The domain within your query sequence starts at position 3 and ends at position 61; the E-value for the Zona_pellucida domain shown below is 5.6e-8.

ADREALPFWSHYQRFTITTFMLLDSSSQNALRGQVYFFCSASACHPLGSDTCSTTCDSG

Zona_pellucida

Zona_pellucida
PFAM accession number:PF00100
Interpro abstract (IPR001507):

The zona pellucida (ZP) domain is a protein polymerisation module of ~260 amino acid module, which is found at the C terminus of many secreted eukaryotic glycoproteins that play fundamental roles in development, hearing, immunity, and cancer [ (PUBMED:1313375) (PUBMED:12021773) (PUBMED:12878193) (PUBMED:15079052) ]. Proteins containing a ZP domain include:

  • Sperm receptor proteins ZP2 and ZP3. Along with protein ZP1, proteins ZP2 and ZP3 are responsible for sperm-adhesion to the zona pellucida. ZP3 first binds to specific sperm proteins, thus mediating sperm contacts with the oocyte. ZP2 acts as a second sperm receptor reinforcing the interactions. ZP1 cross-links the polymers formed by ZP2 and ZP3.
  • Zona pellucida sperm-binding protein B (ZP-B) (also known as ZP-X in rabbit and ZP-3 alpha in pig).
  • Glycoprotein GP2, the major component of pancreatic secretory granule membranes.
  • TGF-beta receptor type III (also known as betaglycan). This protein is a proteoglycan that binds to TGF-beta and could be involved in capturing and retaining TGF-beta for presentation to the signalling receptors.
  • Uromodulin (also known as Tamm-Horsfall urinary glycoprotein). The function of this protein, which is the most abundant in human urine, is not yet clear.
  • Chicken beta-tectorin, a major glycoprotein of avian tectorial membrane.

Most ZP domain proteins are synthesized as precursors with carboxy-terminal transmembrane domains or glycosyl phosphatidylinositol (GPI) anchors [ (PUBMED:12021773) ].

The ZP domain contains eight strictly conserved cysteines, which form disulphide bridges. The disulphide bonds within the ZP domains are divided into two groups, suggesting that the ZP domain consists of two subdomains. In addition to the conserved cysteines, only a few aromatic or hydrophobic amino acids are absolutely invariant, probably as a result of structural rather than functional constraints [ (PUBMED:1313375) (PUBMED:12878193) (PUBMED:15079052) ].

This is a PFAM domain. For full annotation and more information, please see the PFAM entry Zona_pellucida