SEFV

The agronomic application of nanotechnology in
plants (phytonanotechnology) has the potential to
alter conventional plant production systems, allowing
f or the controlled release of agrochemicals (e.g.,
f ertilizers, pesticides, and herbicides) and targetspecif
ic deliv ery of biomolecules (e.g., nucleotides,
proteins, and activators). An improved understanding
of the interactions between nanoparticles (NPs) and
plant responses, including their uptake, localization,
and activ ity, could revolutionize crop production
through increased disease resistance, nutrient
utilization, and crop yield. Herewith, we rev iew
potential applications of phytonanotechnology and
the key processes inv olved in the deliv ery of NPs to
plants. To ensure both the safe use and social
acceptance of phytonanotechnology, the adv erse
effects, including the risks associated with the
transf er of NPs through the f ood chain, are
discussed.
The f ield of nanotechnology has great potential
within plant sciences and plant production systems.
The agronomic application of nanotechnology has
thus f ar received comparativ ely little interest relativ e
to the application within human systems.
We rev iew the potential applications and future
opportunities of nanotechnology in plant sciences,
thereby assisting in bridging the div ide between
human and agricultural nanotechnology.
The application of nanotechnology in plant sciences
will benef it from the development of improv ed
analytical techniques that enable the in situ analysis
of NPs in planta with a low detection limit and high
lateral resolution.
Regardless of the benef its of nanotechnology f or
plant sciences, the principle of ‘saf ety -by-design’
must be heeded to address community concerns
about the potential adv erse effects of nov el
engineered nanoparticles (ENPs) on ecological
sy stems.
Damage-signalling protein shows parallels
between plant, human immune systems
Fuente; www.sciencedaily.com 24 /03/2016
Nov el plant protein signals tissue damage and
makes plants more resistant to certain infections
A protein that signals tissue damage to the human
immune system has a counterpart that plays a
similar role in plants, report researchers at the Boyce
Thompson Institute (BTI).
Prof essor Daniel Klessig and colleagues hav e
identif ied a new damage-associated molecular
pattern molecule or "DAMP" in plants. DAMP
molecules released by injured cells trigger an
immune response in plants and animals. The
researchers describe this protein, called HMGB3, in
a new paper in PLOS Pathogens. Knowledge of
HMGB3, and its human equiv alent, HMGB1,
enhances our understanding of how humans and
plants fight off infections.
Plants and animal tissues use DAMPs to detect
when they are wounded, so that they can promote
healing and to f end off inf ection. DAMPs are alway s
present inside cells, but are released into the
surrounding space in response to tissue damage,
where they activate inf lammatory and immune
responses.
The researchers discov ered the actions of HMGB3
through their investigations of plant and animal
proteins that interact with salicy lic acid, a plant
immune regulator and the main breakdown product
of aspirin. A prev ious study by Klessig's lab f ound
that salicy lic acid blocks HMGB1, a DAMP in
humans that is associated with multiple
inf lammation-related diseases. When they searched
the genome of the model plant Arabidopsis f or genes
coding f or similar proteins, they f ound HMGB3.
They compared the actions of HMGB3 in
Arabidopsis plants to other known plant DAMPs, and
measured the protein's ability to help plants f ight off
gray mold inf ection.
"We injected the protein into the extracellular space
of the plant and then examined different layers of
immune activ ity," said lead author Hyong Woo Choi,
a senior research associate at BTI. The protein
triggered a signaling cascade involv ed in the plant
immune response, activated the expression of genes
inv olved in def ense, started callose deposition -- a
protective thickening of the cell walls -- and made the
plants more resistant to gray mold inf ection.
They found that, like human HMGB1, HMGB3 also
interacts with salicy lic acid, which inhibits its
activ ities. The immune-boosting effects of HMGB3 in
gray mold-infected plants were erased when the
researchers added salicylic acid.
"The identif ication of salicylic acid's shared targets
and mechanisms of action in plants and animals
enable us to translate what has been learned in one
sy stem to the other, said Klessig. "For example,
glyceraldehy de 3-phosphate dehy drogenase is
another shared target. It is involv ed in the replication
of several plant and animal v iruses, including
hepatitis A, B and C v iruses in humans and tomato
bushy stunt virus in plants. Notably, salicy lic acid
binding to this target suppresses replication of the
plant v irus."
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