A new technology has been developed in the
last few years that enables you to target
the genome exactly where you want with high
precision.
These tools, called TAL effector proteins
were originally identified as bacterial plant
pathogens.
In nature TAL proteins are delivered to the
plant host cell by the bacterium and are coded
to bind to the genomic DNA at certain promoter
elements, activating genes and facilitating
infection.
Based on this technology we have developed
a service that produces synthetically engineered
versions of TAL binding proteins that enable
you to target the genome exactly where you
want.
Let's have a detailed look at this:
The GeneArt Precision TAL effectors are made
up of two parts.
One part binds the DNA.
You can design that to recognize just about
any sequence you want.
This binding part consists of 18 or 24 repeat
modules.
Each repeat is responsible for binding a specific
base in the DNA and the repeats are not thought
to interfere with each other.
That allows us to engineer these molecules
to bind any stretch of the DNA that you desire.
To the DNA binding part we fuse a second part:
For example TALs with nuclease domains are
used to generate double-stranded breaks by
using two TAL effectors to each cleave a single
strand.
The space between the two individual TAL DNA
binding sites is an important parameter for
effective cleavage.
Usually, a spacer of about 15 bp works well.
With this technique you can create gene knock-outs.
The DNA ends formed by the clevage are repaired
by the cell, often leaving deletions or small
insertions.
In these cases, two thirds of the repair events
would alter the reading frame of a gene and
create a knock-out.
Another option is to insert DNA sequences
into the cut DNA.
This process uses small ares of homology in
the new 'donor' DNA to correct the DNA sequence
or insert new DNA sequences.
Ideally the insert sequence has overlapping
homologous sequences on each side of about
300 to 500 bp.
We also offer an activator domain to control
function of genes.
That allows you to introduce these molecules
into cells, whether it is a plant cell or
an animal cell, and activate a gene specifically
at the locus you want.
Additionally you can choose a repressor.
If you are looking at novel methods of genome
modification and regulation and want to use
your own effector you can choose the MCS vector
and insert a protein-coding sequence of interest
which allows you to create a TAL effector
of your choice.
Examples for applications in both plant and
animals can be; elucidating the basic function
and regulation of a gene, studying metabolic
pathways, embryonic stem cell research and
research on disease models.
It is a powerful way to edit genomes and control
gene function.
It's easy: Go to the TAL web page or into
the GeneArt online order portal.
Download the excel order form, fill in your
binding sequences and effector choice and
send the form to geneartsupport@lifetech.com
Within 2 weeks we will create a set of TAL
effectors that bind to your specific target.
The GeneArt Precision TALs are delivered it
to you as Gateway® entry clones, ready for
you to target the genome exactly where you
want.
