SPA17

Protein identityUniProt · HPA

UniProt accession

Q15506

Gene

SPA17

Ensembl

ENSG00000064199

Chromosome

11

Canonical length

151 aa

Protein class

Predicted intracellular proteins

Subcellular location

Golgi apparatus,Vesicles,Principal piece

Quaternary structure

Homodimer

OverviewNCBI Gene

This gene encodes a protein present at the cell surface. The N-terminus has sequence similarity to human cAMP-dependent protein kinase A (PKA) type II alpha regulatory subunit (RIIa) while the C-terminus has an IQ calmodulin-binding motif. The central portion of the protein has carbohydrate binding motifs and likely functions in cell-cell adhesion. The protein was initially characterized by its involvement in the binding of sperm to the zona pellucida of the oocyte. Recent studies indicate that it is also involved in additional cell-cell adhesion functions such as immune cell migration and metastasis. A retrotransposed pseudogene is present on chromosome 10q22.[provided by RefSeq, Jan 2009]

Canonical amino-acid sequenceUniProt

151 residues, UniProt reviewed canonical sequence.

>Q15506|SPA17
     1  MSIPFSNTHY RIPQGFGNLL EGLTREILRE QPDNIPAFAA AYFESLLEKR EKTNFDPAEW
    61  GSKVEDRFYN NHAFEEQEPP EKSDPKQEES QISGKEEETS VTILDSSEED KEKEEVAAVK
   121  IQAAFRGHIA REEAKKMKTN SLQNEEKEEN K

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SPA17 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

Cell surface

Secreted

No

Transmembrane segments

0

Mean surface accessibility (rSASA)

0.51

Highest tissue expression

37 nTPM

Expression across tissuesHPA

ReferencesPubMed · IEDB

Publications for SPA17 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.

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)

1.4

gnomAD pLI

0.01

gnomAD missense Z

-0.16

DepMap mean gene effect

0.1

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

• binding of sperm to zona pellucida
• epithelial cilium movement involved in extracellular fluid movement
• single fertilization
• spermatogenesis

Molecular functions

• calmodulin binding

Cellular components

• cilium
• cytoplasm
• external side of plasma membrane
• extracellular region
• motile cilium
• neuron projection
• sperm fibrous sheath
• sperm principal piece

Protein domainsUniProt · Pfam · InterPro

• IQ motif, EF-hand binding site
• cAMP-dependent protein kinase regulatory subunit, dimerization-anchoring domain
• CABYR/SP17, dimerization domain
• IQ calmodulin-binding motif
• Regulatory subunit of type II PKA R-subunit
• Sperm surface protein Sp17

KeywordsUniProt

• Membrane

InteractionsUniProt · HPA

Protein binding partners of SPA17 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• AKAP7
• MYL6B
• ROPN1L