Seroatlas · Human Serome Atlas

BLOC1S3

Biogenesis of lysosome-related organelles complex 1 subunit 3

Also known as: BL1S3_HUMAN, BLOS3, HPS8

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

Protein identityUniProt · HPA

UniProt accession
Q6QNY0
Gene
BLOC1S3
Ensembl
ENSG00000189114
Chromosome
19
Canonical length
202 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Golgi apparatus

OverviewNCBI Gene

This gene encodes a protein that is a component of the BLOC1 multi-subunit protein complex. This complex is necessary for the biogenesis of specialized organelles of the endosomal-lysosomal system, including platelet dense granules and melanosomes. Mutations in this gene cause Hermansky-Pudlak syndrome 8, a disease characterized by lysosomal storage defects, bleeding due to platelet storage pool deficiency, and oculocutaneous albinism. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

202 residues, UniProt reviewed canonical sequence.

>Q6QNY0|BLOC1S3
     1  MASQGRRRRP LRRPETVVPG EATETDSERS ASSSEEEELY LGPSGPTRGR PTGLRVAGEA
    61  AETDSEPEPE PEPTAAPRDL PPLVVQRESA EEAWGTEEAP APAPARSLLQ LRLAESQARL
   121  DHDVAAAVSG VYRRAGRDVA ALASRLAAAQ AAGLAAAHSV RLARGDLCAL AERLDIVAGC
   181  RLLPDIRGVP GTEPEKDPGP RA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against BLOC1S3 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.65
Highest tissue expression
13 nTPM

Expression across tissuesHPA

Tissue

  • skin: 13 nTPM
  • bone marrow: 12 nTPM
  • spleen: 11 nTPM
  • liver: 7.6 nTPM
  • cerebral cortex: 7.3 nTPM
  • stomach: 7.2 nTPM

Single-cell type

  • late spermatids: 96 nCPM
  • early spermatids: 9.6 nCPM
  • erythrocyte progenitors: 0.4 nCPM
  • neutrophils: 0.4 nCPM
  • basal prostatic cells: 0.3 nCPM
  • leydig cells: 0.3 nCPM

Immune cell

  • basophil: 52 nTPM
  • intermediate monocyte: 43 nTPM
  • non-classical monocyte: 40 nTPM
  • gdT-cell: 38 nTPM
  • neutrophil: 35 nTPM
  • classical monocyte: 35 nTPM

Brain region

  • medulla oblongata: 21 nTPM
  • white matter: 20 nTPM
  • pons: 19 nTPM
  • cerebral cortex: 18 nTPM
  • midbrain: 18 nTPM
  • thalamus: 18 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about BLOC1S3.

Disease | AllUniProt

Conditions BLOC1S3 is implicated in, by any mechanism.

Disease | GeneticClinVar

5 pathogenic / likely-pathogenic of 207 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Hermansky-Pudlak syndrome 8

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)
1.91
gnomAD pLI
0
gnomAD missense Z
-0.33
DepMap mean gene effect
-0.1
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 7% 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

  • BLOC-1 complex, subunit 3
  • Biogenesis of lysosome-related organelles complex 1 subunit 3

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of BLOC1S3 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 BLOC1S3 as an antibody target. Whether an autoantibody or antibody against BLOC1S3 could matter depends on whether native BLOC1S3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

BLOC1S3 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 BLOC1S3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/BLOC1S3. 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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