Rational Design Principles for the Transport and Subcellular Distribution of Nanomaterials into Plant Protoplasts

Abstract

The ability to control the subcellular localization of nanoparticles within living plants offers unique advantages for targeted biomolecule delivery and enables important applications in plant bioengineering. However, the mechanism of nanoparticle transport past plant biological membranes is poorly understood. Here, a mechanistic study of nanoparticle cellular uptake into plant protoplasts is presented. An experimentally validated mathematical model of lipid exchange envelope penetration mechanism for protoplasts, which predicts that the subcellular distribution of nanoparticles in plant cells is dictated by the particle size and the magnitude of the zeta potential, is advanced. The mechanism is completely generic, describing nanoparticles ranging from quantum dots, gold and silica nanoparticles, nanoceria, and single-walled carbon nanotubes (SWNTs). In addition, the use of imaging flow cytometry to investigate the influence of protoplasts' morphological characteristics on nanoparticle uptake efficiency is demonstrated. Using DNA-wrapped SWNTs as model nanoparticles, it is found that glycerolipids, the predominant lipids in chloroplast membranes, exhibit stronger lipid-nanoparticle interaction than phospholipids, the major constituent in protoplast membrane. This work can guide the rational design of nanoparticles for targeted delivery into specific compartments within plant cells without the use of chemical or mechanical aid, potentially enabling various plant engineering applications.

Targeted delivery of nanomaterials with chemical cargoes in plants enabled by a biorecognition motif

“…QD with β-cyclodextrin molecular baskets conjugated with targeting peptides (Chl-QD) allow the targeted delivery of biochemical cargoes into chloroplasts. The β-CD molecular basket composed of seven cyclic oligosaccharides enables "hostguest" formation with ascorbic acid or methyl viologen 36,37 and can form inclusion complexes with a broad range of biomolecules 12,17,38,39 . Furthermore, QD have a high and stable fluorescence enabling in vivo tracking within plant tissues and cellular compartments 40 .…”

“…Interestingly, the zeta potential of Chl-QD is significantly lower than MPA-QD (P < 0.001) ( Fig. 2c) indicating that models based on increased nanoparticle charge for promoting chloroplast delivery 12,38,39 are not sufficient to predict plant organelle localization of nanomaterials guided by biomolecule recognition motifs in plants in vivo.…”

“…Tuning hydrophobicity of the peptide recognition motif is also likely to affect the nanoparticle translocation in plant cells as it was shown by previous studies coating nanoparticles with amphiphilic polymers 29 . Models of plant cell and chloroplast uptake based on nanoparticle size and charge alone using polymeric ligands 38,39 do not explain why Chl-QD coated with biorecognition motifs with lower zeta potential magnitude than MPA-QD exhibit higher colocalization rates with chloroplasts. This indicates that nanoparticle-plant interaction models should incorporate engineered biomolecule coatings and acquired coronas for making accurate predictions of the distribution of nanoparticles in plants.…”

Plant Nanobionic Sensors for Arsenic Detection

“…[32,33] In addition, their surface properties can be engineered to target different plant organs or subcellular organelles. [34][35][36] Arsenite is chosen as the target analyte because it is the predominant form of arsenic in anaerobic paddy soils which can be taken up efficiently by crops through silicon transporters in the roots. [12,37,38] Previous studies have shown that guanine (G) and thymine (T) nucleotides can form strong hydrogen bonds with the hydroxy (OH) groups of arsenite.…”

Species-independent analytical tools for next-generation agriculture

“…Nanoparticles with dimensions below the size exclusion limit of the cell wall (~20-50 nm) have the ability to access the plant cell interior 111 . It has been shown that the zeta potential and size of nanoparticles govern their subcellular localization within plant cells, enabling the specific targeting of various compartments such as the chloroplasts and the cytosol 75,112,113 . Furthermore, targeting moieties can be grafted onto the surface of nanostructures to direct their localization to the nucleus, mitochondria or other organelles within a plant cell 114,115 .…”