Endoplasmic Reticulum-Associated Degradation (ERAD) of Misfolded Glycoproteins and Mutant P23H Rhodopsin in Photoreceptor Cells

  • Heike Kroeger
  • Wei-Chieh Chiang
  • Jonathan H. LinEmail author
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 723)


Membrane proteins, such as rhodopsin, often undergo N-linked glycosylation after translocation into the endoplasmic reticulum (ER). N-linked glycans are markers for correct protein folding, protein quality control, transport, and recognition by the ER-associated degradation (ERAD) machinery. The ER contains many resident proteins that promote correct folding of newly synthesized proteins and prevent inappropriate aggregation of protein-folding intermediates. The quality control mechanisms of the ER guarantee that only correctly folded proteins exit the ER and progress through the secretory pathway. Here, we review the ERAD pathway for glycoproteins and discuss recent reports linking ERAD to the development of retinitis pigmentosa arising from misfolded rhodopsin.


Misfolded proteins ERAD ER Quality control P23H rhodopsin Photoreceptor cells 



We thank M. LaVail for helpful suggestions on this manuscript and grant support from the Hope for Vision Foundation, the Karl Kirchgessner Foundation, and the NIH (EY018313, EY020846). W.C. Chiang received postdoctoral support from the Fight-for-Sight Foundation.


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Heike Kroeger
    • 1
  • Wei-Chieh Chiang
    • 1
  • Jonathan H. Lin
    • 1
    Email author
  1. 1.Department of PathologyUniversity of California, San DiegoLa JollaUSA

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