MHC Class I Processing

Folding assembly of MHC class 1 molecule takes place in the lumen of ER.Initially folding of Class1 alpha chain is aided by calnexin chaperone.
Partially folded chain is transferred to second chaperone calrecticulam,which further  aids   folding  the chain and association with beta 2-Microglobulin.
Other proteins Frp57 and tapasin associate with it.
Class I molecule binds with the TAP Transporter to form peptide Loading complex.
The peptides that bind to MHC class 1 proteins are geneated by Proteosomes.
In cytoplasm Proteasome generates peptide fragments which will bind to MHC class 1 Protein.
The proteasome degrades protein into shorter fragments within cytosol and transports it to ER by TAP transporter.
By the process of Peptide ending ,non-binding and unstable peptides are released from ER.
Peptides with stable affinity binds with MHC molecule form stable complex.
Final phase of folding MHC class 1 molecule takes place.
Disassociation of Peptide Holding Complex takes place.
Peptide loaded with MHC class 1 molecule exits from ER and Moves to Cell surface with help of Golgi apparatus.where its recognized by by Antigen Receptors of CD8 Tcells.

No comments:
Write comments
Recommended Posts × +