Transcripts
DR. LINGWOOD:
But there's now some sort of
appreciation that that actually is not true.
This is a computer model of a very simple model
membrane. The orange bits are the head groups
of the lipid and the green is the lipid
structure, but the blue is water.
So this is a model of a
membrane that surrounds cells. And what I draw
your attention to is, in fact, in this model the
water is actually penetrating into the structure
here. Even some water molecules are found
inside the membrane. And these are sort of not
appreciated in science at the moment, not
appreciated as to how invasive the water is.
What that means is that the
molecules in here, which will be in Gb3, the
sugar sequence will be in here, are very much
prone to being affected by their environment.
Their environment is the intercalated water and
the lipid. So it's very dynamic, the membrane's
not straight line. It's an incredibly dynamic
situation on the cell's surface.
And when the toxin comes into
this area on the cell surface, it's seeing a
landscape of Gb3, if you like, where it's in
different environments. And the different
environments cause different presentations of Gb3,
and therefore, the toxin can bind or not bind,
can move, can bind and move and bind and not
move, can bind and move and internalize or not
internalize. So there's a vast number of
possibilities available to the toxin.
And these, then, will affect
whether the cell is killed.
So the fact of having the
receptor is one thing, but the dynamics of the
receptor-toxin interplay is a huge additional
complex interaction.
