Grapevine fanleaf degeneration disease is of viral origin and appears on the list of the most pathogenic vine diseases. As part of a Franco-Hispano-Belgian consortium led by CNRS and INRA, Christophe Ritzenthaler and his collaborators have succeeded in producing plants that are totally immune to grapevine fanleaf degeneration disease. For this, they used very small antibodies, also called nanobodies, isolated from camels. Both in laboratory plants and in rootstocks of grapevines grown in vitro, these very small antibodies have demonstrated their unique ability to completely and swiftly neutralize the virus following its inoculation.
This work is published in Plant Biotechnology Journal.
More : Nanobodies are small peptides derived from single-chain antibodies found in camelids (camel, llama, alpaca etc). Discovered in the 1990s, nanobodies are the smallest antibody type molecules and are of great interest in biomedical biotechnology. However, their potential in agrobiotechnology is still largely underestimated. Scientists have isolated nanobodies directed against Grapevine fanleaf virus (GFLV), the principal agent of grapevine fanleaf degeneration disease. Remarkably, these antibodies possess antiviral activity against GFLV when they are produced directly by plants. This antiviral activity is broad spectrum, because it is effective against many distinct strains of GFLV. It is also functional during the transmission of the virus by its nematode vector. Although the mechanism responsible for virus neutralization in the plant remains unknown and the social acceptability of this technology remains to be demonstrated, this proof of concept study reveals that it is possible to effectively combat grapevine fanleaf degeneration disease. When shall we expect to encounter nanobodies in our vineyards?
Typical symptoms of Grapevine fanleaf degeneration disease in the Cramant vineyard in the heart of the Côte des Blancs in Champagne. © Christophe Ritzenthaler
The prevalence and severity of Grapevine fanleaf degeneration disease pose a serious threat to the viability of vineyards around the world, particularly on the most valuable plots of land, which have been cultivated for centuries. In France alone, it is estimated that 60% of cultivated areas are affected by this disease, causing considerable economic losses.