Download Eukaryotic Gene Regulation

Turning On and Off Genes (Gene Regulation) in
Eukaryotes
 Conserves energy that the cell needs for other
processes
Areas of Gene Regulation:
 Pre-Transcriptional Control:
o More condensed DNA is not transcribed
(physical barrier) (Negative control)
 Transcriptional Control:
o Genes for one metabolic pathway not
grouped together
o Transcription factors (proteins) control gene
expression: must bind to promoter to build
initiation complex that RNA polymerase
binds to. (Negative control)
o Operator sequences exist to increase rate of
transcription. (Positive control)
 Post-transcriptional Control:
o No 3’ poly-A tail: mRNA can’t leave
nucleus (Negative control)
o No 5’ cap: cytoplasmic enzymes break down
mRNA quickly.(Negative control)
o Long 3’ poly-A tail: mRNA will last longer
in the cytoplasm & be translated more
(Positive control)
 Translational Control:
o Regulatory proteins can bind to mRNA,
blocking translation (Negative control)
 Post-Translational Control:
o Regulatory proteins
 don’t allow polypeptide to take correct
shape
 interfere with transport
o Negative control if polypeptide is broken
down before it can become a protein.