DNA as the Library of a Cell
Is it sure that the most important information of living
cells is stored in the DNA? DNA seems to be nothing more than an
inventory of useful proteins and a tool to create those proteins. Could
it be that more important operational know how of how these proteins
interact to build a living organism is actually located in the rest of
the cell? So that the rest of the cell is the most important inheritance,
whereas DNA merely takes care of the genetic variation?
Thanks for the question. What you say is a fair hypothesis and one that was
favoured for many years. I think that one should not underestimated the
importance of understanding the way the rest of the cell functions but the
fact appears to be that the DNA directs and controls the functioning of the
rest of the cell.
I can illustrate this with one experiment. If I take the nucleus out of one
cell and put it into a completely different cell the new cell will take on
the form and function of the cell that provided the nucleus, not the form
and function of the cell that provided the rest of the cell. This was first
done with an alga called Acetabularia and has since been done with many
other animals including a sheep called Dolly (you may have heard about her).
I hope this in helpful.
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Update: June 2012