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Endoplasmic reticulum

The endoplasmic reticulum (ER) is an extensive three-dimensional network that stretches from the inner nuclear envelope to the cell cortex with a single, continuous membrane and a single, continuous lumen. The ER contains specialized regions that carry out unique functions.

Types

- smooth endoplasmic reticulum (SER)
- rough endoplasmic reticulum (RER)

Pathology

- endoplasmic reticulum stress

  • RNA translation diseases
    • Wolcott-Rallison syndrome

- endoplasmic reticulum retention

  • alpha1-anti-trypsin deficiency (alpha1AT deficiency) variants exhibit a selective defect in migration of this secretory protein from the endoplasmic reticulum (ER) to Golgi apparatus.
  • This is most marked for the PiZ polypeptide, attributable to a single amino acid substitution of Glu342 to Lys342. The mutant polypeptide (α1AT-Z) is abnormally folded, and polymerizes, causing its retention in the ER. All individuals with the PiZZ genotype accumulate α1AT-Z in the ER of hepatocytes.

See also

- cellular organelles
- reticulum endoplasmic stress
- ER protein transport

References

- Pizzo P, Pozzan T. Mitochondria-endoplasmic reticulum choreography: structure and signaling dynamics. Trends Cell Biol. 2007 Oct;17(10):511-7. PMID: #17851078#

- Zimmermann R, Muller L, Wullich B. Protein transport into the endoplasmic reticulum: mechanisms and pathologies. Trends Mol Med. 2006 Dec;12(12):567-73. PMID: #17071140#

- Federovitch CM, Ron D, Hampton RY. The dynamic ER: experimental approaches and current questions. Curr Opin Cell Biol. 2005 Aug;17(4):409-14. PMID: #15975777#

- Levine T, Rabouille C. Endoplasmic reticulum: one continuous network compartmentalized by extrinsic cues. Curr Opin Cell Biol. 2005 Aug;17(4):362-8. PMID: #15975783#

- Shi Y, Taylor SI, Tan SL, Sonenberg N. When translation meets metabolism: multiple links to diabetes. Endocr Rev. 2003 Feb;24(1):91-101. PMID: #12588811#

- Harding HP, Ron D. Endoplasmic reticulum stress and the development of diabetes: a review. Diabetes. 2002 Dec;51 Suppl 3:S455-61. PMID: #12475790#

- Drenth JP, Martina JA, van de Kerkhof R, Bonifacino JS, Jansen JB. Polycystic liver disease is a disorder of cotranslational protein processing. Trends Mol Med. 2005 Jan;11(1):37-42. PMID: #15649821#

- Hebert DN, Garman SC, Molinari M. The glycan code of the endoplasmic reticulum: asparagine-linked carbohydrates as protein maturation and quality-control tags. Trends Cell Biol. 2005 Jul;15(7):364-70. PMID: #15939591#

- Rao RV, Bredesen DE. Misfolded proteins, endoplasmic reticulum stress and neurodegeneration. Curr Opin Cell Biol. 2004 Dec;16(6):653-62. PMID: #15530777#

- Palmer KJ, Stephens DJ. Biogenesis of ER-to-Golgi transport carriers: complex roles of COPII in ER export. Trends Cell Biol. 2004 Feb;14(2):57-61. PMID: #15106609#

- Berridge MJ. The endoplasmic reticulum: a multifunctional signaling organelle. Cell Calcium. 2002 Nov-Dec;32(5-6):235-49. PMID: #12543086#

- Thinakaran G. Metabolism of presenilins. J Mol Neurosci. 2001 Oct;17(2):183-92. PMID: #11816791#

- Patil C, Walter P: Intracellular signaling from the endoplasmic reticulum to the nucleus: the unfolded protein response in yeast and mammals. Curr Opin Cell Biol 13:349, 2001.