Emulsifier And Dispersant, Biodegradable Compound Emulsifier,Chemical Compound Emulsifier Henan chinamian foods CO.LTD , https://www.ooossooo.com
New cloning technology will significantly shorten the time to study plant genes
A piece of plant or animal DNA may contain hundreds or thousands of genes. Each gene encodes a different protein. Each protein has important significance for the survival or growth of the organism. For researchers, how to separate individual genes and study the function of each gene is a real challenge? A difficult process that often requires the entire lab to spend years trying and failing. A collaborative research team at Stanford University and Britain's John Innes Centre is now inventing a new technology that can significantly simplify the process. New technology allows researchers to identify specific genes in months rather than all year. In six months, the researchers completed work that would have taken several years to complete and identified an interesting gene. They are convinced that the extension of this technology to other species will help accelerate the pace of research by researchers. This new technique, called transcription-based cloning, was published on PNAS (Proceedings of the National Academy of Sciences) on March 30, 2004. The biggest advantage of this new technology is its application to large and complex genomes like plants. Sharon R. Long, one of the authors of the article, is an expert in bacterial and plant molecular biology and is the chair of the School of Humanities and Sciences at Stanford University. She and her colleagues used the new cloning technology to isolate and identify a Medicago truncatula (or Barrel medic) is a very important gene in the process of nitrogen fixation, verrucosa is a member of the legume family, and alfalfa and peas are close relatives. The DNA of cricket contains thousands of genes. Finding the function of each gene by traditional methods will be an extremely time consuming task. Traditional plant genomics methods use artificial mutagenesis and then look for mutant genes. For example, a large number of seeds are treated with radiation at random, these seeds are cultured in the laboratory, mutants with altered phenotypes are selected, the DNA of the mutants is studied until the mutant gene is found, and the function is further studied. If researchers want to find genes related to the growth of roots, they must first find the mutants with defective roots and perform incomparable large-scale DNA analysis until they find the mutant gene that causes the defect. All organisms are inseparable from the nitrogen source. Only by the action of nitrogen-fixing bacteria can the nitrogen in the air be converted into a nitrogen source that can be used by the organism. Most legumes allow Azotobacter to invade the roots to form root nodules and establish a mutually beneficial symbiotic relationship with Azotobacter, thereby obtaining a sufficient nitrogen source. This is also the reason why farmers plant earthworms as fertilizer in the fields during fallow. The purpose of the researchers is to find genes that allow specific plants to associate with Azotobacter. It may take 3 to 5 years for such studies to be performed in the cockroaches using traditional methods, partly because this process requires cross-fertilization of two generations of plants. In order to shorten the process, the researchers reasoned by reverse thinking: Under normal circumstances, the synthesis of proteins is guided by genes, information is transferred from DNA to RNA through transcription, RNA carries genetic information into the cytoplasm and used as a template Synthetic protein. The erroneous information transfer of the mutated gene results in nonsense RNA and is rapidly degraded, and the amount of this RNA in the mutant cell will be very low. But in turn whether this situation is true? That is, if a very low level of an RNA from a mutant can be represented by a defect gene? If so, researchers can look for RNA with reduced expression, identify its sequence and then locate this gene. How legumes interact with nitrogen-fixing bacteria is still a mystery. In some unknown role, the root cell can recognize the signal of Azotobacter within a few minutes. The intracellular calcium ion concentration increases rapidly and then slowly decreases, forming a calcium ion peak almost every minute. This repeats for several hours. In order to better study this phenomenon, the researchers found that a mutant could produce calcium peaks but could not form a symbiotic relationship with Azotobacter and compared wild-type ticks with mutants. Using gene chip technology, the researchers examined RNA levels in 10,000 genes in two phenotypic plants. The researchers found that the DMI3 gene has a very low level of RNA in the mutants. The DMI3 gene expresses proteins and regulates calcium in normal cells. The response of the tobacco plant protein is similar. This result convinced researchers that the DMI3 gene is involved in the calcium stress response of plants. Last month, a Dutch and French research team also published similar results in Science. They used almost 4 years to complete the identification of DMI3. This study took only six months. This study, while deeply studying the process of nitrogen fixation, points out a quick and effective method for identifying important plant genes for cloning and can be applied to various plants.