With a new approach to green genetic engineering, researchers have succeeded in making rice and potato plants not only more tolerant of drought, but also increasing their yield by 50 percent. To do this, the researchers introduced a human gene into the plants that encodes a protein called FTO. This changes certain modifications on the RNA of the plants and thus promotes their growth. The researchers hope to achieve the same effect in the future without alien genes.
So that the DNA of living beings can be read, the blueprints encoded in it are first translated into so-called messenger RNA (mRNA). This in turn serves as a guide for the production of proteins. This process is regulated on many levels. Modifications to the DNA ensure, for example, that certain genes are read more frequently, less often or not at all. Similar modifications can also be found on the RNA. Chemical groups are attached to components of the RNA that influence how which proteins are produced.
Modification for more yield
A team led by Qiong Yu from Beijing University in China has now made use of this mechanism. They focused on so-called N6-methyladenosine modifications (m6A) in plants. In this modification, methyl groups are attached to the RNA at certain points. “Previous results have indicated that m6A influences the growth and physiology of plants,” the researchers explain. “That is why we speculated that manipulating the m6A level could be a new way of influencing plant growth.”
Humans and animals, but not plants, have a gene that encodes a protein called FTO. This is able to remove methyl groups from the RNA, so to speak, to reverse m6A modifications. Yu and her colleagues introduced this gene into rice plants. The result: “The expression of FTO promotes root growth, the formation of root buds, photosynthetic efficiency and drought tolerance,” the researchers report. They also found that the rice plants produced up to three times more yield under laboratory conditions. In the field, the yield increased by 50 percent. The height of the plants did not change.
Transferable to different types of plants
The researchers also achieved similar results with representatives of a completely different family of plants: potatoes. Here, too, the outdoor yield increased by around 50 percent. “That suggests an exciting level of universality,” says co-author Chuan He of the University of Chicago. “The change is really dramatic and it works with almost every type of plant that we have tried so far with.” Compared to other genetic engineering methods, the modification is very easy to carry out.
In view of climate change in particular, the researchers see great potential in their discovery: The study shows that the m6A modification of RNA is crucial for controlling plant growth. Their modulation could therefore offer a new, promising approach to significantly increasing plant production, the team said. “The new technology offers the possibility of modifying plants so that they are adapted to ongoing global warming,” says He. “We depend on plants for many things – everything from wood, food and medicine to flowers and oil – and now we may have found a way to increase the feedstock we can get from most plants.”
Is it also possible without foreign DNA?
The researchers now want to take a closer look at the underlying mechanisms so that they may be able to achieve the same effect in the future without introducing foreign genes into the plant. “It seems plants already have that level of regulation, and all we’ve done is tap into it,” says He. “So the next step would be to figure out how to do it with the existing genetics of the plant.”
From He’s point of view, RNA modification opens up numerous areas of application: “There are other consequences of climate change beyond nutrition,” he says. “Perhaps we could grow grasses in threatened areas that can withstand drought. Perhaps we could train a tree in the Midwest to have longer roots so it is less likely to tip over in strong storms. There are so many possible uses. “
Source: Qiong Yu (Beijing University, China) et al., Nature Biotechnology, doi: 10.1038 / s41587-021-00982-9