POST TRANSLATION
MODIFICATION
SO AFTER TRANSLATION…..
• Where is the polypeptide chain located?
PROTEIN FOLDING
• Folding occurs with the help of chaperone proteins,
also called heat shock proteins
PROTEIN FOLDING
• Folding occurs either during translation called co
translation folding
• Can also occur after translation
during post translational
folding
IMPROPER FOLDING
• Proper folding is very important!
• Why?
• What diseases come from misfolded proteins?
IMPROPER FOLDING
• Misfolded proteins are either degraded in the cytoplasm
or move to the lysosome to be degraded
• Either way, proteases, a type of enzyme, assist in
breaking down misfolded proteins
PROPERLY FOLDED PROTEINS
• Properly folded proteins undergo what is called posttranslation modification
• The first step is to move the proteins to the Golgi
PROPERLY FOLDED PROTEINS
• So what exactly happens in the Golgi?
• Further protein folding
• What protein is used to help?
• What happens to misfolded proteins?
• Cleavage
• Proteases used again
OTHER GOLGI MODIFICATIONS
• Phosphorylation
• Glycosylation
• Ubiquitination