Andrew: I actually
operate on cells without killing them. Not many people seem to have the
patience do that. I've been able to do amputations of cells. I've been
able to pull on receptors. I've been able to remove chromosomes, organelles,
nuclei. And, I've been able to -
Jack:
Now, wait a minute youve been able to remove one gene?
Andrew: No! Remove
genes. Plural. Like whole genomes, half genomes, stretches of a chromosome
that sort of thing.
Jack:
To look at these things: what do you need?
Andrew: A microscope.
A very, very high-resolution microscope.
Jack:
Called?
Andrew: Well, it's
a Zeiss or a Nikon with a 630 x-objective.
Jack:
What does that mean?
Andrew: That means
that the amplification in size is approximately 2-3 thousand times when
it gets onto the computer monitor.
Jack:
When you remove these genes -
Andrew: It's the
micro-needle
Jack:
You said it was very, very, the width - ?
Andrew: Yeah, its
about a half a wavelength of visible light in diameter.
Jack:
Half a wavelength of light in diameter.
Andrew: Yeah, a wavelength
of light is about a micron. Visible light I should say, and then half
of that is about 500 nanometers.
Jack:
And with tensegrity you're saying that you pull somewhere and you feel
that integrity and tension, together.
Andrew: The integrity
and tension disseminate through the system. Other kinds of models which
explain the cell won't do that. Tensegrity is a contraction of tension
and integrity. There's tension throughout the system and its integrating.
Integrated tension. I've demonstrated that. That is the way the cytoskeletal
lattices are organized. There not organized according to the continual
mechanical models that most biophysicists still publish on and study.
Jack:
Many of your colleagues dont like tensegrity. Even if they agree
with your findings they dont see what the term adds to the studies
youve done, they dont think that its needed.
Andrew: No! They
think the cell is a water balloon, and they want to preserve their old
17th century thoughts Many people want to continue to look at the cell
as though its a big vessel of colloids [suspensions like particles floating
in a gel in a cell] running around bumping into each other, when in fact,
its not; its a highly- structured organization of protoplasm. One
would wager that almost every water molecule is tethered. Theres
very little free water in the cell, to have chemical reactions with. It
all migrates around these little fibers and that's why theyre studying
motors here at this meeting, to understand the cargo. Theyre tethered
to a railroad track, okay, they dont diffuse randomly. If they did,
it violates another the basic principles of fidelity and efficiency. The
times that reactions would take to icome to fruition would be enormous.
The responses of cells to a physical perturbation such as pulling on your
eyelid and watching it snap back would take forever if it were a water
balloon.
Jack:
It has lattices?
Andrew: It has lattices
in it that are connected in certain ways. Like that model I brought. [Maniotis
had used a model during his presentation]
Jack:
It keeps its structure? Protects it?
Andrew: What I believe
is, its there to maintain itself against change. Thats the reason
why clams have stayed the same for so many millions of years.
Jack: O.K. But you are able to turn your model inside out.
Andrew: Well, I've
done that. I've turned cells inside out. But the principle experiment
I'm talking about is just to pull on it, and to see if the response would
be that of a water balloon. And it's not. It has the response of that
funny model I brought.
Jack:
You also said it was also like a tent in a way.
Andrew: Yes, it's
tethered and it's interconnected by large posts and things like that.
So, if you tug on one area of it that force will be dissipated throughout
the whole structure. Rather than a continuum model, a balloon filled with
water or even molasses.
Jack:
But isn't it? Isn't the tension among cells all together just like the
tension created by packed masses of water balloons?
Andrew: Water can
act as a compression - resistant structure if its put in a balloon
or something like that. But, again youre confirming rather than
denying, because that's, that's not all that's in there. The water can
act as a compression resistance structure. Many cells have big vacuoles
in them filled with water, and that will act as a compression-resistant
struts, under continuous tension. What were talking about is not
the specific As, B's, and C's within the cell. Were trying
to generalize the forces which will describe the cell more accurately.
And that is through an integration of these ... they could be vacuoles,
they could be filaments, they could be other kinds of structures. But
the bottom line is that there is continuous tension in the system. And
it resists the force of that tension pulling it together by having one
or many forms of compression resistance. It may be the way it attaches
to the outside, because you can resist tension by nailing it like a tent
with these things so it won't implode, or collapse. Or you can have structures
on the inside, which are very firm, that don't bend very well like microtubules,
or vacuoles, or the nucleus, itself, or DNA - DNA is a wonderful tensgrity
structure in and of itself such that the modules within the cell are also
conforming to these principles.
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