Seroatlas · Human Serome Atlas

SMC1B

Structural maintenance of chromosomes protein 1B

Also known as: bK268H5, SMC1B_HUMAN, SMC1L2

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

Protein identityUniProt · HPA

UniProt accession
Q8NDV3
Gene
SMC1B
Ensembl
ENSG00000077935
Chromosome
22
Canonical length
1235 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Cytosol

OverviewNCBI Gene

SMC1L2 belongs to a family of proteins required for chromatid cohesion and DNA recombination during meiosis and mitosis (3:Revenkova et al., 2001 [PubMed 11564881]).[supplied by OMIM, Mar 2008]

Canonical amino-acid sequenceUniProt

1235 residues, UniProt reviewed canonical sequence.

>Q8NDV3|SMC1B
     1  MAHLELLLVE NFKSWRGRQV IGPFRRFTCI IGPNGSGKSN VMDALSFVMG EKIANLRVKN
    61  IQELIHGAHI GKPISSSASV KIIYVEESGE EKTFARIIRG GCSEFRFNDN LVSRSVYIAE
   121  LEKIGIIVKA QNCLVFQGTV ESISVKKPKE RTQFFEEIST SGELIGEYEE KKRKLQKAEE
   181  DAQFNFNKKK NIAAERRQAK LEKEEAERYQ SLLEELKMNK IQLQLFQLYH NEKKIHLLNT
   241  KLEHVNRDLS VKRESLSHHE NIVKARKKEH GMLTRQLQQT EKELKSVETL LNQKRPQYIK
   301  AKENTSHHLK KLDVAKKSIK DSEKQCSKQE DDIKALETEL ADLDAAWRSF EKQIEEEILH
   361  KKRDIELEAS QLDRYKELKE QVRKKVATMT QQLEKLQWEQ KTDEERLAFE KRRHGEVQGN
   421  LKQIKEQIED HKKRIEKLEE YTKTCMDCLK EKKQQEETLV DEIEKTKSRM SEVNEELNLI
   481  RSELQNAGID THEGKRQQKR AEVLEHLKRL YPDSVFGRLF DLCHPIHKKY QLAVTKVFGR
   541  FITAIVVASE KVAKDCIRFL KEERAEPETF LALDYLDIKP INERLRELKG CKMVIDVIKT
   601  QFPQLKKVIQ FVCGNGLVCE TMEEARHIAL SGPERQKTVA LDGTLFLKSG VISGGSSDLK
   661  YKARCWDEKE LKNLRDRRSQ KIQELKGLMK TLRKETDLKQ IQTLIQGTQT RLKYSQNELE
   721  MIKKKHLVAF YQEQSQLQSE LLNIESQCIM LSEGIKERQR RIKEFQEKID KVEDDIFQHF
   781  CEEIGVENIR EFENKHVKRQ QEIDQKRLEF EKQKTRLNVQ LEYSRSHLKK KLNKINTLKE
   841  TIQKGSEDID HLKKAEENCL QTVNELMAKQ QQLKDIRVTQ NSSAEKVQTQ IEEERKKFLA
   901  VDREVGKLQK EVVSIQTSLE QKRLEKHNLL LDCKVQDIEI ILLSGSLDDI IEVEMGTEAE
   961  STQATIDIYE KEEAFEIDYS SLKEDLKALQ SDQEIEAHLR LLLQQVASQE DILLKTAAPN
  1021  LRALENLKTV RDKFQESTDA FEASRKEARL CRQEFEQVKK RRYDLFTQCF EHVSISIDQI
  1081  YKKLCRNNSA QAFLSPENPE EPYLEGISYN CVAPGKRFMP MDNLSGGEKC VAALALLFAV
  1141  HSFRPAPFFV LDEVDAALDN TNIGKVSSYI KEQTQDQFQM IVISLKEEFY SRADALIGIY
  1201  PEYDDCMFSR VLTLDLSQYP DTEGQESSKR HGESR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SMC1B 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)
0.31
Highest tissue expression
29 nTPM

Expression across tissuesHPA

Tissue

  • testis: 29 nTPM
  • bone marrow: 0.2 nTPM
  • lymph node: 0.2 nTPM
  • tonsil: 0.2 nTPM
  • appendix: 0.1 nTPM
  • placenta: 0.1 nTPM

Single-cell type

  • early primary spermatocytes: 1,349 nCPM
  • differentiating spermatogonia: 511 nCPM
  • late primary spermatocytes: 105 nCPM
  • early spermatids: 101 nCPM
  • undifferentiated spermatogonia: 89 nCPM
  • oocytes: 37 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

  • cerebellum: 0.7 nTPM
  • choroid plexus: 0.6 nTPM
  • amygdala: 0.4 nTPM
  • basal ganglia: 0.4 nTPM
  • cerebral cortex: 0.4 nTPM
  • hippocampal formation: 0.4 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SMC1B.

Disease | GeneticClinVar

1 pathogenic / likely-pathogenic of 166 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on SMC1B was assayed in.

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)
0.36
gnomAD pLI
0.1
gnomAD missense Z
1.95
DepMap mean gene effect
-0.05
DepMap dependency class
selective

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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SMC1B as an antibody target. Whether an autoantibody or antibody against SMC1B could matter depends on whether native SMC1B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SMC1B 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 SMC1B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SMC1B. 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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