N-acetylglucosamine-1-phosphotransferase subunits alpha/beta precursor (GNPTAB, GlcNAc-1-phosphotransferase alpha/beta, UDP-N-acetylglucosamine-1-phosphotransferase alpha/beta, stealth protein GNPTAB)

Function

• precursor to
  • N-acetylglucosamine-1-phosphotransferase alpha
  • N-acetylglucosamine-1-phosphotransferase beta
• which are components of N-acetylglucosamine-1-phosphotransferase
• the alpha- & beta-subunits appear to be generated by a proteolytic cleavage at the Lys-928-Asp-929 bond
• the alpha &/or beta subunit(s) are catalytic, the gamma subunit functions in recognition of lysosomal enzymes

Structure

• belongs to the stealth family
• contains 1 EF-hand domain
• contains 2 LNR (lin/notch) repeats

Alternative splicing

named isoforms=2

Expression

• expressed in the heart, brain, placenta, lung, liver, skeletal muscle, kidney, pancreas

Pathology

• defects in GNPTAB are the cause of mucolipidosis type 2 & 3

More general terms

• protein precursor
• enzyme catalytic subunit

More specific terms

• N-acetylglucosamine-1-phosphotransferase subunit alpha (GNPTA, GlcNAc-1-phosphotransferase alpha, UDP-N-acetylglucosamine-1-phosphotransferase alpha)
• N-acetylglucosamine-1-phosphotransferase subunits beta (GNPTB, GlcNAc-1-phosphotransferase beta, UDP-N-acetylglucosamine-1-phosphotransferase beta)

Additional terms

• mucolipidosis
• stealth protein

Database

• OMIM: https://mirror.omim.org/entry/252500
• OMIM: https://mirror.omim.org/entry/252600
• OMIM: https://mirror.omim.org/entry/607840
• UniProt: http://www.uniprot.org/uniprot/Q3T906.html