A review of Tobacco in Gene Editing
Introduction to the Tobacco Plant
Tobacco entered the European World with the start of the Columbian exchange, and it hasn’t left since. It was given to Columbus, and quickly spread across Europe and Africa as a miracle plant that can cure pain. Tobacco quickly became the primary tool for riches, both in cultivating wealth and in flaunting it. The American South grew it as one of the cash crops to send to the British Empire. Tobacco wasn’t the greatest plant for the soil, however, as it looted the soil of any possible nutrients along with cotton production. To solve this, settlers moved west, turning Native land into their own to grow tobacco. Across time, the tobacco industry soon spread across the Midwest and all throughout the globe. With that, monopolies grew hard. The possibilities for glory and gold quickly consolidated into a few companies, most notably being the British-American Tobacco company, American Tobacco, and many government backed Tobacco plants.
Current State of Tobacco
The world produced 6.09 million tons of Tobacco in 2018, with a total worldwide industry of $923 billion. A few companies in Phillip Morris, the British American Tobacco Company, and CNTC control a large portion of the market. This tobacco is used to get one thing and one thing alone: Nicotine. With the entire plant able to be used, only one compound is extracted and used. We can do so much more.
Possibilities for Gene Editing
Out of all the crops in the world, tobacco has a strong case for one of the best plants for gene editing. With 4.2 million hectares of land specifically used to cultivate tobacco, the impact that a better plant could have can change a substantial portion of the globe. The plant itself can produce much more than nicotine, as it is full of alkaloids and beneficial compounds. With a shift in focus from nicotine to other compounds, tobacco can be used in medical and transportation settings among others. Tobacco can finally shift from an evil to a possible boon to humanity.
Tobacco can also produce cotinine and anatabine in addition to nicotine, amongst other compounds. Cotinine has the potential to fight against diseases such as Alzheimer’s, PTSD, Depression, and other mental debilitations, while anatabine has anti-inflammatory properties. Nicotine itself is only shown to be mildly addictive in animal studies, and can possibly benefit in some cases. That said, addiction is a real thing. Even ‘mildly’ addictive drugs can still lead to paths of ruin for the users, which is why the utmost caution must be used to handle tobacco with people. With a changed tobacco, a more specific plant can be created to target one specific organic compound, instead of only focusing on nicotine while completely ignoring the rest.
A factory is simply an organization that produces a creating product, and a biofactory is similar. A biofactory produces products, but those products are all organic compounds, and the biofactory itself is something organic as opposed to a combination of people and plastic. Nonfood crops are usually the best to test cutting edge technology on as opposed to food crops because any ill effects an initial test could have will not come out of mass consumption. Through New Plant Breeding Techniques, fragments of DNA can enter the tobacco plant to turn it into a biofactory.
Methods of DNA editing:
- Agroinfiltration: A temporary expression of genes into a plant to produce the desired protein following the input of certain nucleic acids (transient expression).
- Synthetic Biology: The plant is created in a lab to develop certain traits and produce the desired protein.
- Chassis Improvement: Simplifying the genome to specifically produce a few desired proteins and nothing else, therefore not wasting energy.
- Gene Circuits: Synthesis of DNA segments that control each other’s levels to enable controllable outputs of proteins.
- Genome Editing: Either replacing or inserting gene to produce a certain protein
- Intragenesis: The transfer of a DNA segment between organisms
- Hairy root cultures: The gram negative (very, very small) soil bacteria Rhizobium rhizogenes infects tobacco to produce hairy root cultures for organic compound production. The hairy root cultures are both easily identifiable and grow quickly, meaning that change is visible.
One of the things we can produce from tobacco is the fat itself. The tobacco seed lipid content is around 36–41% of it’s dry weight, meaning that it’s a fairly fatty seed. There are two main genes that influence this: The TT8 gene, and the NtAn1 gene. The TT8 gene negatively influences lipid production, while the NtAn1 influences it positively. If both can be altered, with the TT8 gene removed and the NtAn1 gene boosted, lipid weight content can improve by as much as 15%. This tobacco can be turned into oil through a press, which can then react with alcohol to produce a biodiesel. This biodiesel has the same function as a diesel, meaning that it can possibly fuel methods of transportation.
One of the primary ingredients in antimalarial drugs is artemisinic acid. In the olden days, it was derived from the Chinese Wormwood plant. Production is localized to tropical East Asian areas, and completely dependent on the crop, of which there isn’t enough. High costs are rampant in both the natural and chemical synthesis of it. Tobacco can help with that. Tobacco can be infiltrated through one of the methods of DNA editing, and is able to produce artemisinic acid with the transient expression of the CYP71AV1 gene. Along with yeast and other methods, the cost of this potential life saving drug can go down by 30–50%.
Nicotine has the potential to do some good. It is similar to caffeine in that focus and creativity can increase. The main problem itself is the way it is consumed. Cigarettes themselves burn tar that harm the lungs, and e-cigs have burning plastic that produce formaldehyde. That isn’t the issue to solve today, but we can alter nicotine production in either way. The NtERF189 and NtERF199 genes regulate nicotine production, and with either the elimination or overexpression of those genes nicotine production can be altered. A less addictive cigarette can be made with low nicotine tobacco, which can turn smokers into non-smokers.
The need for caution
The utmost caution must be taken to make sure that these plants do not harm the soil. The plant itself changes much more than intended in any gene editing experiment, and we must make sure that the plants are safe in the environment we are in. Security and safety must be the primary focus. If anything else is, then the plant is ruined, the environment is ruined, and any chance of testing it again is ruined.
Conclusion and the Future of Tobacco
The potential for tobacco is endless, especially with comparing the baseline. The current state of tobacco can be improved, and gene editing seems to be the way to do it. Tobacco can be turned from a cash crop that harms people through addiction to a plant that can provide anti-malarial drugs and possibly even fuel. Big change to the industry is possible, and is happening right now in labs across the world.
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