Seroatlas · Human Serome Atlas

IQCB1

IQ calmodulin-binding motif-containing protein 1

Also known as: IQCB1_HUMAN, KIAA0036, NPHP5, SLSN5

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

Protein identityUniProt · HPA

UniProt accession
Q15051
Gene
IQCB1
Ensembl
ENSG00000173226
Chromosome
3
Canonical length
598 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Microtubules,Cytokinetic bridge,Mitotic spindle,Primary cilium,Basal body

OverviewNCBI Gene

This gene encodes a nephrocystin protein that interacts with calmodulin and the retinitis pigmentosa GTPase regulator protein. The encoded protein has a central coiled-coil region and two calmodulin-binding IQ domains. It is localized to the primary cilia of renal epithelial cells and connecting cilia of photoreceptor cells. The protein is thought to play a role in ciliary function. Defects in this gene result in Senior-Loken syndrome type 5. Alternative splicing results in multiple transcript variants. A pseudogene of this gene is found on chromosome 6. [provided by RefSeq, Jan 2016]

Canonical amino-acid sequenceUniProt

598 residues, UniProt reviewed canonical sequence.

>Q15051|IQCB1
     1  MKPTGTDPRI LSIAAEVAKS PEQNVPVILL KLKEIINITP LGSSELKKIK QDIYCYDLIQ
    61  YCLLVLSQDY SRIQGGWTTI SQLTQILSHC CVGLEPGEDA EEFYNELLPS AAENFLVLGR
   121  QLQTCFINAA KAEEKDELLH FFQIVTDSLF WLLGGHVELI QNVLQSDHFL HLLQADNVQI
   181  GSAVMMMLQN ILQINSGDLL RIGRKALYSI LDEVIFKLFS TPSPVIRSTA TKLLLLMAES
   241  HQEILILLRQ STCYKGLRRL LSKQETGTEF SQELRQLVGL LSPMVYQEVE EQKLHQAACL
   301  IQAYWKGFQT RKRLKKLPSA VIALQRSFRS KRSKMLLEIN RQKEEEDLKL QLQLQRQRAM
   361  RLSRELQLSM LEIVHPGQVE KHYREMEEKS ALIIQKHWRG YRERKNFHQQ RQSLIEYKAA
   421  VTLQRAALKF LAKCRKKKKL FAPWRGLQEL TDARRVELKK RVDDYVRRHL GSPMSDVVSR
   481  ELHAQAQERL QHYFMGRALE ERAQQHREAL IAQISTNVEQ LMKAPSLKEA EGKEPELFLS
   541  RSRPVAAKAK QAHLTTLKHI QAPWWKKLGE ESGDEIDVPK DELSIELENL FIGGTKPP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against IQCB1 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)
0.39
Highest tissue expression
27 nTPM

Expression across tissuesHPA

Tissue

  • testis: 27 nTPM
  • tonsil: 24 nTPM
  • lymph node: 23 nTPM
  • breast: 22 nTPM
  • thymus: 21 nTPM
  • bone marrow: 19 nTPM

Single-cell type

  • early primary spermatocytes: 275 nCPM
  • plasma cells: 174 nCPM
  • b-cells: 137 nCPM
  • respiratory ciliated cells: 133 nCPM
  • neutrophil progenitors: 128 nCPM
  • pancreatic acinar cells: 118 nCPM

Immune cell

  • memory B-cell: 23 nTPM
  • naive B-cell: 22 nTPM
  • non-classical monocyte: 14 nTPM
  • intermediate monocyte: 12 nTPM
  • NK-cell: 12 nTPM
  • eosinophil: 12 nTPM

Brain region

  • cerebellum: 15 nTPM
  • choroid plexus: 15 nTPM
  • white matter: 14 nTPM
  • cerebral cortex: 13 nTPM
  • hypothalamus: 13 nTPM
  • medulla oblongata: 12 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about IQCB1.

Disease | AllUniProt

Conditions IQCB1 is implicated in, by any mechanism.

Disease | GeneticClinVar

94 pathogenic / likely-pathogenic of 630 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.9
gnomAD pLI
0
gnomAD missense Z
0.31
DepMap mean gene effect
-0.16
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 9% 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 IQCB1 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 IQCB1 as an antibody target. Whether an autoantibody or antibody against IQCB1 could matter depends on whether native IQCB1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

IQCB1 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 IQCB1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/IQCB1. 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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