Seroatlas · Human Serome Atlas

AUP1

Lipid droplet-regulating VLDL assembly factor AUP1

Also known as: AUP1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9Y679
Gene
AUP1
Ensembl
ENSG00000115307
Chromosome
2
Canonical length
410 aa
Protein class
Predicted membrane proteins
Subcellular location
Nucleoplasm,Vesicles

OverviewNCBI Gene

The protein encoded this gene is involved in several pathways including quality control of misfolded proteins in the endoplasmic reticulum and lipid droplet accumulation. Lipid droplets are organelles in the cytoplasm that store neutral lipids such as cholesterol esters and trigylycerides to prevent the overabundance of free cholesterol and fatty acids in cells, but also to act as storage for other metabolic processes, such as membrane biogenesis. Reduced expression of this gene results in reduced lipid droplet clustering, a function that is dependent on ubiquitination of the protein. This protein contains multiple domains including a hydrophobic N-terminal domain, an acetyltranferase domain, a ubiquitin-binding CUE domain, and a UBE2B2-binding domain (G2BR). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2014]

Canonical amino-acid sequenceUniProt

410 residues, UniProt reviewed canonical sequence.

>Q9Y679|AUP1
     1  MELPSGPGPE RLFDSHRLPG DCFLLLVLLL YAPVGFCLLV LRLFLGIHVF LVSCALPDSV
    61  LRRFVVRTMC AVLGLVARQE DSGLRDHSVR VLISNHVTPF DHNIVNLLTT CSTPLLNSPP
   121  SFVCWSRGFM EMNGRGELVE SLKRFCASTR LPPTPLLLFP EEEATNGREG LLRFSSWPFS
   181  IQDVVQPLTL QVQRPLVSVT VSDASWVSEL LWSLFVPFTV YQVRWLRPVH RQLGEANEEF
   241  ALRVQQLVAK ELGQTGTRLT PADKAEHMKR QRHPRLRPQS AQSSFPPSPG PSPDVQLATL
   301  AQRVKEVLPH VPLGVIQRDL AKTGCVDLTI TNLLEGAVAF MPEDITKGTQ SLPTASASKF
   361  PSSGPVTPQP TALTFAKSSW ARQESLQERK QALYEYARRR FTERRAQEAD

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against AUP1 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
0
Mean surface accessibility (rSASA)
0.36
Highest tissue expression
125 nTPM

Expression across tissuesHPA

Tissue

  • pancreas: 125 nTPM
  • liver: 100 nTPM
  • choroid plexus: 97 nTPM
  • skeletal muscle: 97 nTPM
  • salivary gland: 84 nTPM
  • stomach: 80 nTPM

Single-cell type

  • extravillous trophoblasts: 279 nCPM
  • syncytiotrophoblasts: 265 nCPM
  • esophageal apical cells: 264 nCPM
  • esophageal suprabasal cells: 224 nCPM
  • migrating cytotrophoblasts: 205 nCPM
  • esophageal basal cells: 181 nCPM

Immune cell

  • intermediate monocyte: 170 nTPM
  • non-classical monocyte: 145 nTPM
  • classical monocyte: 133 nTPM
  • total PBMC: 132 nTPM
  • myeloid DC: 125 nTPM
  • plasmacytoid DC: 119 nTPM

Brain region

  • medulla oblongata: 38 nTPM
  • choroid plexus: 35 nTPM
  • white matter: 35 nTPM
  • hypothalamus: 34 nTPM
  • cerebellum: 33 nTPM
  • spinal cord: 32 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)
0.76
gnomAD pLI
0
gnomAD missense Z
0.59
DepMap mean gene effect
-0.21
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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

InteractionsUniProt · HPA

Protein binding partners of AUP1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads AUP1 as an antibody target. Whether an autoantibody or antibody against AUP1 could matter depends on whether native AUP1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

AUP1 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 AUP1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/AUP1. 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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