Figure 5.

Proposed model for the assembly and membrane processing of G₄ ChEs. G₄ AChE, G₄ BChE, and AChE–BChE G₄ hybrid molecules are assembled in ER where both AChE_T and BChE_T subunits have initial glycosylation. These G₄ complexes are subsequently transported to Golgi apparatus where the catalytic subunits can have further glycosylation, and finally anchored onto the plasma membrane. The AChE_T glycosylation mutant, in which the glycosylation is completely abolished, is still able to assembly with PRiMA and BChE_T to form G₄ AChE and G₄ hybrid. However, both of them are retained in ER, which possibly will be subjected to the degradation pathway.