Biomedical Engineering Reference
In-Depth Information
a conjugation-like process. A set of virulence gene complex present in
the bacterium along with the Ti plasmid accomplish the transformation
process. Initially, two virulence proteins, VirA and VirG help activate the
T-DNA transfer in
A. tumefaciens
and this step is mediated by the phenolic
compound, acetosyringone. Subsequently, other
vir
genes VirC, VirD and
VirE2 facilitate the T-DNA transfer and integration into host cells (Fig 3).
Additional
vir
genes, VirF, VirH and VirE3 that complete the virulence
gene complex may be not necessary for the fungal transformation
(Michielse et al. 2004) as demonstrated in
A. awamori
. Knight et al. (2010)
demonstrated that
A. tumefaciens
and
V. albo-atrum
co-cultivated on the
plant wound site facilitated interactions between them to generate
V.
albo-atrum
transformants naturally without the exogenous addition of
acetosyringone. These results confi rmed that the plant tissue alone was
able to activate the
vir
gene complex to allow the transformation of
V.
albo-atrum
in-planta
.
Figure 3.
A simplifi ed overview of the
A. tumefaciens
T-DNA transfer system in fungi.
(Color image of this fi gure appears in the color plate section at the end of the topic.)
The development of ATMT protocols varies among different fungi,
including
M. oryzae
and
V. dahliae
. Several parameters, such as fungal
starting material,
Agrobacterium
strain, acetosyringone concentration
and co-cultivation conditions (time and temperature) etc. influence
