Human gene increases potato and rice output
Upcycling plastic into synthetic vanilla We live in a world filled with plastic. Unfortunately a large portion of the plastic that affords us daily convenienc- es and life-saving devices ends up in landfills and oceans across the world. In order to combat the growing environ- mental problem of global plastic waste, scientists have begun to pursue alterna- tive methods for recycling plastics. Most of the current methods degrade plastic and use the resulting base molecules to create more plastic materials.
Global population growth and reduced crop yield, due largely to increasing heat and drought, are putting a strain on the food supply throughout the world. For decades, scientists have been working to boost crop production but such processes are usually complicated, and often result only in small changes. In a recent study, scientists made a breakthrough that allows plants to yield more crops and withstand drought stress. A central concept in biology is that DNA is transcribed into RNA which is then translated into protein. Although gene expression is primarily controlled during the transcription of DNA to RNA, scientists discov- ered that it can also be regulated at the RNA level. Chemical markers placed onto RNA modulate which proteins are made and how many. The human FTO protein is the first known protein that erases these chemical marks on RNA. In humans and other animals, FTO is known to affect cell growth. Plants do not express an equivalent to human FTO. Inserting the gene that encodes FTO in both rice and potato plants increased their yield by 50 percent in field tests. The plants grew significantly larger, produced longer root systems, and were better able to withstand stress from drought. Scientists think that FTO controls a process known as m6A modifica- tion which places the chemical markers on RNA. FTO removes m6A marks from RNA to tone down some of the signals that tell plants to slow down and reduce growth. Without the signals telling the plants to slow their growth, the plants have a surge in crop yields. Although this process involves inserting a human gene into plants, scientists are working to discover how to get the same effect using the plant’s existing genome. REFERENCE: Yu Q. et al. RNA demethylation increases the yield and biomass of rice and potato plants in field trials, Nature Biotechnology (2021) DOI: 10.1038/s41587-021- 00982-9.
Scientists discovered a way to reap more value from the plastic recycling process by turning post-consumer plastic into synthetic vanilla flavoring. They used genetically engineered E. coli bacteria to convert terephthalic acid (a molecule derived from a type of plastic called PET) into the high value compound vanillin, which is the prima- ry component of extracted vanilla beans that is responsible for the characteristic vanilla smell and taste. Terephthalic acid and vanillin molecules look structurally similar. The genetically modified E. coli make a few changes to the number of hydrogen and oxygen atoms bonded to the terephthalic acid’s carbon ring, the circular structure in the center of the molecule. These chemical adjustments create vanillin. Further testing is needed to confirm the vanillin produced in this way is suitable for making fragrances and flavorings. The entire process also has to be successfully scaled to produce liters of vanillin. If that hurdle can be overcome, we’ll have a more environmentally friendly process to create this high-demand product.
REFERENCE: Sadler J. et al. Microbial synthesis of vanillin from waste poly(ethylene terephthalate), Green Chemistry (2021) 23(13): 4623-4904. DOI: 10.1039/d1gc00931a.
More details can be found in the Shareable Science blogpost: Upcycling plastic bottles into vanilla flavoring.
whitefly
are so successful at feasting on plants because their genome contains a plant gene that protects the insects from phenolic glycosides, toxins that many plants produce to defend themselves against such pests. This is the first known example of natural gene transfer from a plant to an insect. Scientists think that a virus possibly shuttled genetic material from the plant into the whitefly genome. After the scientists discovered the gene and confirmed it came from plants, they decided to see if inactivating it removed the whitefly's protective edge. The team engineered tomato plants to produce a double-stranded RNA molecule capable of shutting down expression of the gene. Nearly all of the whiteflies that fed on these tomato plants died. With this discovery, scientists can develop crops that are resistant to the whiteflies but that will not cause new harm to other species. REFERENCE: Xia J. et al. Whitefly hijacks a plant detoxification gene that neutral- izes plant toxins, Cell (2021) 184:1693-1705. DOI: 10.1016/j.cell.2021.02.014.
Insect incorporates plant gene to avoid plant defenses
During their 400 million year evolution with their insect foes, plants developed specialized defenses to protect themselves. Whiteflies, a close relative to aphids, are among the most de- structive plant pests, circumventing the defenses of hundreds of types of plants. They drink sap from the plants and excrete a sticky, sweet substance called honeydew that serves as a breeding ground for mold. Whiteflies are also carriers for more than 100 pathogenic plant viruses. Scientists set out to determine how whiteflies manage to evade the defenses of so many plants. They discovered that whiteflies
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