ER stress response Flashcards
What is the smooth ER for?
steriod and glucose metabolism, conjugation and FA synthesis
What is rough ER for
protein synthesis
What is nascent protein ‘pathway’
translocation, glycosylation, chaperone-mediated folding
What is involved in CM protein folding>
correct folding domains, S-S bonds, peptidyl prolyl bond formation
What is role of BiP?
Binding protein to prevent premature folding of proteins (its an ATPase)
Where does S-S bonds occur?
between cysteine residues
What are PDIs?
protein disulfide isomerases - they help form the S-S bonds on the protein by intermediately forming one with the protein
What are the 2 parts in Quality control
ER-associated degradation and transport carrier sorting
What are the methods of ERAD?
deglycosylation, polyub’ing and degradation
What is the UPR?
unfolded protein response - when the ER is stressed
how is information transferred from ER to nucleus?
transmembrane sensor proteins
What are the three arms of the UPR?
IRE1, PERK and ATF6
how does the IRE1 and ATF6 arms of UPR work?
IRE1alpa can mediate decay of mRNA
How can UPR elicit apoptosis
ER releases Ca2+, IRE1 activates JNK, CHOP induced by PERK arm, GADD34 dephosphorylates eIF2alpha, Bcl2 is inhibited and Bax, Bak and Bim induced, and ER localised caspases are activated
What are some ER stress-inducing toxins
Ethanol, Gold NPs, TBT (tributyltin), Cadmium, Arsenite, Zearalenone, cigarette smoke, acrolein,
