N-acetylglucosamine-1-phosphate transferase

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N-acetylglucosamine-1-phosphate transferase, alpha and beta subunits
Alt. symbols GNPTA
Entrez 79158
HUGO 29670
OMIM 607840
RefSeq NM_024312
UniProt Q3T906
Other data
Locus Chr. 12 q23.3
N-acetylglucosamine-1-phosphate transferase, gamma subunit
Symbol GNPTG
Alt. symbols GNPTAG
Entrez 84572
HUGO 23026
OMIM 607838
RefSeq NM_032520
UniProt Q9UJJ9
Other data
Locus Chr. 16 p13.3

N-acetylglucosamine-1-phosphate transferase is a transferase enzyme.


It is made up of two alpha (α), two beta (β), and two gamma (γ) subunits. GNPTAB produces the alpha and beta subunits. GlcNAc-1-phosphotransferase functions to prepare newly made enzymes for lysosome transportation (lysosomal hydrolases to the lysosome). Lysosomes, a part of an animal cells, helps break down large molecules into smaller ones that can be reused. GlcNAc-1-phosphotransferase catalyzes the N-linked glycosylation of asparagine residues with a molecule called mannose-6-phosphate (M6P). M6P acts as indicator whether a hydrolase should be transported to the lysosome or not. Once a hydrolase has the indication from an M6P, it can be transported to a lysosome. Surprisingly some lyosomal enzyme are only tagged at a rate of 5% or lower.

Clinical significance[edit]

It is associated with the following conditions:[1][2]

In melanocytic cells GNPTG gene expression may be regulated by MITF.[3]


  1. ^ Online Mendelian Inheritance in Man (OMIM) MUCOLIPIDOSIS II ALPHA/BETA -252500
  2. ^ Online Mendelian Inheritance in Man (OMIM) MUCOLIPIDOSIS III GAMMA -252605
  3. ^ Hoek KS, Schlegel NC, Eichhoff OM, et al. (2008). "Novel MITF targets identified using a two-step DNA microarray strategy". Pigment Cell Melanoma Res. 21 (6): 665–76. PMID 19067971. doi:10.1111/j.1755-148X.2008.00505.x. 

Kang, C., Riazuddin, S., Mundorff, J., Krasnewich, D., Friedman, P., Mullikin, J.C., and Drayna, D. (2010). Mutations in the Lysosomal Enzyme–Targeting Pathway and Persistent Stuttering. New England Journal of Medicine 362, 677-685.

External links[edit]