Seroatlas · Human Serome Atlas

GALNT9

Polypeptide N-acetylgalactosaminyltransferase 9

Also known as: GALNAC-T9, GALT9_HUMAN

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q9HCQ5
Gene
GALNT9
Ensembl
ENSG00000182870
Chromosome
12
Canonical length
603 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Vesicles

OverviewNCBI Gene

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. This gene is expressed specifically in the brain, with highest expression in the cerebellum. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

603 residues, UniProt reviewed canonical sequence.

>Q9HCQ5|GALNT9
     1  MAVARKIRTL LTVNILVFVG IVLFSVYCRL QGRSQELVRI VSGDRRVRSR HAKVGTLGDR
    61  EAILQRLDHL EEVVYNQLNG LAKPIGLVEG PGGLGQGGLA ATLRDDGQEA EGKYEEYGYN
   121  AQLSDRISLD RSIPDYRPRK CRQMSYAQDL PQVSVVFIFV NEALSVILRS VHSVVNHTPS
   181  QLLKEVILVD DNSDNVELKF NLDQYVNKRY PGLVKIVRNS RREGLIRARL QGWKAATAPV
   241  VGFFDAHVEF NTGWAEPALS RIREDRRRIV LPAIDNIKYS TFEVQQYANA AHGYNWGLRC
   301  MYIIPPQDWL DRGDESAPIR TPAMIGCSFV VDREYFGDIG LLDPGMEVYG GENVELGMRV
   361  WQCGGSMEVL PCSRVAHIER TRKPYNNDID YYAKRNALRA AEVWMDDFKS HVYMAWNIPM
   421  SNPGVDFGDV SERLALRQRL KCRSFKWYLE NVYPEMRVYN NTLTYGEVRN SKASAYCLDQ
   481  GAEDGDRAIL YPCHGMSSQL VRYSADGLLQ LGPLGSTAFL PDSKCLVDDG TGRMPTLKKC
   541  EDVARPTQRL WDFTQSGPIV SRATGRCLEV EMSKDANFGL RLVVQRCSGQ KWMIRNWIKH
   601  ARH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against GALNT9 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.27
Highest tissue expression
128 nTPM

Expression across tissuesHPA

Tissue

  • cerebellum: 128 nTPM
  • cerebral cortex: 57 nTPM
  • hippocampal formation: 38 nTPM
  • amygdala: 27 nTPM
  • hypothalamus: 17 nTPM
  • thyroid gland: 12 nTPM

Single-cell type

  • brain excitatory neurons: 60 nCPM
  • loop of henle epithelial cells: 30 nCPM
  • other brain neurons: 17 nCPM
  • brain inhibitory neurons: 12 nCPM
  • renal collecting duct principal cells: 8.3 nCPM
  • bergmann glia: 8.2 nCPM

Immune cell

  • memory B-cell: 0.2 nTPM
  • naive B-cell: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM

Brain region

  • cerebral cortex: 56 nTPM
  • cerebellum: 49 nTPM
  • white matter: 31 nTPM
  • hippocampal formation: 31 nTPM
  • thalamus: 28 nTPM
  • basal ganglia: 25 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.07
gnomAD pLI
0.01
gnomAD missense Z
0.33
DepMap mean gene effect
-0.06
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads GALNT9 as an antibody target. Whether an autoantibody or antibody against GALNT9 could matter depends on whether native GALNT9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

GALNT9 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label GALNT9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/GALNT9. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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