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If transcription stops, genetic information is no longer transferred
into the different parts of the body. Since these are then no longer
renewed, the organism dies within a few days. This is what happens in
cases of poisoning by certain toadstools, like the death cap, since
the toxin stops the transcription process. Understanding of how
transcription works also has a fundamental medical importance.
Disturbances in the transcription process are involved in many human
illnesses such as cancer, heart disease and various kinds of
inflammation.
The capacity of stem cells to develop into different types of specific
cells with well-defined functions in different organs, is also linked
to how the transcription is regulated. Understanding more about the
transcription process is therefore important for the development of
different therapeutic applications of stem cells.
Forty-seven years ago, the then twelve-year-old Roger Kornberg came to
Stockholm to see his father, Arthur Kornberg, receive the Nobel Prize
in Physiology or Medicine (1959) for his studies of how genetic
information is transferred from one DNA-molecule to another. Kornberg
senior had described how genetic information is transferred from a
mother cell to its daughters. What Roger Kornberg himself has now done
is to describe how the genetic information is copied from DNA into
what is called messenger-RNA. The messenger-RNA carries the
information out of the cell nucleus so that it can be used to
construct the proteins.
Kornberg's contribution has culminated in his creation of detailed
crystallographic pictures describing the transcription apparatus in
full action in a eukaryotic cell. In his pictures (all of them created
since 2000) we can see the new RNA-strand gradually developing, as
well as the role of several other molecules necessary for the
transcription process. The pictures are so detailed that separate
atoms can be distinguished and this makes it possible to understand
the mechanisms of transcription and how it is regulated.
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