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bioRxiv · 10.1101/2023.12.12.571232

Advancing Virus-Induced Gene Silencing in Sunflower: key factors of VIGS spreading and a novel simple protocol

Mardini, M.·Kazancev, M.·Ivoilova, E.·Utkina, V.·Vlasova, A.·Demurin, Y.·Soloviev, A.·Kirov, I.
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Abstract

Virus-Induced Gene Silencing (VIGS) is a versatile tool in plant science, yet its application to non-model species like sunflower demands extensive optimization due to transformation challenges. In this study, we aimed to elucidate the factors that significantly affect the efficiency of Agrobacterium-VIGS in sunflowers. After reaffirming a number of approaches, we concluded that the seed vacuum technique followed by 6 h of co-cultivation produced the most efficient VIGS results. Genotype-dependency analysis revealed varying infection percentages (62-91%) and silencing symptom spreading in different sunflower genotypes. Additionally, we explored the mobility of tobacco rattle virus (TRV) and phenotypic silencing manifestation (photo-bleaching) across different tissues and regions of VIGS-infected sunflower plants. We showed the presence of TRV is not necessarily limited to tissues with observable silencing events. Finally, time-lapse observation demonstrated a more active spreading of the photo-bleached spots in young tissues compared to mature ones. This study not only offers a robust VIGS protocol for sunflowers but also provides valuable insights into genotype-dependent responses and the dynamic nature of silencing events, shedding light on TRV mobility across different plant tissues.

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Mardini, M., Kazancev, M., Ivoilova, E., Utkina, V., Vlasova, A., Demurin, Y., Soloviev, A., Kirov, I.. 2023-12-13. Advancing Virus-Induced Gene Silencing in Sunflower: key factors of VIGS spreading and a novel simple protocol. https://doi.org/10.1101/2023.12.12.571232

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