Quality control and protein folding in the secretory pathway.

摘要: The biosynthesis of secretory and membrane proteins in the endoplasmic reticulum (ER) yields mostly properly folded assembled structures with full biological activity. Such fidelity is maintained by quality control (QC) mechanisms that avoid production nonnative structures. QC relies on chaperone systems ER monitor assist folding process. When promotion not sufficient, are retained eventually retranslocated to cytosol for degradation ubiquitin proteasome pathway. Retention fail can sometimes occur beyond ER, take place lysosomes. Several diseases associated do pass QC, be degraded efficiently, accumulate as aggregates. In other cases, pathology arises from downregulation mutated but potentially functional system.