers and by the emerging leaders in applying advanced math and computational skills to questions of environmental plant sciences."


Via Mary Williams
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Peter Buckland's curator insight, August 6, 2013 9:55 AM

Editorial says it all - big up for Maths & Plants!

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PLOS ONE: Evaluation of Reference Genes for RT qPCR Analyses of Structure-Specific and Hormone Regulated Gene Expression in Physcomitrella patens Gametophytes

PLOS ONE: Evaluation of Reference Genes for RT qPCR Analyses of Structure-Specific and Hormone Regulated Gene Expression in Physcomitrella patens Gametophytes | plant cell genetics | Scoop.it

The use of the moss Physcomitrella patens as a model system to study plant development and physiology is rapidly expanding. The strategic position of P. patens within the green lineage between algae and vascular plants, the high efficiency with which transgenes are incorporated by homologous recombination, advantages associated with the haploid gametophyte representing the dominant phase of the P. patens life cycle, the simple structure of protonemata, leafy shoots and rhizoids that constitute the haploid gametophyte, as well as a readily accessible high-quality genome sequence make this moss a very attractive experimental system. The investigation of the genetic and hormonal control of P. patens development heavily depends on the analysis of gene expression patterns by real time quantitative PCR (RT qPCR). This technique requires well characterized sets of reference genes, which display minimal expression level variations under all analyzed conditions, for data normalization. Sets of suitable reference genes have been described for most widely used model systems including e.g. Arabidopsis thaliana, but not for P. patens. Here, we present a RT qPCR based comparison of transcript levels of 12 selected candidate reference genes in a range of gametophytic P. patens structures at different developmental stages, and in P. patens protonemata treated with hormones or hormone transport inhibitors. Analysis of these RT qPCR data using GeNorm and NormFinder software resulted in the identification of sets of P. patensreference genes suitable for gene expression analysis under all tested conditions, and suggested that the two best reference genes are sufficient for effective data normalization under each of these conditions.

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PLOS ONE: Yield Trends Are Insufficient to Double Global Crop Production by 2050

PLOS ONE: Yield Trends Are Insufficient to Double Global Crop Production by 2050 | plant cell genetics | Scoop.it

Several studies have shown that global crop production needs to double by 2050 to meet the projected demands from rising population, diet shifts, and increasing biofuels consumption. Boosting crop yields to meet these rising demands, rather than clearing more land for agriculture has been highlighted as a preferred solution to meet this goal. However, we first need to understand how crop yields are changing globally, and whether we are on track to double production by 2050. Using ~2.5 million agricultural statistics, collected for ~13,500 political units across the world, we track four key global crops—maize, rice, wheat, and soybean—that currently produce nearly two-thirds of global agricultural calories. We find that yields in these top four crops are increasing at 1.6%, 1.0%, 0.9%, and 1.3% per year, non-compounding rates, respectively, which is less than the 2.4% per year rate required to double global production by 2050. At these rates global production in these crops would increase by ~67%, ~42%, ~38%, and ~55%, respectively, which is far below what is needed to meet projected demands in 2050. We present detailed maps to identify where rates must be increased to boost crop production and meet rising demands.

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News: Concern grows over fire blight treatment options among organic producers after oxytetracyclin antibiotic ban (2013)

News: Concern grows over fire blight treatment options among organic producers after oxytetracyclin antibiotic ban (2013) | plant cell genetics | Scoop.it

In October 2014, organic regulations in the United States are set to change drastically in the fight against fire blight, a contagious disease that affects apple and pear trees. A regulatory ban established by the National Organic Standards Board will take effect against the antibiotic oxytetracycline to treat the potentially devastating disease. Although the government restriction keeps consumer interests in mind, concern is growing among organic producers about alternative treatment options.

 

Jessica Shade, director of science programs at the Organic Center, explained that organic farmers may not yet have the tools or knowledge necessary to drop oxytetracycline. “It’s one of the only things that has really been proven to prevent fire blight. It’s not the only material out there but it’s the one farmers trust the most,” Shade said. “When farmers are handling trees that they’ve invested thousands of dollars in, they really want to have something they know for sure is going to work when the lives of their trees are at stake. That’s why it has been so widely used up until this point.”

 

Concern about the pending ban does not, however, stem solely from the fact that farmers currently prefer the agent. As Shade explained, the problem is that many do not know what to do without it. “One of the researchers who’s working on this project, David Granatstein, did polls throughout Washington State of organic growers and came up with some really frightening numbers that 70-90% of all organic producers might drop out of organic production if there aren’t alternatives available for them,” Shade said. “It’s not worth it for them to gamble their really expensive trees on organic practices that may put the lives of their trees at risk.”


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Nutritional and functional potential of Beta vulgaris cicla and rubra

Nutritional and functional potential of Beta vulgaris cicla and rubra | plant cell genetics | Scoop.it

Swiss chard (Beta vulgaris cicla, BVc) and beetroot (Beta vulgaris rubra, BVr) are vegetables of the Chenopodiaceae family, widely consumed in traditional western cooking. These vegetables represent a highly renewable and cheap source of nutrients. They can be cultivated in soils with scarce organic material and little light and water. BVc and BVr have a long history of use in folk medicine. Modern pharmacology shows that BVc extracts possess antihypertensive and hypoglycaemic activity as well as excellent antioxidant activity. BVc contains apigenin flavonoids, namely vitexin, vitexin-2-O-rhamnoside and vitexin-2-O-xyloside, which show antiproliferative activity on cancer cell lines. BVr contains secondary metabolites, called betalains, which are used as natural dyes in food industry and show anticancer activity. In this light, BVc and BVr can be considered functional foods. Moreover, the promising results of their phytochemicals in health protection suggest the opportunity to take advantage of the large availability of this crop for purification of chemopreventive molecules to be used in functional foods and nutraceutical products.

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Genetic engineering of yellow betalain pigments beyo... [Sci Rep. 2013] - PubMed - NCBI

Genetic engineering of yellow betalain pigments beyo... [Sci Rep. 2013] - PubMed - NCBI | plant cell genetics | Scoop.it

Betalains are one of the major plant pigment groups found in some higher plants and higher fungi. They are not produced naturally in any plant species outside of the order Caryophyllales, nor are they produced by anthocyanin-accumulating Caryophyllales. Here, we attempted to reconstruct the betalain biosynthetic pathway as a self-contained system in an anthocyanin-producing plant species. The combined expressions of a tyrosinase gene from shiitake mushroom and a DOPA 4,5-dioxygenase gene from the four-o'clock plant resulted in successful betalain production in cultured cells of tobacco BY2 and Arabidopsis T87. Transgenic tobacco BY2 cells were bright yellow because of the accumulation of betaxanthins. LC-TOF-MS analyses showed that proline-betaxanthin (Pro-Bx) accumulated as the major betaxanthin in these transgenic BY2 cells. Transgenic Arabidopsis T87 cells also produced betaxanthins, but produced lower levels than transgenic BY2 cells. These results illustrate the success of a novel genetic engineering strategy for betalain biosynthesis.

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The organization of Physcomitrella patens RAD51 genes is unique among eukaryotic organisms

The organization of Physcomitrella patens RAD51 genes is unique among eukaryotic organisms | plant cell genetics | Scoop.it

Genetic recombination pathways and genes are well studied, but relatively little is known in plants, especially in lower plants. To study the recombination apparatus of a lower land plant, a recombination gene well characterized particularly in yeast, mouse, and man, the RAD51 gene, was isolated from the moss Physcomitrella patens and characterized. Two highly homologous RAD51 genes were found to be present. Duplicated RAD51 genes have been found thus far exclusively in eukaryotes with duplicated genomes. Therefore the presence of two highly homologous genes suggests a recent genome duplication event in the ancestry of Physcomitrella. Comparison of the protein sequences to Rad51 proteins from other organisms showed that both RAD51 genes originated within the group of plant Rad51 proteins. However, the two proteins form a separate clade in a phylogenetic tree of plant Rad51 proteins. In contrast to RAD51 genes from other multicellular eukaryotes, the Physcomitrella genes are not interrupted by introns. Because introns are a common feature of Physcomitrella genes, the lack of introns in the RAD51 genes is unusual and may indicate the presence of an unusual recombination apparatus in this organism. The presence of duplicated intronless RAD51 genes is unique among eukaryotes. Studies of further members of this lineage are needed to determine whether this feature may be typical of lower plants.

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Molecular Plant Pathology: Top 10 plant-parasitic nematodes in molecular plant pathology

Molecular Plant Pathology: Top 10 plant-parasitic nematodes in molecular plant pathology | plant cell genetics | Scoop.it

Yay! This OA review joins the list of excellent MPP "Top 10s" including viruses, bacteria and fungi. Let's hear it for the multicellular animal parasites! Can you guess which species is number one? (Hint - it's the one affecting the plant in this photo).

Thanks to the USDA's amazing Scott Bauer for this photo http://www.forestryimages.org/browse/detail.cfm?imgnum=1323037.


Via Mary Williams, Jennifer Mach
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Natural variation and artificial selection in four genes determine grain shape in rice - Lu - 2013 - New Phytologist - Wiley Online Library

Natural variation and artificial selection in four genes determine grain shape in rice - Lu - 2013 - New Phytologist - Wiley Online Library | plant cell genetics | Scoop.it
The size of cultivated rice (Oryza sativa) grains has been altered by both domestication and artificial selection over the course of evolutionary history. Several quantitative trait loci (QTLs) for grain size have been cloned in the past 10 yr. To explore the natural variation in these QTLs, resequencing of grain width and weight 2 (GW2), grain size 5 (GS5) and QTL for seed width 5 (qSW5) and genotyping of grain size 3 (GS3) were performed in the germplasms of 127 varieties of rice (O. sativa) and 10–15 samples of wild rice (Oryza rufipogon).Ten, 10 and 15 haplotypes were observed for GW2, GS5 and qSW5. qSW5 and GS3 had the strongest effects on grain size, which have been widely utilized in rice production, whereas GW2 and GS5 showed more modest effects.GS5 showed small sequence variations in O. sativa germplasm and that of its progenitor O. rufipogon. qSW5 exhibited the highest level of nucleotide diversity. GW2 showed signs of purifying selection. The four grain size genes experienced different selection intensities depending on their genetic effects. In the indica population, linkage disequilibrium (LD) was detected among GS3, qSW5 and GS5.The substantial genetic variation in these four genes provides the flexibility needed to design various rice grain shapes. These findings provide insight into the evolutionary features of grain size genes in rice.
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Plant breeding for nutrition-sensitive agriculture: an appraisal of developments in plant breeding - Christinck & Weltzien (2013) - Food Sec

Plant breeding for nutrition-sensitive agriculture: an appraisal of developments in plant breeding - Christinck & Weltzien (2013) - Food Sec | plant cell genetics | Scoop.it

Plant breeding for nutrition-sensitive agriculture (NSA) has to address the various aspects of food and nutrition security by taking on an integrated approach. In our article, we summarize past and current developments in plant breeding that are relevant to nutrition in this broader context. We outline how plant breeding can contribute to availability of, access to and utilization of food, and give examples of how the concept of NSA is differently addressed in selected plant breeding projects.

 

Effective targeting towards the needs of vulnerable groups seems to be a key success factor. Differences exist with regard to the underlying concept of technology diffusion, the importance given to agrobiodiversity for improving food and nutrition security, and the degree and quality of participation of target groups...

 

Commercial breeding needs to be complemented by other initiatives and institutions that focus particularly on food and nutrition security of vulnerable groups. Any efforts to further harmonize agricultural, nutrition, health, environmental, and educational policies, also with international policy frameworks and obligations, could help to create an enabling policy environment for NSA... 

 

Food fortification in general means enriching basic foods with particular micronutrients, mostly vitamins or minerals, such as iron. However, this requires industrial processing of food and functioning food distribution systems - and presupposes that the target group has access to such food systems. Biofortification could help to overcome this bottleneck, as the food harvested would already contain the critical nutrients, irrespective of further processing and distribution pathways... 

 

In fact, biofortification efforts have been successful in various crops – in the sense that the micronutrient content of some crop varieties has been increased. The most renowned outcome is the successful development of an orange-fleshed sweet potato variety with higher ß-carotene content, which has been introduced to farmers in Mozambique and Uganda, resulting in documented higher levels of Vitamin A intake of children and other vulnerable groups. 

 

Biofortification may sound like a special breeding technology, which, in fact, it is not: basically, it means nothing more than including a nutritional objective into a breeding program. It thus includes the normal steps of a conventional breeding program... 

 

As it does not seem to be realistic to grow one and the same variety of a crop worldwide, the solution is seen in backcrossing the newly bred HarvestPlus varieties with locally adapted or existing commercial varieties in the target regions. HarvestPlus thus relies on the breeding expertise of the CG centers and their partners in the national agriculture research programs (NARS), and allies with NGOs, government programs and the private sector to reach the target population groups... 

 

The most prominent outcome so far is orange-fleshed sweet potato containing higher levels of ß-carotene, compared to the white-fleshed varieties that are commonly grown in many African countries. The orange-fleshed sweet potatoes were introduced in Mozambique and Uganda in 2007... The adoption rate among the farmers targeted by the project was high, with 77% of farmers continuing to grow OFSP in Mozambique and 65 % in Uganda. Children and women of the participating households consumed OFSP, and Vitamin A deficiencies were reduced with higher intake. For example, OFSP accounted for 78% of the Vitamin A intake of children aged below 3 years in participating households in Mozambique, and 53 % in Uganda... 


Via Alexander J. Stein
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Alexander J. Stein's curator insight, August 28, 2013 11:15 PM

"The most renowned outcome is the successful development of an orange-fleshed sweet potato variety with higher ß-carotene content... resulting in documented higher levels of Vitamin A intake of children and other vulnerable groups... compared to the white-fleshed varieties that are commonly grown in many African countries." >> Different colour in crops need not be an unsurmountable problem...

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PNAS: Integration of responses within and across Arabidopsis natural accessions uncovers loci controlling root systems architecture

PNAS: Integration of responses within and across Arabidopsis natural accessions uncovers loci controlling root systems architecture | plant cell genetics | Scoop.it

"Our study also highlights a strategy for intersecting experimentally perturbed phenotypes within a laboratory strain with those observed across a panel of natural variants to uncovergenetic mechanisms underlying plasticity and natural variation for any evolved trait of interest."


Via Mary Williams
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Mary Williams's curator insight, August 27, 2013 10:32 AM

Phenotypic plasticity of an individual recapitulates phenotypic diversity across natural variants - nice study!

Mary Williams's comment, August 27, 2013 12:48 PM
Thanks to Andres Zurita aka Plant Gene Seeker, for pointing out this paper (http://www.scoop.it/t/plant-gene-seeker-pgs)
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Plant biology: Electric defence

The mammalian nervous system can relay electrical signals at speeds approaching 100 metres per second. Plants live at a slower pace. Although they lack a nervous system, some plants, such as the mimosa (Mimosa pudica) and the Venus flytrap (Dionaea muscipula), use electrical signals to trigger rapid leaf movements. Signal propagation in these plants occurs at a rate of 3 centimetres per second — comparable to that observed in the nervous system of mussels. On page 422 of this issue, Mousavi et al.1 address the fascinating yet elusive issue of how plants generate and propagate electrical signals. The authors identify two glutamate-receptor-like proteins as crucial components in the induction of an electrical wave that is initiated by leaf wounding and that spreads to neighbouring organs, prompting them to mount defence responses to a potential herbivore attack.

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Science Special Issue: Smarter Pest Control (2013)

Science Special Issue: Smarter Pest Control (2013) | plant cell genetics | Scoop.it

Science's Special Issue on Smarter Pest Control includes news and reviews on the plant immune system, pesticide's effect on young brains, and preventing suicides by locking up pesticides.

 

The Pesticide Paradox
Martin Enserink et al.

 

Infographic: Pesticide Planet
A global look at the uses, benefits, and drawbacks of pesticides.


A Lethal Dose of RNA
Kai Kupferschmidt
A new generation of genetically modified crops will kill insects by silencing their genes.

 

The War Against Weeds Down Under
Erik Stokstad
For decades, Australia's wheat farmers have had the worst weed problem in the world. Now, nonchemical weapons are helping to turn the tide.

 

Vietnam Turns Back a 'Tsunami of Pesticides'
Dennis Normile

Convincing Vietnamese rice farmers to use less pesticide came down to letting them see the benefits for themselves.

 

In Rural Asia, Locking Up Poisons to Prevent Suicides
Mara Hvistendahl
Pesticide ingestion accounts for one-third of the world's suicides. Can a simple plastic lockbox keep toxic chemicals out of desperate people's hands?

 

Growing Up With Pesticides
Amanda Mascarelli
Long-term studies of the effects of pesticides and other environmental chemicals on the very young brain are coming up with worrisome results.

 

Special Issue Review:

 

Current Challenges and Trends in the Discovery of Agrochemicals
Clemens Lamberth et al.

 

Pivoting the Plant Immune System from Dissection to Deployment
Jeffery L. Dangl et al.

 

Evaluating Pesticide Degradation in the Environment: Blind Spots and Emerging Opportunities
Kathrin Fenner et al.

 

Wildlife Ecotoxicology of Pesticides: Can We Track Effects to the Population Level and Beyond?
Heinz-R. Köhler and Rita Triebskorn

 


Via Kamoun Lab @ TSL
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julien levy's comment, August 18, 2013 1:07 PM
I like the cover! when you know how much of our fresh fruit and vegetables in the US are imported ... and at what cost!
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Control of root system architecture by DEEPER ROOTING 1 increases rice yield under drought conditions

Control of root system architecture by DEEPER ROOTING 1 increases rice yield under drought conditions | plant cell genetics | Scoop.it

The genetic improvement of drought resistance is essential for stable and adequate crop production in drought-prone areas1. Here we demonstrate that alteration of root system architecture improves drought avoidance through the cloning and characterization of DEEPER ROOTING 1 (DRO1), a rice quantitative trait locus controlling root growth angle. DRO1 is negatively regulated by auxin and is involved in cell elongation in the root tip that causes asymmetric root growth and downward bending of the root in response to gravity. Higher expression of DRO1 increases the root growth angle, whereby roots grow in a more downward direction. Introducing DRO1 into a shallow-rooting rice cultivar by backcrossing enabled the resulting line to avoid drought by increasing deep rooting, which maintained high yield performance under drought conditions relative to the recipient cultivar. Our experiments suggest that control of root system architecture will contribute to drought avoidance in crops.

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Visit to vandalized Golden Rice field trial - IRRI (2013)

IRRI and PhilRice officials visit the Golden Rice field site that was vandalized... A crowd of 300 had stormed the Department of Agriculture (DA) Regional Field Unit 5's (RFU5) Bicol Experiment Station, overwhelming the police and guards, and vandalizing the research plots of Golden Rice... 

 

Regional Executive Diretor Bragas said that they were taken by surprise. They had assembled DA officials and staff in the office, waiting for the group to come in and sit down for a peaceful dialogue. Instead, the militants poured into the compound, overwhelmed the police and village security, broke down a section of the fence surrounding the research area, and entered, uprooted, and trampled the crop. 

 

The officials shared that there were farmers in the group, but they just watched and stayed on the sidelines. Local customs and traditions dictate that the destruction of a living field brings bad fortune – Bicolanos refer to it as "Bosung". Those who entered the field to vandalize were mostly young men and some covered their faces. 

 

The local officials and the Institutional Biosafety Committee (IBC) recounted that the rallyists had been assembled in Legazpi City the day before, and brought overnight to Naga City in a convoy of about a dozen jeepneys. In Naga City they had been housed in local hotels. It was reported that the group included foreigners. 


Via Alexander J. Stein
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Alexander J. Stein's curator insight, August 11, 2013 10:57 PM

Interesting to read how little regard the anti-GMO activists apparently had for local customs, traditions and beliefs (which otherwise they probably claim to be dear to their heart), simply overpowering local farmers and stakeholders rather than empowering them. (A jeepney can easily accommodate more than a dozen passengers, i.e. a dozen jeepneys can have bussed in more than half of the "farmers" from Legazpi City who vandalised the field trial.) 

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Reannotation and extended community resources for the genome of the non-seed plant Physcomitrella patens provide insights into the evolution of plant gene structures and ...

Reannotation and extended community resources for the genome of the non-seed plant Physcomitrella patens provide insights into the evolution of plant gene structures and ... | plant cell genetics | Scoop.it
The moss Physcomitrella patens as a model species provides an important reference for early-diverging lineages of plants and the release of the genome in 2008 opened the doors to genome-wide studies.
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Purification and characterization of a betanidin glucosyltransferase from Amaranthus tricolor L catalyzing non-specific biotransformation of flavonoids

Purification and characterization of a betanidin glucosyltransferase from Amaranthus tricolor L catalyzing non-specific biotransformation of flavonoids | plant cell genetics | Scoop.it

Betacyanins are the major pigments present in Amaranthus tricolor, a leafy vegetable consumed globally. The terminal glycosyltaion of the aglycone betanidin is an important step in the biosynthesis of this natural red antioxidant pigment. A betanidin 5-O-glucosyltransferase (BGT) was fully purified to 134 folds (specific activity, 265.2 nkat.mg−1) from the red amaranth by ammonium sulfate precipitation followed by hydrophobic interaction, anion exchange and size exclusion chromatography. Homogeneity of the purified protein was confirmed by 2-dimensional polyacrylamide gel electrophoresis (2D PAGE). The molecular weight of the enzyme determined by liquid chromatography mass spectrometry (LC-MS) was found to be 62.8 kDa. Furthermore, the enzyme glycosylated flavonoids (kaempferol and quercetin) but not anthocyanidins, presence of which is mutually exclusive to betacyanin accumulating plants. The apparent Km (344 ± 2.34 μM) and Vmax (17.24 μM min−1) of the enzyme were determined by LC- MS/MS. Peptide mass fingerprinting of the purified protein showed 38.4% coverage of peptide masses with anthocyanidin 3-O-glucosyltransferase from Zea mays. Study on this purified enzyme, for the first time, revealed its role of glycosylation in biosynthesis of betacyanin in A. tricolor and indicates promiscuous substrate-specificity.

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Studies on Nonenzymatic Oxidation Mechanisms in Neobetanin, Betanin, and Decarboxylated Betanins - Journal of Agricultural and Food Chemistry (ACS Publications)

Studies on Nonenzymatic Oxidation Mechanisms in Neobetanin, Betanin, and Decarboxylated Betanins - Journal of Agricultural and Food Chemistry (ACS Publications) | plant cell genetics | Scoop.it

A comprehensive nonenzymatic oxidation mechanism in betanin plant pigment as well as its derivatives, 2-decarboxybetanin, 17-decarboxybetanin, 2,17-bidecarboxybetanin, and neobetanin, in the presence of ABTS cation radicals was investigated by LC-DAD-ESI-MS/MS. The main compounds formed during the first step of betanin and 2-decarboxybetanin oxidation are 2-decarboxy-2,3-dehydrobetanin and 2-decarboxyneobetanin, respectively. In contrast to betanin, the reaction mechanism for 2-decarboxybetanin includes more oxidation pathways. Parallel transformation of 2-decarboxybetanin quinone methide produces neoderivatives according to an alternative reaction that omits the presumably more stabile intermediate 2-decarboxy-2,3-dehydrobetanin. The main oxidation product after the first reaction step for both 17-decarboxybetanin and 2,17-bidecarboxybetanin is 2,17-decarboxy-2,3-dehydrobetanin. This product is formed through irreversible decarboxylation of the 17-decarboxybetanin quinone methide or by oxidation of 2,17-bidecarboxybetanin. Oxidation of neobetanin results primarily in a formation of 2-decarboxy-2,3-dehydroneobetanin by a decarboxylative transformation of the formed neobetanin quinone methide. The elucidated reaction scheme will be useful in interpretation of redox activities of betalains in biological tissues and food preparations.

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Targeted knockout in Physcomitrella reveals direct actions of phytochrome in the cytoplasm

Targeted knockout in Physcomitrella reveals direct actions of phytochrome in the cytoplasm | plant cell genetics | Scoop.it

The plant photoreceptor phytochrome plays an important role in the nucleus as a regulator of transcription. Numerous studies imply, however, that phytochromes in both higher and lower plants mediate physiological reactions within the cytoplasm. In particular, the tip cells of moss protonemal filaments use phytochrome to sense light direction, requiring a signaling system that transmits the directional information directly to the microfilaments that direct tip growth. In this work we describe four canonical phytochrome genes in the model moss species Physcomitrella patens, each of which was successfully targeted via homologous recombination and the distinct physiological functions of each gene product thereby identified. One homolog in particular mediates positive phototropism, polarotropism, and chloroplast movement in polarized light. This photoreceptor thus interacts with a cytoplasmic signal/response system. This is our first step in elucidating the cytoplasmic signaling function of phytochrome at the molecular level.

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Increase in β-ionone, a carotenoid-derived volatile in zeaxanthin-biofortified sweet-corn - Gallon &al (2013) - Ag Food Chem

Increase in β-ionone, a carotenoid-derived volatile in zeaxanthin-biofortified sweet-corn - Gallon &al (2013) - Ag Food Chem | plant cell genetics | Scoop.it

Carotenoids are responsible for the yellow color of sweet-corn... but are also potentially the source of flavor compounds from the cleavage of carotenoid molecules. The carotenoid-derived volatile, β-ionone was identified in both standard yellow sweet-corn ('Hybrix5') and a zeaxanthin-enhanced experimental variety ('HZ') designed for sufferers of macular degeneration.

 

As β-ionone is highly-perceivable at extremely low concentration by humans, it was important to confirm if alterations in carotenoid profile may also affect flavor volatiles...

 

Delaying harvest of cobs resulted in a significant increase of both carotenoid and β-ionone concentrations, producing a six-fold increase of β-ionone in 'HZ', and a two-fold increase in 'Hybrix5', reaching a maximum of 62 µg/kg FW and 24 µg/kg FW, respectively.


Via Alexander J. Stein
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Alexander J. Stein's curator insight, June 29, 2013 5:44 PM

Interesting that cultivation practices (delayed harvesting) can have such an impact. This means the impact of biofortification may be improved further through more extension work.