GALNT1 explained

Polypeptide N-acetylgalactosaminyltransferase 1 is an enzyme that in humans is encoded by the GALNT1 gene.^{[1] [2] [3]}

This gene encodes a member of the UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase (GalNAc-T) family of enzymes. GalNAc-Ts initiate mucin-type O-linked glycosylation in the Golgi apparatus by catalyzing the transfer of GalNAc to serine and threonine residues on target proteins. They are characterized by an N-terminal transmembrane domain, a stem region, a lumenal catalytic domain containing a GT1 motif and Gal/GalNAc transferase motif, and a C-terminal ricin/lectin-like domain. GalNAc-Ts have different, but overlapping, substrate specificities and patterns of expression. Transcript variants derived from this gene that utilize alternative polyA signals have been described in the literature.^[3]

Further reading

• Paulson JC, Colley KJ . Glycosyltransferases. Structure, localization, and control of cell type-specific glycosylation. . J. Biol. Chem. . 264 . 30 . 17615–8 . 1989 . 10.1016/S0021-9258(19)84610-0 . 2681181 . free .
• Bennett EP, Hassan H, Clausen H . cDNA cloning and expression of a novel human UDP-N-acetyl-alpha-D-galactosamine. Polypeptide N-acetylgalactosaminyltransferase, GalNAc-t3. . J. Biol. Chem. . 271 . 29 . 17006–12 . 1996 . 8663203 . 10.1074/jbc.271.29.17006 . free .
• Meurer JA, Naylor JM, Baker CA . cDNA cloning, expression, and chromosomal localization of a human UDP-GalNAc:polypeptide, N-acetylgalactosaminyltransferase. . J. Biochem. . 118 . 3 . 568–74 . 1996 . 8690719 . 10.1093/oxfordjournals.jbchem.a124947. etal.
• Meurer JA, Drong RF, Homa FL . Organization of a human UDP-GalNAc:polypeptide, N-acetylgalactosaminyltransferase gene and a related processed pseudogene. . Glycobiology . 6 . 2 . 231–41 . 1996 . 8727794 . 10.1093/glycob/6.2.231 . etal. free .
• Takai S, Hinoda Y, Adachi T . A human UDP-GalNAc: polypeptide, N-acetylgalactosaminyltransferase type 1 gene is located at the chromosomal region 18q12.1. . Hum. Genet. . 99 . 3 . 293–4 . 1997 . 9050910 . 10.1007/s004390050359 . 22965327 . etal.
• Wandall HH, Hassan H, Mirgorodskaya E . Substrate specificities of three members of the human UDP-N-acetyl-alpha-D-galactosamine:Polypeptide N-acetylgalactosaminyltransferase family, GalNAc-T1, -T2, and -T3. . J. Biol. Chem. . 272 . 38 . 23503–14 . 1997 . 9295285 . 10.1074/jbc.272.38.23503 . etal. free .
• Müller S, Goletz S, Packer N . Localization of O-glycosylation sites on glycopeptide fragments from lactation-associated MUC1. All putative sites within the tandem repeat are glycosylation targets in vivo. . J. Biol. Chem. . 272 . 40 . 24780–93 . 1997 . 9312074 . 10.1074/jbc.272.40.24780 . etal. free .
• Röttger S, White J, Wandall HH . Localization of three human polypeptide GalNAc-transferases in HeLa cells suggests initiation of O-linked glycosylation throughout the Golgi apparatus. . J. Cell Sci. . 111 . 1. 45–60 . 1998 . 10.1242/jcs.111.1.45 . 9394011 . etal.
• Bennett EP, Weghuis DO, Merkx G . Genomic organization and chromosomal localization of three members of the UDP-N-acetylgalactosamine: polypeptide N-acetylgalactosaminyltransferase family. . Glycobiology . 8 . 6 . 547–55 . 1998 . 9592121 . 10.1093/glycob/8.6.547 . etal. free .
• Toward a complete human genome sequence. . Genome Res. . 8 . 11 . 1097–108 . 1999 . 9847074 . 10.1101/gr.8.11.1097. Sanger Centre . The . Washington University Genome Sequencing Cente . The . free .
• Tenno M, Saeki A, Kézdy FJ . The lectin domain of UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 1 is involved in O-glycosylation of a polypeptide with multiple acceptor sites. . J. Biol. Chem. . 277 . 49 . 47088–96 . 2003 . 12364335 . 10.1074/jbc.M207369200 . etal. free .
• Strausberg RL, Feingold EA, Grouse LH . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences. . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . 2002PNAS...9916899M . etal. free .
• Kinarsky L, Suryanarayanan G, Prakash O . Conformational studies on the MUC1 tandem repeat glycopeptides: implication for the enzymatic O-glycosylation of the mucin protein core. . Glycobiology . 13 . 12 . 929–39 . 2004 . 12925576 . 10.1093/glycob/cwg109 . etal. free .
• Brokx RD, Revers L, Zhang Q . Nuclear magnetic resonance-based dissection of a glycosyltransferase specificity for the mucin MUC1 tandem repeat. . Biochemistry . 42 . 47 . 13817–25 . 2004 . 14636048 . 10.1021/bi0353070 . etal. 10.1.1.879.1929 .
• Gerhard DS, Wagner L, Feingold EA . The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). . Genome Res. . 14 . 10B . 2121–7 . 2004 . 15489334 . 10.1101/gr.2596504 . 528928 . etal.

Notes and References

1. White T, Bennett EP, Takio K, Sorensen T, Bonding N, Clausen H . Purification and cDNA cloning of a human UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase . J Biol Chem . 270 . 41 . 24156–65 . Dec 1995 . 7592619 . 10.1074/jbc.270.41.24156 . free .
2. Tenno M, Toba S, Kezdy FJ, Elhammer AP, Kurosaka A . Identification of two cysteine residues involved in the binding of UDP-GalNAc to UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 1 (GalNAc-T1) . Eur J Biochem . 269 . 17 . 4308–16 . Aug 2002 . 12199709 . 10.1046/j.1432-1033.2002.03123.x . free .
3. Web site: Entrez Gene: GALNT1 UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 1 (GalNAc-T1).