Shrink the giant: scale down the citrus tree to a model system to investigate the RNA interference efficiency

ABSTRACT

Virus-induced silencing gene technology has been increasingly used; however, a controversy exists among researchers about whether using the sense or antisense orientation of the gene target is more efficient. Herein, instead of using the entire citrus tree, a reduced system consisting of a single leaf, 5 cm of the stem and a few roots was established to fairly compare between the sense or antisense orientation of phytoene desaturase gene (pds) in the Citrus tristeza virus vector, for improved RNAi efficiency. Although the virus titers were similar in the two cases, the gene expression of pds was significantly lower when using the antisense orientation than using the sense orientation. I hypothesize that the extra effect from use of antisense orientation is due to the role of subgenomic RNA as a supplemental source for complementary sequences, thus resulting in more RNAi.

KEYWORDS:

• RNAi
• virus-induced gene silencing
• Citrus tristeza virus
• phytoene desaturase

Acknowledgments

The author acknowledges our CREC colleagues for their helpful discussions. I thank Shelley E. Jones for the technical assistance and Lorraine Jones and Floyd Butz for maintaining the trees in greenhouses. This project is funded by the grant no. 201500955-04 from SCRI-NIFA, USDA.

Additional information

Funding

This work was supported by the National Institute of Food and Agriculture [201500955-04];