The Ri (root-inducing) plasmid of Agrobacterium rhizogenes carries agropine genes. When A. rhizogenes infects a plant, a portion of the Ri plasmid DNA enters the host plant cell and causes the production of hairy roots at the site of action. A foreign gene could be inserted into modified Ri plasmid and the recombinant DNA (plasmid) could be introduced into plants in much the same way as with the Ti plasmid of A. tumefaciens. The recombinant Ri plasmid would induce the production of hairy roots after the infection of the host plant. Scientists are now trying to use these hairy roots as potential drug factories. In a new study, scientists have successfully maintained a transgenic hairy root culture alive for 4-and-a-half years, and they hope that this could be a great source of continuous drug production. Read the full story here.
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Scientists have created genetically modified mouse which manifests remarkable physical behaviour. It can run 6 kms at a speed of of 20 metres per minute for five hours, eats 60% more than normal mouse, does not put on weight, enjoys an active sex life to an old age, and lives longer. The mouse produces very little lactic acid, which causes muscle cramps, a feature associated with endurance athletes. All in all a very strong mouse. The phosphonenolpyruvate carboxykinase (PEPCK-C) is an enzyme of gluconeogenesis pathway. The formation of glucose from nonhexose precursors is gluconeogenesis. The enzyme PEPCK-C catalyzes the conversion of oxaloacetate to phosphoenolpyruvate using GTP as the phosphate donor. The transgenic mice carrying the gene for PEPCK-C, under the control of skeletal actin gene promoter, were created. The transformed mice showed a highly increased production of this enzyme. This led to the enhancement of physical and behavioral characters of the mice. Professor Hanson, who led the team of researchers responsible for the creation of the “mighty mouse”, said, “They are metabolically similar to Lance Armstrong biking up the Pyrenees. They utilise mainly fatty acids for energy and produce very little lactic acid. They are not eating or drinking and yet they can run for four or five hours. They are 10 times more active than ordinary mice in their home cage. They also live longer – up to three years of age – and are reproductively active for almost three years. In short, they are remarkable animals.”On the possibilities of trying the same in humans he said, “We humans have exactly the same gene. But this is not something that you’d do to a human. It’s completely wrong. We do not think that this mouse model is an appropriate model for human gene therapy. It is currently not possible to introduce genes into the skeletal muscles of humans and it would not be ethical to even try.” Read the full story here.
via: The Independent
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This post is about two recent developments in the field of biotechnology and environmental science.
1) Agrobacterium-mediated transformation is the method of choice for inserting foreign genes into the plant genome. Through this method one gene could be introduced at a time in a single experiment. However, to introduce two foreign genes, one needs to develop two separate plant lines each carrying one gene. The plants of the two lines are then cross bred to get both the genes in one plant. The process is quite laborious and takes a lot of time to complete. Besides, integration of the foreign gene into the plant genome can disrupt any native gene; or the foreign gene may get silenced and not expressed. To overcome these problems a team of scientists from the University of Chicago, the University of North Carolina and Chromatin, Inc., has developed a new method for constructing artificial plant mini-chromosomes. These are the rings of plant DNA that can be used to carry multiple genes in plant cells in one go. The work has been published in the October 19, 2007, issue of PLoS-Genetics. The team has developed maize mini-chromosomes (MMCs) that “…can introduce an entire “cassette” of novel genes into a plant in a way that is structurally stable and functional.” These mini-chromosomes could be suitably used as vectors for the transfer of two or more than two genes simultaneously, and would thereby save the time and effort required for lengthy and laborious hybridization experiments needed to transfer two genes in a plant genome. This would also cut down expenses involved in such experiments. The MMCs created also have maize centromere sequences in them. These sequences help them maintain independently of the maize genome and newly introduced genes remain separate from the genome. This also helps their efficient transfer to the next generation in the Mendelian fashion. Thus these MMCs behave much like ordinary chromosomes.
You can read the full story here.
2) The second story deals with the use of algae as biofuel. Several companies are already working on the use of algae as biofuels. But LiveFuels Alliance, funded by LiveFuels Inc based in Menlo Park, CA, is trying to tap the oil producing potential of algae and hopes to replace gallons of fossil fuels with algae-based biocrude by 2010. Algae synthesize oil naturally. The raw algae is processed to “…make biocrude, the renewable equivalent of petroleum, and refined to make gasoline, diesel, jet fuel, and chemical feedstocks for plastics and drugs.” To quote from the story, “Theoretically, algae can yield between 1,000 to 20,000 gallons of oil per acre, depending on the specific strain.” What is important is that LiveFuels Alliance is a national initiative led by Sandia National Laboratories, a U.S. Department of Energy National Laboratory, and in the next 3 years it would sponsor several labs and hundreds of scientists, which makes it the largest endeavor focused on commercial biofuel production from algae. Read the whole story here. via: Inhabitat
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