Plant gene editing through de novo induction of meristems

In vitro cell culture is a bottleneck in the production of transgenic and genome-edited plants: in only a few species it is possible to develop new, modified plants from cell cultures. Furthermore, It is a lengthy process in which new and unintended mutations can occur. This study here describes a new method that can be used as an alternative method to the work in tissue and cell cultures. The new method is intended to generate genome-edited plants faster.
Plants contain special areas in their shoot and roots, so-called meristems, where the cells divide and lead to the growth and development of the entire plant. The scientists have introduced certain genes that regulate the development of these “division zones” into seedlings of tobacco plants via Agrobacterium tumefaciens transformation. As a result, new seedlings were formed on the seedlings, which carried a genetic modification in their genome.
This system was then expanded in a way that the DNA encoding the gene scissors CRISPR/Cas were also inserted into tobacco seedlings together with a specific guide RNA (gRNA). CRISPR/Cas knocked out two genes that are important for the formation of carotenoids (i.e. plant pigments). This enabled the identification of genome-edited seedlings by their white color, because of the lack of the green dye chlorophyll. Some seedlings even developed flowers and seeds that made it possible to pass on the genetically modified changes to the next generation. This process has been used successfully in tobacco, potatoes, tomatoes and grapes.