Agriculture Reference
In-Depth Information
modification of nanoparticles to improve efficacy, stability, and accuracy making it
less time-consuming.
Keywords Bioconjugation • Biotransformation • Nanoparticles • Transgenic
vehicle
10.1
Introduction
Genetic engineering is a powerful technique to create genetic modifications for the
selected trait(s) and to allow transfer and integration of a gene of interest into the
genome of host. DNA delivery is the most important aspect of gene transfer in
plants to develop the transgenics. There are several methods used for gene transfer,
but all of them have some or the other limitations. Small size of the nanoparticles
(1 nm
10
9
m) allows them to bypass the cell barriers like cell wall and plasma
membrane and deliver genes into the cell of living systems, and they can also be
used as a transgenic vehicle for nucleic acid (Rai et al.
2012
).
Nanoparticles-mediated gene transfer methods are new and have the potential to
directly transfer DNA into the cells, achieving stable integration and rapid expres-
sion of the transgene. Nanoparticles are the particles at atomic or molecular level
with dimension in nanoscale (Ball
2002
; Roco
2003
). The nanoparticles behave
differently and exhibit different physiochemical properties as compared to their
bulk counterpart (Nel et al.
2006
). Nanoparticles are formed from a variety of
materials, and their action depends upon their chemical composition, size, and
shape (Brunner et al.
2006
). On the basis of their origin, Roberto and Ruffini
(
2009
) classified nanoparticles into three major types as: (1) natural nanoparticles;
(2) incidental nanoparticles, also called as waste or anthropogenic particles, which
are mainly formed due to the man-made activities; and (3) engineered nanoparticles
or nanomaterials. The engineered nanomaterials can be classified into four types,
viz., carbon based, metal based, dendrimers, and composite nanoparticles. Nowack
and Bucheli (
2007
) have highlighted the role of modified nanomaterials for improv-
ing many sectors of the economy, such as consumer products, pharmaceutical
materials, cosmetic products, transportation, energy, and agriculture.
The nanoparticles, which can be used as a vector for gene transfer, include
calcium phosphate, carbon based, silica, gold, magnetite, strontium phosphate,
magnesium phosphate, and manganese phosphate (Potrykus
1991
). The nanoparti-
cle-mediated gene transfer mechanism is reported as follows: initially,
nanoparticles recognize and get adsorbed on the cell membrane, and later these
nanoparticles are internalized by endocytosis. During this process, if DNA escapes
out, before the fusion of endosome with lysosome, this escaped DNA successfully
enters into the cell cytoplasm, where its degradation by nucleases can occur.
However, for an efficient transfer, it must be protected from nucleases and enter
into the nucleus. Generally, the DNA enters into the nucleus with the help of
nuclear pore complexes (NPCs) which are large number of proteins, forming a
¼
