Seroatlas · Human Serome Atlas

ST6GAL1

Beta-galactoside alpha-2,6-sialyltransferase 1

Also known as: CDw75, SIAT1, SIAT1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P15907
Gene
ST6GAL1
Ensembl
ENSG00000073849
Chromosome
3
Canonical length
406 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins, Predicted secreted proteins
Secretome location
Secreted to blood
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene encodes a member of glycosyltransferase family 29. The encoded protein is a type II membrane protein that catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates. The protein, which is normally found in the Golgi but can be proteolytically processed to a soluble form, is involved in the generation of the cell-surface carbohydrate determinants and differentiation antigens HB-6, CD75, and CD76. This gene has been incorrectly referred to as CD75. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2017]

Canonical amino-acid sequenceUniProt

406 residues, UniProt reviewed canonical sequence.

>P15907|ST6GAL1
     1  MIHTNLKKKF SCCVLVFLLF AVICVWKEKK KGSYYDSFKL QTKEFQVLKS LGKLAMGSDS
    61  QSVSSSSTQD PHRGRQTLGS LRGLAKAKPE ASFQVWNKDS SSKNLIPRLQ KIWKNYLSMN
   121  KYKVSYKGPG PGIKFSAEAL RCHLRDHVNV SMVEVTDFPF NTSEWEGYLP KESIRTKAGP
   181  WGRCAVVSSA GSLKSSQLGR EIDDHDAVLR FNGAPTANFQ QDVGTKTTIR LMNSQLVTTE
   241  KRFLKDSLYN EGILIVWDPS VYHSDIPKWY QNPDYNFFNN YKTYRKLHPN QPFYILKPQM
   301  PWELWDILQE ISPEEIQPNP PSSGMLGIII MMTLCDQVDI YEFLPSKRKT DVCYYYQKFF
   361  DSACTMGAYH PLLYEKNLVK HLNQGTDEDI YLLGKATLPG FRTIHC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ST6GAL1 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
Secreted
Secreted
Yes
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.31
Highest tissue expression
464 nTPM

Expression across tissuesHPA

Tissue

  • liver: 464 nTPM
  • tonsil: 139 nTPM
  • lymph node: 95 nTPM
  • spleen: 64 nTPM
  • thymus: 62 nTPM
  • thyroid gland: 61 nTPM

Single-cell type

  • microglia: 2,268 nCPM
  • plasma cells: 1,276 nCPM
  • b-cells: 990 nCPM
  • renal collecting duct principal cells: 795 nCPM
  • hepatocytes: 695 nCPM
  • salivary duct cells: 573 nCPM

Immune cell

  • memory B-cell: 88 nTPM
  • naive B-cell: 84 nTPM
  • naive CD4 T-cell: 81 nTPM
  • total PBMC: 59 nTPM
  • naive CD8 T-cell: 59 nTPM
  • memory CD4 T-cell: 52 nTPM

Brain region

  • medulla oblongata: 109 nTPM
  • white matter: 107 nTPM
  • spinal cord: 99 nTPM
  • pons: 97 nTPM
  • thalamus: 88 nTPM
  • midbrain: 85 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)
0.57
gnomAD pLI
0.23
gnomAD missense Z
1.15
DepMap mean gene effect
0.1
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 ST6GAL1 as an antibody target. Whether an autoantibody or antibody against ST6GAL1 could matter depends on whether native ST6GAL1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ST6GAL1 is annotated as secreted, so native ST6GAL1 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label ST6GAL1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ST6GAL1. 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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