New technologies and strategies for grapevine breeding through genetic transformation

GABRIELA NATALIA CAMPOS; CONSTANZA SOLEDAD CHIALVA; MIRAS SILVANA LORENA; DIEGO LIJAVETZKY

Frontiers in Plant Science

Frontiers Media

Año: 2021

1664-462X

Grapevine, as other woody perennials, has been considered a recalcitrant crop to produce transgenic plants. Since the productionof transgenic and/or edited plants requires the ability to regenerate plants from transformed tissues, this step is often thebiggest bottleneck in the process. The objective of this work is to review the state-of-the-art technologies and strategies toimprove grapevine transformation and regeneration, focused on three aspects: (i) problems associated to grapevinetransformation; (ii) genes that promote grapevine regeneration; and (iii) vehicles for gene delivery. Concerning the first aspect, itis well documented that one of the main factors explaining the low success rate in obtaining transgenic plants is the regenerationprocess. After transgenic integration into receptor cells, tissue culture is required to regenerate transgenic seedlings fromtransformed cells. This process is time consuming and often requires the addition of environmentally damaging reagents(antibiotics and herbicides) to the culture medium to select transgenic plants. On the other hand, the expression of the so-calledDevelopmental Regulators (DR) genes, which induce specific development programs, can be used to avoid traditional tissue culturemethods. The ectopic expression of specific combinations of DR in somatic cells has the potential to induce de novo meristems indiverse crops, including grapevine. Successful genome editing by de novo reprogramming of plant meristems in somatic tissues hasbeen reported. Moreover, it has been shown that the expression of certain transcription factors can increase the regenerationefficiency in wheat, citrus, and rice. Finally, recent reports showed the use of nanoparticles, such as carbon dots (CDs) asattractive alternative to Agrobacterium- and biolistic-mediated plant genetic transformation. In this way, the use of antibiotics inculture media is avoided, overcoming the loss of viability of plant tissues and accelerating the regeneration processes. It has beenshown that CDs can act as a vehicle to transport plasmids to plant cells in transient transformation in several crops withoutnegative impacts on photosynthesis or growth. Based on these advances, it is possible to combine these new available strategiesand technologies to overcome the regeneration problems of species such as grapevine and other crops considered as recalcitrant.