• Production of BT Corn• Martirez, Rjay Mikko • Aspe, Myrina Liahona P. • Baluyot, Kymreigne Fressie C. • What is a BT Corn? • Bt corn is a type of transgenic crop because it contains a gene that has been artificially inserted into it instead from the process of pollination. • Type of genetically modified organism ( GMO ) – . A GMO is a plant or animal that has been genetically modified through the addition of a small amount of genetic material from other organisms through molecular techniques. • What is ‘ BT ‘? • Bacillus Thuringiensis • It produces a toxin specific to certain insects (e.g. moths, beetles, blackflies or mosquitoes). • It is a naturally-occurring soilborne bacterium that is found worldwide. A unique feature of this bacterium is its production of crystal-like proteins that selectively kill specific groups of insects. These crystal proteins (Cry proteins) are insect stomach poisons that must be eaten to kill the insect. Once eaten, an insect's own digestive enzymes activate the toxic form of the protein. • HOW IS IT MADE? • Plant geneticists create Bt corn by inserting selected exotic DNA into the corn plant's own DNA. Seed companies select elite hybrids for the Bt transformation in order to retain important agronomic qualities for yield, harvestability and disease resistance. Three primary components of the genetic package inserted into corn include: • Protein gene. Bt genes, modified for improved expression in corn, produce Cry proteins. Initial Bt hybrids in the United States and Canada include one of three Cry proteins, Cry1Ab, Cry1Ac or Cry9C. Future hybrids may produce other Cry proteins, or proteins from other sources. • Promoter. A promoter controls where and how much of the Cry protein a plant produces. Some promoters limit protein production to specific parts of • Genetic marker. The special gene of interest that was inserted into it is called a transgene.A. • . – This step is the most limiting step in transgenic process because there is only limited information known about specific genes required to enhance the characteristics of plants.N. • HOW IS IT MADE? – Step1: Extracting the desired gene from other organism. The presence of a genetic marker allows seed companies to identify successful transformations.N. – Step 2: Cloning the desired gene of interest – Step 3: Designing the gene – Step 4: Transformation process – Step 5: Plant breeding. • There are primarily 5 steps in creating transgenic crops like Bt Corn: – Step1: Extracting the desired gene from other organism. fragments together.A. that was obtained because a significant amount is needed to be inserted into the desired organism.N. green tissue and pollen) whereas others produce protein throughout the plant.N. ligase. leaves. – First of all the main tools that are involved in this process are restriction enzyme and D.A. The restriction enzymes are like scissors and then D. ligase is the glue that sticks back the ends of the nucleotide sequences.A. Therefore it is used after the restriction enzyme to attach the parts of the D. The next step is to amplify the amount of D. Current examples of markers include genes for herbicide resistance or antibiotic resistance. The gene from Bacillus thuringiensis that produces the crystal toxin protein has been insterted into the DNA of the corn and therefore making it poisonous to insects. the plant (for example. • HOW IS IT MADE? – Step 2: Cloning the desired gene of interest . • HOW IS IT MADE? • Bt corn is a type of transgenic crop because it contains a gene that has been artificially into it instead from the process of pollination. The termination sequence tells the cellular machinery when the end of the gene sequence has been reached.A. to a workable amount. − The promoter sequence must be added for the gene to be correctly placed into the D.N. Now the D.A. The marker genes functions are to aid in identification of plants cells that have the specific integration of the transgene. This process is necessary because only a small percentage of targeted tissue will have the transgene.A.A. is placed into the plasmid of the bacteria and is replicated to produce more of the D. in it and therefore only that specific kind can grow. ensuring that all of the carrier bacteria will have the desired trait. − HOW IS IT MADE? • Step 4: Transformation process . The bacteria that are antibiotic resistant carries the desired D. • HOW IS IT MADE? • Step 3: Designing the gene − This process is necessary because the gene has to undergo several modifications for it to be effectively inserted into a plant.N.N. − The other two parts that are added onto the gene is the termination sequence and a marker gene. The promoter works as an on/off switch that controls when and where in the plan the gene will be expressed. one that has a specific antibiotic mean the other has no antibiotic.A.• The desired gene that was extracted is now subject to a process called polymerase chain reaction(PCR).N. The process of transformation involves the carrier cells to be placed into two medium. a method that is used to amplify the amount D.N. The marker gene usually consists of a protein that encodes for resistance against herbicides or specific antibiotics. of the plant. • At this point an antibiotic resistant gene is also inserted into the plasmid which allows the carrier cell to be amplified successfully through the process of transformation. The bacteria is then subject to the first medium whereby it is growth is significant and then subjected to the other medium whereby only the bacteria that has the antibiotic resistant gene can grow. This process is also known as the micro-projectile bombardment method. Transformation in this process means the change that will be brought upon a cell through introduction of a new D.N.A. When it is activated it enters the plant through the wound and unfortunately this is not known how the D.N.A can be transferred effectively. • • HOW IS IT MADE? Step 5: Plant Breeding • After all of the following process has occurred successfully a process known as tissue culture is used to obtain the whole plant. • How is it made? Advantages of bt corn • Better For The Environment Since GMOs require much less chemicals to thrive. the impact on the environment is lessened. There are two methods how this could be achieved: – This first method is the gene gun method where a gun is used to insert the D.A. from moves to the cytoplasm to the nucleus of the plant. This bacteria is able to infect plant cells with a piece of its D. Also tests are carried out to ensure that the plants have the desired gene and to see the activity and inheritance of the gene. which cause tumors.A. This gun made up of a 6” x 7” x 10” stainless steel chamber that is connected to a 2HP vacuum pump. Scientist have genetically engineered this bacteria so that the gene responsible for tumor is no longer present and is replaced by the gene that is to be inserted into a plant. In this process the plant tissues are grown under controlled environment in a series of medium that contain specific nutrients and hormones. – The other method is with the Agrobacterium bacteria also known as Agrobacterium tumefaciens.N. This process is beneficial because a large fragment of D.A.N. • Resistance To Disease .N. This improves how long they last and stay fresh during transportation and storage. This could develop “superweeds” that have the same resistance properties as the crops. When this pollen is around other plants. • Allergies On The Rise Ever since the introduction of GMO foods. • Keeps It Affordable / Cost Efficiency One of the biggest effects that the use of GMOs has had on our every day life is the prices of produce and other foods. • Less Effective Antibiotics The crops that have been genetically modified have antibiotic properties put into them in order to make them immune to certain diseases. . This keeps the yields high and the prices for the consumers low. the genes of the crops can also be altered to have a better flavor and increased nutritional value • Longer Shelf Life Genetically modified foods have a longer shelf life. • Sustainability GMOs provide a stable and efficient way to sustain enough crops to feed the ever growing population of people in the world. • Increased Flavor and Nutrition Along with resistances to insects and disease. the prices can be much lower • Disadvantages of bt corn • Cross Contamination The pollen from the genetically modified plants is also contaminated. even things like grass or weeds. When you eat these foods these properties are left in your body and can make many antibiotics less effective. but many believe this is due to insufficient research in the area. they cross pollinate. One of the modifications made to the crops is an added resistance to disease that would normally kill off the crops. the amount of childhood food allergies has risen significantly. Since more crops can be yielded. The exact link to GMO has not yet been found. • Not Enough Testing There has been very little testing and research done on genetically modified foods and the long term effects have not been discovered yet. . This makes many people feel uneasy at the high use of these foods.