0:00
My name is Zoltan Ivics.
I work at the Division of
Medical Biotechnology at the Paul
Ehrlich Institute
in Langen, Germany.
And the subject of this presentation
will be how we turn genomic junk
into treasure, an introduction
to transposable elements,
and how we use these transposons,
namely the Sleeping Beauty system,
for genetic engineering in
animals, and for molecular therapy.
0:29
Just to introduce to
you how transposons work
I'd like to outline the
so-called Cut-and-paste
DNA transposition mechanism.
The transposable element,
or transposon in short,
is depicted here on
the top of this slide.
The very ends of the transposon
are indicated as black arrows.
These are the so-called terminal
inverted repeats of the transposon.
These sequence are important for
the transpositional reaction.
And these repeats flank
in the natural context
a gene that encodes the
transposase protein, which
is the enzymatic factor of
the transpositional process.
So for transposition to occur the
transposase needs to be expressed,
followed by sequence
specific binding
of the transposase molecules to
the very ends of the transposon.
And then this is followed by
a so-called synaptic complex
formation, in which the two ends
of the transposable elements
are grouped together by
transposase interactions.
And then this step is
followed by physically removal
of the transposon out of
its original DNA context.
This is called transposon excision.
And then this excised transposon
will interact with a new piece
of DNA that is highlighted
here by the green color.
And the transposon will
integrate into this new DNA,
giving rise to a relocated
or transposed piece of DNA.
So transposition now occurs from
the yellow DNA into the green DNA,
and then the transpositional
reaction, the excisions that
generates damage, double
stranded DNA breaks
at the ends of the
transposon, which will be
repaired by host DNA
repair mechanisms.
