Seroatlas · Human Serome Atlas

KRT33B

Keratin, type I cuticular Ha3-II

Also known as: Ha-3II, KRTHA3B, KT33B_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q14525
Gene
KRT33B
Ensembl
ENSG00000131738
Chromosome
17
Canonical length
404 aa
Protein class
Plasma proteins, Predicted intracellular proteins
Subcellular location
Cytosol,Equatorial segment,Mid piece,Principal piece,End piece

OverviewNCBI Gene

This gene encodes a member of the keratin gene family. This gene is one of multiple type I hair keratin genes that are clustered in a region of chromosome 17q12-q21 and have the same direction of transcription. As a type I hair keratin, the encoded protein is an acidic protein which heterodimerizes with type II keratins to form hair and nails. There are two isoforms of this protein, encoded by two separate genes, keratin 33A and keratin 33B. [provided by RefSeq, May 2012]

Canonical amino-acid sequenceUniProt

404 residues, UniProt reviewed canonical sequence.

>Q14525|KRT33B
     1  MPYNFCLPSL SCRTSCSSRP CVPPSCHGYT LPGACNIPAN VSNCNWFCEG SFNGSEKETM
    61  QFLNDRLASY LEKVRQLERD NAELENLIRE RSQQQEPLLC PSYQSYFKTI EELQQKILCS
   121  KSENARLVVQ IDNAKLAADD FRTKYQTEQS LRQLVESDIN SLRRILDELT LCRSDLEAQM
   181  ESLKEELLSL KQNHEQEVNT LRCQLGDRLN VEVDAAPAVD LNQVLNETRN QYEALVETNR
   241  REVEQWFATQ TEELNKQVVS SSEQLQSYQA EIIELRRTVN ALEIELQAQH NLRYSLENTL
   301  TESEARYSSQ LSQVQSLITN VESQLAEIRS DLERQNQEYQ VLLDVRARLE CEINTYRSLL
   361  ESEDCKLPSN PCATTNACEK PIGSCVTNPC GPRSRCGPCN TFGY

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KRT33B 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
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.53
Highest tissue expression
74 nTPM

Expression across tissuesHPA

Tissue

  • skin: 74 nTPM
  • thymus: 1.3 nTPM
  • salivary gland: 1.1 nTPM
  • adipose tissue: 0.6 nTPM
  • cerebral cortex: 0.4 nTPM
  • cervix: 0.2 nTPM

Single-cell type

  • epididymal basal cells: 0.2 nCPM
  • brain excitatory neurons: 0.1 nCPM
  • extravillous trophoblasts: 0.1 nCPM
  • migrating cytotrophoblasts: 0.1 nCPM
  • suprabasal keratinocytes: 0.1 nCPM
  • syncytiotrophoblasts: 0.1 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

  • basal ganglia: 0.1 nTPM
  • amygdala: 0 nTPM
  • cerebellum: 0 nTPM
  • cerebral cortex: 0 nTPM
  • choroid plexus: 0 nTPM
  • hippocampal formation: 0 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)
1.66
gnomAD pLI
0
gnomAD missense Z
-0.47
DepMap mean gene effect
-0.05
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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 KRT33B 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 KRT33B as an antibody target. Whether an autoantibody or antibody against KRT33B could matter depends on whether native KRT33B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KRT33B is annotated as secreted, so native KRT33B circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label KRT33B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KRT33B. 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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