Transcripts
DR. LINGWOOD:
And what is happening to the
Gb3, it's really very interesting. So this is
now a TLC overlay, and this band here is the
toxin binding to Gb3. And this is how we
visualize it.
I won't go into the details,
but so lane two is the Gb3 from the cell which
is not very sensitive to verotoxin. And the Gb3
binding you see is one band here and a slight
band underneath, in lane three is the cell which
is highly sensitive to verotoxin and targets the
toxin to the nucleus. And what you can see is, again, it
has this Gb3 band up high, but there is
more of this lower band.
Now, the TLC is actually
separating the Gb3 according to its lipid
structure. What this means is this kind of Gb3 has
a different lipid structure than this one, and
if you treat these cells in lane two with sodium
butyrate they become more sensitive. They now
target the toxin to the endoplasmic reticulum and
the nucleus.
And now you see this lower
band, which has a different lipid structure --
it has shorter fatty acid chains. The longer
chain species are in the upper band and shorter
chain species in the lower band. So the shorter
chain structures are increased by treating the
cells with sodium butyrate. Change in sensitivity
to verotoxin is increased by about a
thousand times.
So now what we're saying then
is that the lipid structure of the Gb3 not only
changes the binding, I've shown you that before,
but it actually changes the routing of the
toxin/Gb3 complex inside the cell. These cells
targeted to the Golgi. These two here targeted
to the endoplasmic reticulum in the nucleus. So
that's summarized just the same as I showed you
before.
