1. Oligosaccharyltransferasee glucosidase I and II glycosylates the first asparigine that crosses to the luminal side through sec61(alpha beta gamma).
2. A Hsp70 system acts as a ratchet composed of:
The J domain protein sec63 in a complex with sec61.
This stimulated the ATP ase activity of Hsp70 (bip).
Bip pulls in the nascent polypeptide as a result of the two being stimulated to bind by ErdJ.
3. The glycoslyated asparagine is recognised by calnexin and calreticulin after the nucleotide exchange factor bap causes bip to disengage from the protein. They are very simuler but calnexin is membrane bound.
4. The two chaperones recognise Erp57, which forms and breaks disulphide bonds, allowng correct disulphide bond formation
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