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For transcription to begin the gene needs to be
stimulated by transciptional factors. These move from
the cytoplasm into the nucleus.
Each transcriptional factor has a site that binds to a
specific region of DNA
When it binds it stimulates transcription
mRNA is then produced and translation into a
polypeptide occurs.
When the gene is not being expressed the site that
the transcriptional factor binds to is blocked by an
inhibitor molecule.
The inhibitor molecule prevents the transcriptional
factors from binding and thus prevents transcription
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One way which has been researched but you
do not have to necessarily know about is the
Lac Operon
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The example you have to know about is how
the effect oestrogen has on transcription.
Using figure 1 from page 214 and the
information on page 240 produce a flow
diagram of how oestrogen effect gene
transcription.
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http://www.nature.com/focus/rnai/animations/inde
x.html
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Watch the following animation and make notes, we
are going to watch it twice so do not panic!
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Read through the two articles about how Andrew Z.
Fire and Craig C. Mello were award the Nobel prize
for their work in discovering si-RNA
Task using you notes and the articles write a 5
minute speech explaining what si-RNA is, how it
works and its significance to medicine.
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Complete the application questions
from page 242 – 243
Start working on the exam style
questions on page 244 – 245 these
have to be completed for homework.