Cellular stress response
The unfolded protein response (UPR ) is a cellular stress response related to the endoplasmic reticulum (ER) stress.[ 1] It has been found to be conserved between mammalian species,[ 2] as well as yeast [ 1] [ 3] and worm organisms.
The UPR is activated in response to an accumulation of unfolded or misfolded proteins in the lumen of the endoplasmic reticulum. In this scenario, the UPR has three aims: initially to restore normal function of the cell by halting protein translation , degrading misfolded proteins, and activating the signaling pathways that lead to increasing the production of molecular chaperones involved in protein folding . If these objectives are not achieved within a certain time span or the disruption is prolonged, the UPR aims towards apoptosis .
Sustained overactivation of the UPR has been implicated in prion diseases as well as several other neurodegenerative diseases , and inhibiting the UPR could become a treatment for those diseases.[ 4] Diseases amenable to UPR inhibition include Creutzfeldt–Jakob disease , Alzheimer's disease , Parkinson's disease , and Huntington's disease .[ 5] [ 6]
^ a b Hetz C, Papa FR (January 2018). "The Unfolded Protein Response and Cell Fate Control" . Molecular Cell . 69 (2): 169–181. doi :10.1016/j.molcel.2017.06.017 . PMID 29107536 .
^ "Peter Walter's short talk: Unfolding the UPR" . Archived from the original on 2017-07-12. Retrieved 2013-10-24 .
^ Kannan M, Sivaprakasam C, Prinz WA, Nachiappan V (December 2016). "Endoplasmic reticulum stress affects the transport of phosphatidylethanolamine from mitochondria to the endoplasmic reticulum in S.cerevisiae" . Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids . 1861 (12 Pt A): 1959–1967. doi :10.1016/j.bbalip.2016.09.015 . PMC 6322925 . PMID 27678054 .
^ Moreno JA, Halliday M, Molloy C, Radford H, Verity N, Axten JM, et al. (October 2013). "Oral treatment targeting the unfolded protein response prevents neurodegeneration and clinical disease in prion-infected mice". Science Translational Medicine . 5 (206): 206ra138. doi :10.1126/scitranslmed.3006767 . PMID 24107777 . S2CID 25570626 .
^ Scheper W, Hoozemans JJ (September 2015). "The unfolded protein response in neurodegenerative diseases: a neuropathological perspective" . Acta Neuropathologica . 130 (3): 315–31. doi :10.1007/s00401-015-1462-8 . PMC 4541706 . PMID 26210990 .
^ Lakkaraju AK, Frontzek K, Lemes E, Herrmann U, Losa M, Marpakwar R, Aguzzi A (September 2021). "Loss of PIKfyve drives the spongiform degeneration in prion diseases" . EMBO Molecular Medicine . 13 (9): e14714. doi :10.15252/emmm.202114714 . PMC 8518562 . PMID 34291577 .