Seroatlas · Human Serome Atlas

SPCS3

Signal peptidase complex subunit 3

Also known as: FLJ22649, PRO3567, SPC22/23, SPC3, SPCS3_HUMAN, YLR066W

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

Protein identityUniProt · HPA

UniProt accession: P61009
Gene: SPCS3
Ensembl: ENSG00000129128
Chromosome: 4
Canonical length: 180 aa
Protein class: Metabolic proteins, Predicted intracellular proteins

OverviewNCBI Gene

Involved in signal peptide processing and viral protein processing. Located in endoplasmic reticulum membrane. Part of signal peptidase complex. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

180 residues, UniProt reviewed canonical sequence.

>P61009|SPCS3
     1  MNTVLSRANS LFAFSLSVMA ALTFGCFITT AFKDRSVPVR LHVSRIMLKN VEDFTGPRER
    61  SDLGFITFDI TADLENIFDW NVKQLFLYLS AEYSTKNNAL NQVVLWDKIV LRGDNPKLLL
   121  KDMKTKYFFF DDGNGLKGNR NVTLTLSWNV VPNAGILPLV TGSGHVSVPF PDTYEITKSY

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SPCS3 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): 0.34
Highest tissue expression: 93 nTPM

Expression across tissuesHPA

Tissue

salivary gland: 93 nTPM
pancreas: 68 nTPM
bone marrow: 64 nTPM
thyroid gland: 58 nTPM
appendix: 48 nTPM
lymph node: 47 nTPM

Single-cell type

plasma cells: 825 nCPM
esophageal apical cells: 320 nCPM
extravillous trophoblasts: 269 nCPM
pancreatic acinar cells: 245 nCPM
salivary acinar cells: 243 nCPM
syncytiotrophoblasts: 233 nCPM

Immune cell

basophil: 43 nTPM
plasmacytoid DC: 23 nTPM
MAIT T-cell: 20 nTPM
intermediate monocyte: 19 nTPM
total PBMC: 19 nTPM
NK-cell: 17 nTPM

Brain region

midbrain: 56 nTPM
white matter: 46 nTPM
spinal cord: 40 nTPM
hypothalamus: 37 nTPM
cerebral cortex: 37 nTPM
thalamus: 35 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SPCS3.

Disease | ImmuneIEDB

Conditions an epitope on SPCS3 was assayed in.

human immunodeficiency virus infectious disease T cell

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): 0.53
gnomAD pLI: 0.82
gnomAD missense Z: 2.04
DepMap mean gene effect: -1.08
DepMap dependency class: common

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

Cellular components

Protein domainsUniProt · Pfam · InterPro

Signal peptidase complex subunit 3
Signal peptidase subunit

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of SPCS3 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 SPCS3 as an antibody target. Whether an autoantibody or antibody against SPCS3 could matter depends on whether native SPCS3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SPCS3 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 SPCS3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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