Seroatlas · Human Serome Atlas

IGSF5

Immunoglobulin superfamily member 5

Also known as: IGSF5_HUMAN, JAM4

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

Protein identityUniProt · HPA

UniProt accession: Q9NSI5
Gene: IGSF5
Ensembl: ENSG00000183067
Chromosome: 21
Canonical length: 407 aa
Protein class: Predicted membrane proteins
Subcellular location: Focal adhesion sites

OverviewNCBI Gene

Predicted to enable PDZ domain binding activity. Predicted to be involved in cell-cell adhesion. Predicted to be located in apical plasma membrane. Predicted to be active in bicellular tight junction and cell surface. [provided by Alliance of Genome Resources, Apr 2025]

Canonical amino-acid sequenceUniProt

407 residues, UniProt reviewed canonical sequence.

>Q9NSI5|IGSF5
     1  MGQKERSTAD TLPDLEEWKS AAGLRWWQTA VVDGSGSGNE VIEGPQNARV LKGSQARFNC
    61  TVSQGWKLIM WALSDMVVLS VRPMEPIITN DRFTSQRYDQ GGNFTSEMII HNVEPSDSGN
   121  IRCSLQNSRL HGSAYLTVQV MGELFIPSVN LVVAENEPCE VTCLPSHWTR LPDISWELGL
   181  LVSHSSYYFV PEPSDLQSAV SILALTPQSN GTLTCVATWK SLKARKSATV NLTVIRCPQD
   241  TGGGINIPGV LSSLPSLGFS LPTWGKVGLG LAGTMLLTPT CTLTIRCCCC RRRCCGCNCC
   301  CRCCFCCRRK RGFRIQFQKK SEKEKTNKET ETESGNENSG YNSDEQKTTD TASLPPKSCE
   361  SSDPEQRNSS CGPPHQRADQ RPPRPASHPQ ASFNLASPEK VSNTTVV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against IGSF5 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: Cell surface
Secreted: No
Transmembrane segments: 1
Mean surface accessibility (rSASA): 0.52
Highest tissue expression: 2.8 nTPM

Expression across tissuesHPA

Tissue

heart muscle: 2.8 nTPM
placenta: 2.2 nTPM
choroid plexus: 1.9 nTPM
epididymis: 1.8 nTPM
prostate: 1.3 nTPM
pancreas: 1.2 nTPM

Single-cell type

syncytiotrophoblasts: 305 nCPM
pituitary stem cells: 28 nCPM
brain inhibitory neurons: 24 nCPM
early spermatids: 15 nCPM
late primary spermatocytes: 14 nCPM
choroid plexus epithelial cells: 12 nCPM

Immune cell

neutrophil: 0.4 nTPM
basophil: 0.1 nTPM
classical monocyte: 0 nTPM
eosinophil: 0 nTPM
gdT-cell: 0 nTPM
intermediate monocyte: 0 nTPM

Brain region

hypothalamus: 15 nTPM
basal ganglia: 13 nTPM
choroid plexus: 12 nTPM
midbrain: 11 nTPM
thalamus: 11 nTPM
medulla oblongata: 11 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): 1.68
gnomAD pLI: 0
gnomAD missense Z: 0.25
DepMap mean gene effect: 0.02
DepMap dependency class: none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

cell-cell adhesion

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of IGSF5 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

MAGI1

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads IGSF5 as an antibody target. Whether an autoantibody or antibody against IGSF5 could matter depends on whether native IGSF5 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

IGSF5 is annotated at the cell surface, where native IGSF5 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label IGSF5 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...