File:Chaperones.png

Original file(4,081 × 3,391 pixels, file size: 591 KB, MIME type: image/png)

Summary

Description
English: (Caption taken from Frucstaci et al, 2001[1]) "Panel A shows the processing of normal α-galactosidase A. Newly synthesized α-galactosidase A is translocated into the endoplasmic reticulum, where molecular chaperones facilitate its proper folding and dimerization by specialized processing enzymes. The molecular chaperones then dissociate from the folded, dimerized enzyme, which moves to the Golgi apparatus and then to lysosomes, where the enzyme is stable and active in the acidic environment of these organelles. Panel B shows the processing of mutant α-galactosidase A. Most mutations in the α-galactosidase A gene encode α-galactosidase A molecules that are misfolded, misassembled, or aggregated in the endoplasmic reticulum, where they are degraded, presumably by the ubiquitin–proteasome pathway. However, certain missense mutations decrease the stability of the enzyme, but the conformation of the active site is retained. Most of this type of mutant enzyme is degraded in the endoplasmic reticulum. However, these mutant forms of α-galactosidase A may be stabilized by chemical chaperones, such as galactose, that bind to the active site of the enzyme, promote folding, and stabilize the mutant enzyme. Some of the enzyme then reaches the lysosomes, where it retains low levels of activity. In the lysosomes, the accumulated glycosphingolipid substrates displace the chemical chaperones and are hydrolyzed by the enzyme. Modified from Kuznetsov and Nigam[2]"
Date
Source doi:10.1056/nejm200107053450104
Author Frustaci A, Chimenti C, Ricci R, Natale L, Russo MA, Pieroni M, Eng CM, Desnick RJ

Licensing

w:en:Creative Commons
attribution share alike
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
  • share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.

Captions

Mode of action of chaperones

Items portrayed in this file

depicts

14 March 2019

image/png

e2da2c9055e1436fcb185f40626d5493d46730ef

604,672 byte

3,391 pixel

4,081 pixel

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current18:58, 14 March 2019Thumbnail for version as of 18:58, 14 March 20194,081 × 3,391 (591 KB)Uahc1User created page with UploadWizard
The following pages on the English Wikipedia use this file (pages on other projects are not listed):

Metadata