[3] COPI is a coatomer that coats the vesicles transporting proteins from the Golgi complex to the ER.
Before the COP I protein can coat vesicles on the Golgi membrane, it must interact with a small GTPase called ARF1 (ADP ribosylation factor).
[5][6] This activates ARF1, allowing it to insert an amphipathic alpha helix into the lipid bilayer of the Golgi complex.
[7] The most common sorting signals include the amino acid sequence KKXX or KDEL.
[8] COP II is a coatomer that coats the vesicles transporting proteins from the ER to the golgi complex.
[4] The first step in the COP II pathway is the recruitment of a small GTPase named Sar1 to the ER membrane.
[9] This activates the Sar1 protein, causing its amphipathic alpha helix to bind to the ER membrane.
[7] Newly made secretory proteins must pass through the ER and the golgi complex before they can leave the cell.
[12] Congenital Dyserythropoetic Anemia Type II is a very rare disease with only a few hundred cases worldwide.
[12] Treatment for the disease involves blood transfusions, iron therapy, and the removal of the spleen.