Seroatlas · Human Serome Atlas

SPMAP2

Sperm microtubule associated protein 2

Also known as: CT56, SPMA2_HUMAN, THEG, THEG1

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

Protein identityUniProt · HPA

UniProt accession
Q9P2T0
Gene
SPMAP2
Ensembl
ENSG00000105549
Chromosome
19
Canonical length
379 aa
Protein class
Predicted intracellular proteins
Subcellular location
Cytosol,Equatorial segment,Principal piece,Annulus

OverviewNCBI Gene

This gene is specifically expressed in the nucleus of haploid male germ cells. The orthologous gene in mice encodes a protein that may play a role in protein assembly through interactions with T-complex protein 1 subunit epsilon. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Nov 2011]

Canonical amino-acid sequenceUniProt

379 residues, UniProt reviewed canonical sequence.

>Q9P2T0|SPMAP2
     1  MGDSRRRSLG NQPSSEAAGR SEREQDGDPR GLQSSVYESR RVTDPERQDL DNAELGPEDP
    61  EEELPPEEVA GEEFPETLDP KEALSELERV LDKDLEEDIP EISRLSISQK LPSTTMTKAR
   121  KRRRRRRLME LAEPKINWQV LKDRKGRCGK GYAWISPCKM SLHFCLCWPS VYWTERFLED
   181  TTLTITVPAV SRRVEELSRP KRFYLEYYNN NRTTPVWPIP RSSLEYRASS RLKELAAPKI
   241  RDNFWSMPMS EVSQVSRAAQ MAVPSSRILQ LSKPKAPATL LEEWDPVPKP KPHVSDHNRL
   301  LHLARPKAQS DKCVPDRDPR WEVLDVTKKV VASPRIISLA KPKVRKGLNE GYDRRPLASM
   361  SLPPPKASPE KCDQPRPGL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SPMAP2 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)
0.67
Highest tissue expression
40 nTPM

Expression across tissuesHPA

Tissue

  • testis: 40 nTPM
  • skin: 2.6 nTPM
  • epididymis: 1.3 nTPM
  • cerebral cortex: 0.8 nTPM
  • endometrium: 0.4 nTPM
  • duodenum: 0.3 nTPM

Single-cell type

  • late spermatids: 995 nCPM
  • early spermatids: 152 nCPM
  • late primary spermatocytes: 108 nCPM
  • epididymal principal cells: 10 nCPM
  • epididymal basal cells: 5.1 nCPM
  • breast secretory cells: 2.1 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

  • cerebral cortex: 2.3 nTPM
  • white matter: 1.9 nTPM
  • spinal cord: 1.1 nTPM
  • basal ganglia: 1 nTPM
  • amygdala: 0.5 nTPM
  • hypothalamus: 0.4 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)
1.35
gnomAD pLI
0
DepMap mean gene effect
0.05
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of SPMAP2 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 SPMAP2 as an antibody target. Whether an autoantibody or antibody against SPMAP2 could matter depends on whether native SPMAP2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SPMAP2 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 SPMAP2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SPMAP2. 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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