Gene

Cell biology

Algorithm

Functional genomics

Composite number

Biology

Materials science

Gene delivery

RNA silencing

Biochemistry

Small interfering RNA

Computer science

Transfection

Carbon fibers

Gene silencing

Computational biology

Nicotiana benthamiana

Genetics

Nanotechnology

RNA-induced silencing complex

Genome

RNA interference

Effector

Genomics

Small RNA

Trans-acting siRNA

PLANT PHYSIOLOGY

The initiation of RNA interference (RNAi) by topically applied small interfering RNA has potential applications for plant functional genomics, crop improvement and crop protection, but the primary obstacle for the development of this technology is the efficient delivery of RNAi effectors into the cell. The plant cell wall is a particularly challenging barrier for the delivery of macromolecules because many of the transfection agents that are commonly used with animal cells produce nanocomplexes that are significantly larger than the size exclusion limit of the cell wall. Here, we illustrate the use of a class of very small nanoparticles, called carbon dots, for delivering small interfering RNA into the model plants Nicotiana benthamiana and tomato (Solanum lycopersicum). Low-pressure spray application of these formulations with a spreading surfactant resulted in strong silencing of GFP transgenes in both species. The delivery efficacy of carbon dot formulations was also demonstrated by the silencing of endogenous genes that encode two subunits of magnesium chelatase, an enzyme necessary for chlorophyll synthesis. The strong visible phenotypes observed with the carbon dot-facilitated delivery were validated by measuring significant reductions in the target gene transcript and/or protein levels. Methods for the delivery of RNAi effectors into plants, such as the carbon dot formulations described here, could become valuable tools for gene silencing in plants with practical applications in plant functional genomics and agriculture.

Carbon Dots for Efficient Small Interfering RNA Delivery and Gene Silencing in Plants