Seroatlas · Human Serome Atlas

CIB4

Calcium and integrin-binding family member 4

Also known as: CIB4_HUMAN

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

Protein identityUniProt · HPA

UniProt accession: A0PJX0
Gene: CIB4
Ensembl: ENSG00000157884
Chromosome: 2
Canonical length: 185 aa
Protein class: Predicted intracellular proteins

OverviewNCBI Gene

Enables calcium ion binding activity and magnesium ion binding activity. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

185 residues, UniProt reviewed canonical sequence.

>A0PJX0|CIB4
     1  MGQCLRYQMH WEDLEEYQAL TFLTRNEILC IHDTFLKLCP PGKYYKEATL TMDQVSSLPA
    61  LRVNPFRDRI CRVFSHKGMF SFEDVLGMAS VFSEQACPSL KIEYAFRIYD FNENGFIDEE
   121  DLQRIILRLL NSDDMSEDLL MDLTNHVLSE SDLDNDNMLS FSEFEHAMAK SPDFMNSFRI
   181  HFWGC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CIB4 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: Unknown
Secreted: No
Transmembrane segments: 0
Mean surface accessibility (rSASA): 0.3
Highest tissue expression: 17 nTPM

Expression across tissuesHPA

Tissue

testis: 17 nTPM
thyroid gland: 2.3 nTPM
choroid plexus: 0.9 nTPM
adrenal gland: 0.7 nTPM
placenta: 0.7 nTPM
prostate: 0.3 nTPM

Single-cell type

late primary spermatocytes: 198 nCPM
early spermatids: 143 nCPM
adrenal cortex cells: 82 nCPM
late spermatids: 20 nCPM
pancreatic acinar cells: 13 nCPM
renal collecting duct principal cells: 9.7 nCPM

Immune cell

basophil: 0 nTPM
classical monocyte: 0 nTPM
eosinophil: 0 nTPM
gdT-cell: 0 nTPM
intermediate monocyte: 0 nTPM
MAIT T-cell: 0 nTPM

Brain region

pons: 2 nTPM
choroid plexus: 1.6 nTPM
cerebellum: 1.3 nTPM
medulla oblongata: 1.2 nTPM
midbrain: 1.2 nTPM
hypothalamus: 1.1 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): 1.56
gnomAD pLI: 0
gnomAD missense Z: -0.24
DepMap mean gene effect: -0.06
DepMap dependency class: selective

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

Molecular functions

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of CIB4 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

ITGA2B

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CIB4 as an antibody target. Whether an autoantibody or antibody against CIB4 could matter depends on whether native CIB4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CIB4 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 CIB4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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