Researchers from the universities of Tokyo, Tohoku and Tamagawa obtained the first predictable high yield from four new varieties of rice and three varieties of rapeseed. All of them are mutants obtained by a method of DNA editing in the mitochondria of the parent plant that was not available until recently. It is fundamentally different from the manipulation of the basic DNA genome and holds great promise in agriculture.
Mitochondria are figuratively called the "powerhouses" of the cell, as they are responsible for generating energy. And they have their own isolated DNA, which in animals is small and insignificant in comparison with the basic DNA in the cell nucleus. In plants, everything is different, their mitochondrial DNA is huge, very confused, many of the mechanisms of gene expression are still not understood by scientists, and some mitochondria do not have their own DNA at all. It is not surprising that the study of this area was not previously conducted due to the mass of difficulties.
However, scientists are not satisfied with the situation when most of the plant genome remains inaccessible for editing - this sharply limits the genetic diversity of plants, inhibits the development of useful varieties. Therefore, despite all the complexity, the work is already underway and the first successes were achieved by specialists from Japan. They have reworked the animal genome editing mechanism into a technology called mitoTALENs, which works like a scissor to cut individual genes from DNA.
Scientists have discovered a gene responsible for the factor "cytoplasmic male sterility", leading to infertility in male plants. After the removal of this gene, several new varieties were created in which the factor of infertility was minimized. The new varieties have produced excellent yields, but more importantly, the first step in editing mitochondrial DNA opens up a vast field of activity for geneticists and breeders. This process will not be fast at all, on the contrary, but it has already started and it inspires hope.