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Quality control in the endoplasmic reticulum protein factory


The endoplasmic reticulum (ER) is a factory where secretory proteins are manufactured, and where stringent quality-control systems ensure that only correctly folded proteins are sent to their final destinations. The changing needs of the ER factory are monitored by integrated signalling pathways that constantly adjust the levels of folding assistants. ER chaperones and signalling molecules are emerging as drug targets in amyloidoses and other protein-conformational diseases.

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Figure 1: Folding in the crowded environment of the ER.
Figure 2: The ER is not always that rough.


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We thank members of our laboratories for their criticisms and enthusiasm, D. Ron for helpful suggestions, T. Mastrandrea for secretarial assistance, and Associazione Italiana per la Ricerca sul Cancro (AIRC), Italian Ministries of Health, Education and Research (CoFin and Center of Excellence in Physiopathology of Cell Differentiation), NWO and Telethon for financial support. We apologize to the many colleagues whose seminal work we could not cite because of space limitations.

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Sitia, R., Braakman, I. Quality control in the endoplasmic reticulum protein factory. Nature 426, 891–894 (2003).

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