I'm sick, I don't need injections, I don't need to take medicine, just eat a few fruits. Even eating carrots can make people immune and prevent diarrhea. This is the future life that scientists design for people. With their unremitting efforts, this scene is getting closer and closer to mankind. In the National Plant Genetics Research Center (Fang Rongxiang Laboratory) of the Institute of Microbiology, Chinese Academy of Sciences, a variety of light incubators are filled with carrots, tobacco, and other plants that have just undergone "genetic surgery." Researchers are busy with the transfer of the rotavirus antigen protein gene and viral E. coli antigen proteins into carrots. The project began to receive support from the National 863 Program in 2003. Fang Rongxiang, the project leader and an academician of the Chinese Academy of Sciences, said that although the specific time is difficult to determine, from the current study, the use of carrots for oral vaccine production is just around the corner. At that time, taking medicine may be a delicious treat for the patient. The idea of ​​a research and development of a vaccine for vegetable transformation has been confirmed in 1990. That year, for the first time, two foreign scientists published a method for the production of vaccines using plants in the form of patents. They converted the surface antigen of Streptococcus mutans in transgenic tobacco. After animal experiments proved that this antigen can induce mice to produce specific antibodies. In the past decade, there have been many reports on the use of plants to produce oral vaccines. Although most immunization experiments are still in animal experiments, up to now, there have been at least five kinds of oral vaccines for plants that have entered clinical trials. The first edible plant vaccine for clinical trials was genetically modified potatoes resistant to bacterial diarrhea. This landmark research proves that consumption of transgenic plants can effectively stimulate human immune response. However, this landmark study did not address infantile severe diarrhea. Rotavirus is the main cause of severe diarrhea in infants and young children, but there is still no effective and safe vaccine. For safety reasons, animal-derived rotavirus vaccines or reconstituted vaccines for animal viruses and human viruses have been tested internationally, but have been discontinued due to intussusception in infants and young children. Therefore, the idea of ​​using genetically modified carrots to produce rotavirus antigens and making humans immune through oral genetically modified carrots was supported by the National 863 Program. Under the leadership of Academician Fang Rongxiang, the laboratory is focusing on the use of carrots as a bioreactor to produce oral medicine. The key technology of the vaccine. The predecessor of the National Plant Genetics Research Center (Fang Rongxiang Laboratory) of the Institute of Microbiology, Chinese Academy of Sciences is the Key Laboratory of Biotechnology of the Chinese Academy of Sciences. As early as the end of the 1980s, the coat protein gene of tobacco mosaic virus and cucumber mosaic virus was successfully established. Into tobacco, transgenic tobacco resistant to two viruses was obtained. At the same time, a group of talents who have mastered the techniques of plant molecular biology have been cultivated, and they have been at the forefront in the research of transgenic plants. Why Carrot Researchers chose plants as carriers because plants have many inherent advantages over animals and microbes. Academician Fang Rongxiang said that some vaccines can be effective for life, and some vaccines (such as cholera and tetanus) need regular intake. If the latter vaccine is used as a carrier, it will be more convenient to eat it directly, and it can also avoid cross infection caused by incomplete disinfection of the syringe. This oral vaccine takes full advantage of the plant's edible nature and its low-cost nature, and is currently the main product that uses plants as bioreactors. In addition, plants can be grown on farmland in large areas with low production costs. Many can be eaten raw. Plants do not become the host of human or animal pathogens, and they are easy to store and transport. At present, the plant carriers used in the plant reactors to express medical proteins are mainly concentrated in a few plants such as tobacco, potatoes, and tomatoes. “However, the cost of isolating and purifying the target protein from tobacco is higher, and the loss of target protein activity when the potatoes are cooked will be about 50%. Raw food-based transgenic plants can avoid these shortcomings, and they can be omitted by injection and refrigeration. And utensils." That's why they chose carrots as carriers. "Compared with tomatoes and lettuce, carrots are more easily transported, store-resistant, yield-rich, nutrient-rich, and can be grown anywhere in the world. They can be eaten raw and processed into drinks," Academician Fang Rongxiang said. Gene Drugs Growing in the Land So, how can plants that can be eaten as medicines be produced? Similar to the production process of various genetically modified foods, researchers first need to transfer the genes of a particular protein into common plants, multiply and screen them for several generations, and finally obtain a homozygous plant line that stably expresses a specific protein. The validity of the antigenic protein in the transgenic plant and the detection of the biosafety are then examined. At this time, these new members of the plant family can walk from the laboratory to the field and reproduce on a large scale. We specifically look at the process of producing genetically modified carrots that can prevent diarrhea. First, the rotavirus gene is extracted, the gene for the virus surface protein is cloned into a plant expression vector, the vector is transferred into Agrobacterium, and the vector containing the viral protein gene is transferred to the plant cell and integrated into the plant genome by Agrobacterium. In this, the transgenic plant cells can be regenerated to produce a complete plant. Then zoom in on this detail. After the carrot seeds are sterilized and planted in the medium, it will sprout like a bean sprout. The cotyledons (beans) and roots must be cut off, and then the hypocotyls (bean sprout roots) are cut into small pieces. These small pieces are soaked in Agrobacterium broth carrying the vector containing the viral protein gene and Agrobacterium will be adsorbed on the lower embryos. At the cut-out of the shaft, the vector containing the viral protein gene is transferred into the plant cells. After cultivation, a plurality of single plant seedlings are grown at the cut-out, and after they are rooted in the culture medium, they are moved to a pot. Each of these regenerated seedlings carries an imported foreign gene and expresses the corresponding foreign protein. Next, a molecular level test is performed. The identified plants containing the rotavirus antigen gene were grown, grown, and seeded and planted for the next generation. The genetically modified carrot that grows out must first undergo animal experiments. After success, it is necessary to do toxicological experiments to ensure that there are no poisons to humans, the environment and other animals. These procedures are completed before they can enter clinical trials and eventually go to market. "We have now obtained three kinds of transgenic carrots that have the rotavirus protein gene, each of which has yielded dozens of seeds. Now in winter, we have planted part of it into the greenhouse." Chen Xiaoying, an associate researcher at the laboratory, told reporters. “There is still a lot of work to be done. It needs to be completed step by step.†Therefore, if you want to eat this carrot, you have to wait patiently for some time. At present, the world’s major developed countries and some developing countries have formulated their own laws and regulations governing GMOs and are responsible for assessing their safety. China is no exception. "As a result, the products that are finally available will be strictly controlled in terms of security," said Chen Xiaoying. First, genetically modified carrots are absolutely safe for the user. In the final product, no selection markers will be included, and the target genes transferred are all state-approved commercialized exogenous genes. Second, carrots will be cultivated in a greenhouse that is completely isolated from the outside world. It will not cause adverse gene drift to other species, nor will it cause pollution to surrounding farmland and the environment. Moreover, before the launch of genetically modified carrots, GM carrots will also undergo four stages of the listing of genetically modified foods: the pilot phase, the environmental release phase, the production trial phase, and the production certification application phase. At the time of listing, these special carrots will “wear†a uniform genetically modified logo and attach a detailed food instruction to the consumer.