Eukaryotic  gene regulation:
   cytoplasm.
<P>
<BR><LI> mRNA  degradation:  degradation of an mRNA in the cytoplasm limits
its lifespan.
Review 1:  <A ClAsS=MID Href="../../../med/Vid/Campbell8e/18_Animations/18_13mRNADegradation_A.swf" oNClick="popurlt('../../../../med/Vid/Campbell8e/18_Animations/18_13mRNADegradation_A.swf');txtcolor('euk-regulation_cytoplasm2','gray');return false;" Id=euk-regulation_cytoplasm2><iMg sRc="/images/shockwave.gif" aLt='' boRDer=0></A>
<BR><LI> Protein   processing:   many  proteins  are  activated  by  signal
molecules in transduction pathways.
<BR><LI> Protein  degradation:  proteasomes  degrade proteins at the end of
their useful lifespan.
Review 2:  <A ClAsS=MID Href="../../../med/Vid/Campbell8e/18_Animations/18_12ProteinDegradation_A.swf" oNClick="popurlt('../../../../med/Vid/Campbell8e/18_Animations/18_12ProteinDegradation_A.swf');txtcolor('euk-regulation_cytoplasm4','gray');return false;" Id=euk-regulation_cytoplasm4><iMg sRc="/images/shockwave.gif" aLt='' boRDer=0></A>
<P>
   Summary exercise:  <A ClAsS=ACT Href="http://media.pearsoncmg.com/bc/bc_campbell_biology_7/media/activities/load.html?19&amp;B" oNClick="popact('http://media.pearsoncmg.com/bc/bc_campbell_biology_7/media/activities/load.html?19&amp;B');txtcolor('euk-regulation_cytoplasm5','gray');return false;" Id=euk-regulation_cytoplasm5><iMg sRc="/images/tutorial.gif" aLt='' boRDer=0></A>