Seroatlas · Human Serome Atlas

SP4

Transcription factor Sp4

Also known as: HF1B, MGC130008, MGC130009, SP4_HUMAN, SPR-1

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

Protein identityUniProt · HPA

UniProt accession
Q02446
Gene
SP4
Ensembl
ENSG00000105866
Chromosome
7
Canonical length
784 aa
Protein class
Predicted intracellular proteins, Transcription factors
Subcellular location
Nucleoplasm,Cytosol

OverviewNCBI Gene

The protein encoded by this gene is a transcription factor that can bind to the GC promoter region of a variety of genes, including those of the photoreceptor signal transduction system. The encoded protein binds to the same sites in promoter CpG islands as does the transcription factor SP1, although its expression is much more restricted compared to that of SP1. This gene may be involved in bipolar disorder and schizophrenia. [provided by RefSeq, May 2016]

Canonical amino-acid sequenceUniProt

784 residues, UniProt reviewed canonical sequence.

>Q02446|SP4
     1  MSDQKKEEEE EAAAAAAMAT EGGKTSEPEN NNKKPKTSGS QDSQPSPLAL LAATCSKIGT
    61  PGENQATGQQ QIIIDPSQGL VQLQNQPQQL ELVTTQLAGN AWQLVASTPP ASKENNVSQP
   121  ASSSSSSSSS NNGSASPTKT KSGNSSTPGQ FQVIQVQNPS GSVQYQVIPQ LQTVEGQQIQ
   181  INPTSSSSLQ DLQGQIQLIS AGNNQAILTA ANRTASGNIL AQNLANQTVP VQIRPGVSIP
   241  LQLQTLPGTQ AQVVTTLPIN IGGVTLALPV INNVAAGGGT GQVGQPAATA DSGTSNGNQL
   301  VSTPTNTTTS ASTMPESPSS STTCTTTAST SLTSSDTLVS SADTGQYAST SASSSERTIE
   361  ESQTPAATES EAQSSSQLQP NGMQNAQDQS NSLQQVQIVG QPILQQIQIQ QPQQQIIQAI
   421  PPQSFQLQSG QTIQTIQQQP LQNVQLQAVN PTQVLIRAPT LTPSGQISWQ TVQVQNIQSL
   481  SNLQVQNAGL SQQLTITPVS SSGGTTLAQI APVAVAGAPI TLNTAQLASV PNLQTVSVAN
   541  LGAAGVQVQG VPVTITSVAG QQQGQDGVKV QQATIAPVTV AVGGIANATI GAVSPDQLTQ
   601  VHLQQGQQTS DQEVQPGKRL RRVACSCPNC REGEGRGSNE PGKKKQHICH IEGCGKVYGK
   661  TSHLRAHLRW HTGERPFICN WMFCGKRFTR SDELQRHRRT HTGEKRFECP ECSKRFMRSD
   721  HLSKHVKTHQ NKKGGGTALA IVTSGELDSS VTEVLGSPRI VTVAAISQDS NPATPNVSTN
   781  MEEF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SP4 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)
0.64
Highest tissue expression
13 nTPM

Expression across tissuesHPA

Tissue

  • thymus: 13 nTPM
  • retina: 8.3 nTPM
  • ovary: 7.8 nTPM
  • thyroid gland: 7.3 nTPM
  • tongue: 7.1 nTPM
  • parathyroid gland: 6.7 nTPM

Single-cell type

  • somatotrophs: 111 nCPM
  • lactotrophs: 111 nCPM
  • neutrophils: 108 nCPM
  • thyrotrophs: 105 nCPM
  • corticotrophs: 99 nCPM
  • pituicytes/fscs: 94 nCPM

Immune cell

  • eosinophil: 8.9 nTPM
  • T-reg: 8.4 nTPM
  • MAIT T-cell: 8.2 nTPM
  • naive CD4 T-cell: 8.2 nTPM
  • gdT-cell: 6.9 nTPM
  • naive CD8 T-cell: 6.9 nTPM

Brain region

  • cerebellum: 29 nTPM
  • white matter: 17 nTPM
  • basal ganglia: 14 nTPM
  • hypothalamus: 14 nTPM
  • medulla oblongata: 13 nTPM
  • cerebral cortex: 13 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SP4.

Disease | AutoantibodyPubMed

Conditions in which antibodies against SP4 are reported. Each links to that disease's full target list.

ReferencesPubMed · IEDB

Publications for SP4 from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

5 publications

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)
0.28
gnomAD pLI
0.99
gnomAD missense Z
0.4
DepMap mean gene effect
0.08
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SP4 as an antibody target. Whether an autoantibody or antibody against SP4 could matter depends on whether native SP4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SP4 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 SP4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SP4. 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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