A new approach for pollen transformation via functionalized silica nanoparticles
Research project 17
Project researchers: Dr. Guy Mechrez and Dr. Ziv Spiegelman

Here we present a new plant transformation technology, which will be applied to pollen grains and avoid plant tissue culture transformation.

Since 1985 Pollen has been an attractive alternative for successful genetic transformation for all species (1). However, transformation to pollen is quite challenging (2). Therefore, enormous research activity is currently focused on this topic. A recently published paper showed a DNA delivery technique called magnetofection to pollen grains via magnetic beads incorporated with DNA in cotton plants (3). This proposed research aims to synthesize magnetic nanoparticles and Janus particles to introduce DNA, RNA, and Cas9 protein to pollen cells. CRISPR/Cas9 system (4) will make the transformation / mutagenesis process more efficient and accurate.

Our plant model in this work is the cucumber. This plant has been chosen due to the following reasons; characterized by separate male and female flowers (Monoecious), easy to grow, short life cycle (getting fruit after one and a half months) and containing plenty of seeds (approximately 200 per fruit).

Figure 1. Confocal images of fluorescent labelled silica nanoparticles inside the N.benthamiana plant leaves. a-c) 24 hours after the infiltration, d-f) 9 days after the infiltration.
Figure 2. Agarose gel electrophoresis of different quantities of plasmid DNA bound to the silica nanoparticles.
Figure 3. Imaging of two differently modified functional Janus particles by Stochastic Optical Reconstruction Microscopy (STORM).


  1. Ohta Y. High-efficiency genetic transformation of maize by a mixture of pollen and exogenous DNA. Proc Natl Acad Sci U S A. 1986 Feb;83(3):715–9.
  2. Touraev A, Stöger E, Voronin V, Heberle‐Bors E. Plant male germ line transformation. Plant J. 12(4):949–56.
  3. Zhao X, Meng Z, Wang Y, Chen W, Sun C, Cui B, et al. Pollen magnetofection for genetic modification with magnetic nanoparticles as gene carriers. Nat Plants. 2017 Dec;3(12):956–64.
  4. Puchta H. Applying CRISPR/Cas for genome engineering in plants: the best is yet to come. Curr Opin Plant Biol. 2017;36:1–8.

Dr. Guy Mechrez
Project researcher

Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem.

Email: guyme@agri.gov.il

Phone: +972-3-9683990

Website: Dr. Guy Mechrez

Research areas:

  • Janus and amphiphilic particles.
  • Advanced Pickering emulsions.
  • Chemical sensors for food safety and quality.
  • Superhydrophobic and anti-fog coatings and surfaces.
  • Individual cell encapsulation.
  • Formulations for bio-pesticides.
  • Smart/active food packing systems.
Dr. Ziv Spiegelman

Dr. Ziv Spiegelman
Project researcher

Plant Protection, Department of Plant Pathology and Weed Research, Agricultural Research Organization, Volcani Institute.

Email: ziv.spi@volcani.agri.gov.il

Phone: +972-3-9683534

Laboratory website

Research areas:

  • Developing novel approaches for viral resistance in vegetable crops.
  • Long-distance and cell-to-cell movement of plant viruses.
  • Interaction of plant viruses with the root system.
  • Viral silencing suppression and its effect on plant development.

Research partners:

Avital Ben-Haim
PhD student

Agricultural Research Organization, Volcani Institute.

Reut Amar Feldbaum
Lab manager at Guy Mechrez lab

Agricultural Research Organization, Volcani Institute.