Genome sequencing has identified a massive number of uncharacterized
genes in
Arabidopsis thaliana and several other plant species.
To decipher these unknown
gene functions, several transient
expression
assays have been developed as rapid and convenient
alternatives to the lengthy creation of
transgenic plants. As
one of these transient
assays,
Agrobacterium-mediated transformation
harnesses the natural capability of
Agrobacterium to transfer
foreign
DNA into plant
cells with intact
cell walls. However,
pioneering applications of
Agrobacterium-based transient transformation
to
Arabidopsis have led to rather limited success with great
variability. In this protocol, we describe a Fast
Agrobacterium-mediated
Seedling Transformation (FAST)
technique for transient
gene expression
analysis in
Arabidopsis and other dicot or monocot
species. This
technique makes use of the cocultivation of young
plant seedlings with
Agrobacterium in the presence of the surfactant
Silwet L-77. The young seedlings can be grown easily and were
found to be more susceptible to
Agrobacterium transformation
compared with adult plants. The surfactant facilitates transformation
of plant
cells, thus replacing wounding or a device-dependent
vacuum step during plant transformation. This protocol provides
a quick, efficient, and economical
assay for
gene function in
intact plants with minimal manual handling and without the need
for a dedicated device.