The domain within your query sequence starts at position 7 and ends at position 113; the E-value for the Motile_Sperm domain shown below is 9.7e-35.



PFAM accession number:PF00635
Interpro abstract (IPR000535):

Nematode sperm are unusual amoeboid cells in which motility is not based on actin, but instead on the major sperm protein (MSP). MSP is a dimeric molecule that polymerises to form non-polar filaments constructed from two helical subfilaments that wind round one another. The filaments then assemble into larger macromolecular assemblies called fibre complexes. MSP is a small (~14kDa) basic protein typically encoded by a multigene family of up to 28 members [ (PUBMED:8913307) (PUBMED:12051923) (PUBMED:9878374) (PUBMED:9641981) ]. An about 120-amino acid domain similar to MSP has been found in other proteins, including:

  • Animal Vesicle-Associated Membrane Protein-associated (VAMP-associated) protein family of 33kDa (VAP33). VAP33 is required for neurotransmitter release. It binds to the v-SNARE synaptobrevin/VAMP which is associated with vesicle fusion. VAP33 has a two-domain structure with its N terminus being highly homologous to MSP, whereas its C terminus is based on a putative alpha-helical coiled-coil combined with an extremly hydrophobic membrane-attachment region [ (PUBMED:9920726) ].
  • Nicotiana plumbaginifolia VAP27, a VAP33 homologue. It interacts with the resistance protein Cf9 [ (PUBMED:10733941) ].
  • Yeast inositol regulator SCS2, a VAP33 homologue. It is C-terminally anchored to the endoplasmic reticulum [ (PUBMED:9537365) ].

The MSP polypeptide chain has an immunoglobulin-like fold based on a seven- stranded beta sandwich measuring approximately 15 A x 20 A x 45 A and having opposing three-stranded and four-stranded beta sheets [ (PUBMED:8913307) ].

This entry represents the MSP domain.

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