Adult Refsum disease
Jan. 22, 2024
This is an image preview.
Start a Free Account
to view the full image.
-
Nearly 3,000 illustrations, including video clips of neurologic disorders.
-
Every article is reviewed by our esteemed Editorial Board for accuracy and currency.
-
Full spectrum of neurology in 1,200 comprehensive articles.
-
Listen to MedLink on the go with Audio versions of each article.
Stepwise modification of N-linked carbohydrate chain on lysosomal hydrolases in the Golgi
Starting at the lower left of the illustration, in the cis-Golgi network, GlcNAc-1-phosphotransferase phosphorylates selected mannose residues on lysosomal enzymes. In the process uridine diphosphate (UDP) is converted to uridine monophosphate (UMP). Then, N-acetylglucosamine (GlcNAc) is removed by the uncovering enzyme (UCE) in the trans-Golgi network (Rohrer J, Kornfeld R. Lysosomal hydrolase mannose 6-phosphate uncovering enzyme resides in the trans-Golgi network. Mol Biol Cell 2001;12(6):1623-31.)
The phosphorylated enzymes bind with the mannose 6-phosphate (M6P) receptor and are internalized to the endosome and finally enter the lysosomes. (Source: Khan SA, Tomatsu SC. Mucolipidoses overview: past, present, and future. Int J Mol Sci 2020;21(18):6812. Enlarged and edited by Douglas J Lanska MD MS MSPH to improve sharpness and contrast. Creative Commons Attribution [CC BY] license. http://creativecommons.org/licenses/by/4.0.)