As a recovering introvert, I’ve been wanting to present some tips and tricks to our NCBiotech Jobs Network audience, with the hope that my networking suggestions would help them as they network to a new job in 2013.
Here is the post I wrote for our Staff Blog (with editing help from my colleague Jim Shamp) along with my slides.
In December I had the chance to present at RTP180: Philanthropy. I figured that if the North Carolina Biotechnology Center gives money to support scientific research, that made us philanthropists. So I jumped at the chance to talk about our work to a new audience.
See my post for our Staff Blog and scroll to the bottom to see a video link to the event.
And check out the awesome Storify by my colleague Robin Deacle.
A recent study shows that some farmers in the European Union (EU) would grow genetically modified (GM) crops if they were permitted to by the EU. Currently, the EU allows GM crops to be imported, but Bt maize (insect resistant corn) and Amflora potato (a starch potato grown for industrial use, rather than for food) are the only GM crops approved for cultivation in EU member states.
Over 600 farmers in six European countries were asked their opinions about growing two important GM crops: herbicide tolerant (HT) maize and HT oil seed rape (OSR). They were surveyed on how issues such as economic impact, environmental and technical concerns, peer or social pressure, and crop yield would affect their decisions whether to grow these crops.
Half of the farmers surveyed in the OSR-growing countries of Czech Republic, Germany, and UK were enthusiastic about growing GM HT crops.
In the maize cultivation regions of Spain, France, and Hungary, one third of the farmers surveyed were likely to adopt GM HT maize. One third were not willing to adopt the new technology, and one third were undecided.
Farmers’ opinions were primarily based on economic factors. Greater income from higher crop yields and lower weed control costs were the most important positive influences. Increased seed cost, and difficulty in marketing grain from GM crops were the biggest negative influences. Interestingly, social and peer pressures had the least influence on farmers’ willingness to adopt GM technology.
Areal FJ, Riesgo L, & Rodríguez-Cerezo E (2011). Attitudes of European farmers towards GM crop adoption. Plant biotechnology journal, 9 (9), 945-57 PMID: 21923717
Wheat is an important staple food, but the gluten in wheat can cause illness or allergy in some people. Gluten is a term used to describe two families of proteins: glutenins and gliadins. People with Celiac Disease (CD) have painful digestive symptoms when they eat gluten. The symptoms are caused by the gliadin, not the glutenin, in wheat flour. Wheat is also a common cause of food allergies. One allergy in particular, Wheat-Dependent Exercise Induced Anaphylaxis (WDEIA) occurs when sensitive individuals ingest gluten, then engage in intense physical exercise. Like CD sufferers, people with WDEIA are reacting to gliadin, not glutenin. In fact, people with WDEIA react to a subset of gliadin proteins called omega-5 gliadins. In an effort to create a wheat flour that WDEIA-sensitive individuals can eat without risk, USDA researchers Susan Altenbach and Paul Allen used genetic engineering to reduce only the omega-5 gliadin proteins in wheat.
Altenbach and Allen attempted to reduce the omega-5 gliadin proteins in wheat grain, those that cause the WDEIA allergy, using a technique called RNAi*. The genetically engineered (GE) wheat grain from plants generated by this technique had reduced omega-5 gliadin protein, as predicted, apparently without affecting other gliadin proteins in the grain. Although not yet tested, the hope is that WDEIA susceptible individuals will be able to eat products made from this wheat without risk of allergic reaction.
As described in a previous post, RNAi was used by other researchers (see Gil-Humanes, et al., 2010) to reduce gliadin proteins in wheat. The GE wheat generated by Gil-Humanes and colleagues has reduced amounts of all gliadins, not just the omega-5 subset that causes WDEIA symptoms. Will flour made from reduced-gliadin GE wheat alleviate symptoms in people who have either CD or WDEIA? By extension, will flour made from GE wheat which is lower only in the omega-5 gliadins reduce WDEIA but not CD? Future research will answer these questions.
*RNA interference (RNAi) is a technique for preventing a gene from making protein. For more information, see this explanation on MedicineNet.
Altenbach, S., & Allen, P. (2011). Transformation of the US bread wheat ‘Butte 86’ and silencing of omega-5 gliadin genes GM Crops, 2 (1), 66-73 DOI: 10.4161/gmcr.2.1.15884
Gil-Humanes, J., Pistón, F., Tollefsen, S., Sollid, L.M., Barro, F. (2010). Effective shutdown in the expression of celiac disease-related wheat gliadin T-cell epitopes by RNA interference. PNAS 107, 17023 – 17028. DOI: 10.1073/pnas.1007773107
When we speak about genetically modified organisms (GMOs), we often think first about herbicide tolerant (Round-Up Ready) or insect resistant (BollGard) crops. But plants can be genetically engineered perform functions other than insect resistance and herbicide tolerance. My first post described one example: using plant genetic engineering to improve the quality of life for celiac disease patients. Bioremediation, the use of GMOs to reduce chemical contaminants in the environment, is another application of genetic engineering.
Bioremediation is the process of using live organisms to degrade toxic compounds. Phytoremediation is bioremediation using plants as the live organisms. In 2010 a research group at Nankai University published the results of their studies on phytoremediation of the herbicide, atrazine.
Atrazine is one of the most widely used herbicides in crops. Limiting weeds in the field reduces competition for water and nutrients. In corn production, for example, weed control using atrazine can lead to yield increases of 1–6%. However, atrazine is a relatively stable compound, degraded slowly in soil by microbes. It may be carcinogenic and has been associated with birth defects and endocrine disruptions. Atrazine accumulation in the soil might damage crops that are planted after atrazine treatment of fields. For these reasons, it is important to have a method to degrade atrazine in soil. One approach to increasing degradation of atrazine and other pesticides is phytoremediation.
Among the soil microbes that naturally degrade atrazine are Pseudomonas and Arthrobacter. These bacteria contain the atrazine chlorohydrolase gene (atzA), that converts atrazine to the non-toxic hydroxyatrazine. The Nankai University researchers genetically engineered (GE) plants to add the atzA gene. They tested the resulting
GE plants for their ability to degrade atrazine in soil.
Non-GE plants grew as well as GE plants if the plants were grown in soil without atrazine. But in soil containing atrazine, non-GE plants were shorter and weighed less than plants genetically engineered to contain the atzA gene. Since atrazine acts by destroying chlorophyll in the leaves, the GE plants were tested for changes in chlorophyll content. When GE and non-GE plants were grown in soil containing atrazine, the chlorophyll in non-GE leaves decreased. The chlorophyll level of GE plants remained unchanged, indicating protection of the chlorophyll and therefore the plant by the introduced gene.
But will the GE plants remediate contaminated cropland? That is, can they remove atrazine from the soil, reducing damage to successive crops and reducing potential effects on human health? It’s still unclear how these plants will perform in the field. However, after growing GE plants in soil containing atrazine for 90 days, no atrazine remained in the soil. While preliminary, these data suggest that GE plants can be used for phytoremediation of an important herbicide in soil.
H Wang, X Chen, X Xing, X Hao, and D Chen. 2010. Transgenic tobacco plants expressing atzA exhibit resistance and strong ability to degrade atrazine. Plant Cell Reports 29: 1391 – 1399. DOI: 10.1007/s00299-010-0924-7
Genetic engineering of plants can reduce the need for chemical insecticides. This, in turn, can improve food safety, and reduce energy inputs and cost. In recent posts I described genetically engineering plants to produce their own pesticides, specifically TMOF and chitinase. I also discussed the effects that the pesticides created by those plants had on insect larvae. Savvy readers would have noticed that the effects on insects have been promising, but not stellar. It’s hard to get very enthusiastic about delayed weight gain as a measure of success!
That’s the reason the Rao research group at Università di Napoli took their project one step further and combined two biopesticides into a single plant. In a paper published in the 2010 Insect Biochemistry and Molecular Biology journal, these researchers tested the combination of plant-made TMOF and plant-made chitinase against larvae of the tobacco budworm.
Classical methods were used to breed genetically engineered (GE) plants producing TMOF with GE plants producing chitinase. The hybrid offspring produced both pesticidal proteins. Tobacco budworm (Heliothis virescens) larvae were fed leaves from the hybrid plants, or from GE plants producing either TMOF or chitinase, or from non-GE plants. The insects that were fed leaves from the TMOF-producing plants or the chitinase-producing plants developed more slowly than those fed with leaves from non-GE plants. But insects that were fed leaves from the dual-biopesticide plants developed even more slowly than the insects fed with leaves from plants producing either TMOF or chitinase alone. Most important for crop protection, approximately 75% of larvae fed on hybrid plants died. This suggests that GE plants producing both TMOF and chitinase protect themselves better against damage from insect larvae than plants producing only one of the proteins.
L Fiandra, I Terracciano, P Fanti, A Garonna, L Ferracane, V Fogliano, M Casartelli, B Giordana, R Rao and F Pennacchio. 2010. A viral chitinase enhances oral activity of TMOF. Insect Biochemistry and Molecular Biology 40: 533 – 540. DOI:10.1016/j.ibmb.2010.05.001