Seroatlas · Human Serome Atlas

FAM111B

Serine protease FAM111B

Also known as: CANP, F111B_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q6SJ93
Gene
FAM111B
Ensembl
ENSG00000189057
Chromosome
11
Canonical length
734 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Cytosol

OverviewNCBI Gene

This gene encodes a protein with a trypsin-like cysteine/serine peptidase domain in the C-terminus. Mutations in this gene are associated with an autosomal dominant form of hereditary fibrosing poikiloderma (HFP). Affected individuals display mottled pigmentation, telangiectasia, epidermal atrophy, tendon contractures, and progressive pulmonary fibrosis. Alternative splicing results in multiple transcript variants encoding distinct isoforms. A paralog of this gene which also has a trypsin‐like peptidase domain, FAM111A, is located only 16 kb from this gene on human chromosome 11q12.1. [provided by RefSeq, Apr 2014]

Canonical amino-acid sequenceUniProt

734 residues, UniProt reviewed canonical sequence.

>Q6SJ93|FAM111B
     1  MNSMKTEENK SFSAMEDDQR TRPEVSKDTV MKQTHADTPV DHCLSGIRKC SSTFKLKSEV
    61  NKHETALEMQ NPNLNNKECC FTFTLNGNSR KLDRSVFTAY GKPSESIYSA LSANDYFSER
   121  IKNQFNKNII VYEEKTIDGH INLGMPLKCL PSDSHFKITF GQRKSSKEDG HILRQCENPN
   181  MECILFHVVA IGRTRKKIVK INELHEKGSK LCIYALKGET IEGALCKDGR FRSDIGEFEW
   241  KLKEGHKKIY GKQSMVDEVS GKVLEMDISK KKALQQKDIH KKIKQNESAT DEINHQSLIQ
   301  SKKKVHKPKK DGETKDVEHS REQILPPQDL SHYIKDKTRQ TIPRIRNYYF CSLPRKYRQI
   361  NSQVRRRPHL GRRYAINLDV QKEAINLLKN YQTLNEAIMH QYPNFKEEAQ WVRKYFREEQ
   421  KRMNLSPAKQ FNIYKKDFGK MTANSVSVAT CEQLTYYSKS VGFMQWDNNG NTGNATCFVF
   481  NGGYIFTCRH VVHLMVGKNT HPSLWPDIIS KCAKVTFTYT EFCPTPDNWF SIEPWLKVSN
   541  ENLDYAILKL KENGNAFPPG LWRQISPQPS TGLIYLIGHP EGQIKKIDGC TVIPLNERLK
   601  KYPNDCQDGL VDLYDTTSNV YCMFTQRSFL SEVWNTHTLS YDTCFSDGSS GSPVFNASGK
   661  LVALHTFGLF YQRGFNVHAL IEFGYSMDSI LCDIKKTNES LYKSLNDEKL ETYDEEKGKQ
   721  ESSLQDHQIE PMEC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FAM111B 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)
0.4
Highest tissue expression
17 nTPM

Expression across tissuesHPA

Tissue

  • thymus: 17 nTPM
  • tonsil: 12 nTPM
  • lymph node: 11 nTPM
  • appendix: 5.5 nTPM
  • rectum: 5.4 nTPM
  • colon: 5.2 nTPM

Single-cell type

  • respiratory deuterosomal cells: 433 nCPM
  • monocyte progenitors: 39 nCPM
  • esophageal basal cells: 29 nCPM
  • oocytes: 28 nCPM
  • enteric transient amplifying cells: 26 nCPM
  • enteric stem cells: 17 nCPM

Immune cell

  • memory B-cell: 3.3 nTPM
  • naive B-cell: 2.6 nTPM
  • neutrophil: 1.6 nTPM
  • T-reg: 0.7 nTPM
  • memory CD8 T-cell: 0.3 nTPM
  • basophil: 0.2 nTPM

Brain region

  • cerebellum: 18 nTPM
  • white matter: 17 nTPM
  • cerebral cortex: 16 nTPM
  • hypothalamus: 15 nTPM
  • basal ganglia: 14 nTPM
  • medulla oblongata: 14 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about FAM111B.

Disease | AllUniProt

Conditions FAM111B is implicated in, by any mechanism.

  • Poikiloderma, hereditary fibrosing, with tendon contractures, myopathy, and pulmonary fibrosis (POIKTMP) MIM:615704

Disease | GeneticClinVar

7 pathogenic / likely-pathogenic of 158 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Hereditary sclerosing poikiloderma with tendon and pulmonary involvement

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)
1.88
gnomAD pLI
0.1
gnomAD missense Z
-0.23
DepMap mean gene effect
0
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 FAM111B 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 FAM111B as an antibody target. Whether an autoantibody or antibody against FAM111B could matter depends on whether native FAM111B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FAM111B 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 FAM111B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FAM111B. 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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