Summary: Izumo sperm-egg fusion, Ig domain-associated
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Izumo sperm-egg fusion, Ig domain-associated Provide feedback
This IZUMO family is a domain just upstream of the immunoglobulin domain on Izumo proteins in higher eukaryotes. The actual function of this region of the Izumo proteins is not known. The full-length protein is a molecule with a single immunoglobulin (Ig) domain. It is thought that Izumo proteins bind to putative Izumo receptors on the oocyte. Izumo is not detectable on the surface of fresh sperm but becomes exposed only after an exocytotic process, the acrosome reaction, has occurred. Studies have shown that knock-out mice (Izumo-/- males) were sterile despite normal mating behaviour and ejaculation, indicating the importance of the protein in fertilisation . There are cysteine residues thought to form a disulphide bridge. Izumo is a typical type I membrane glycoprotein with one immunoglobulin-like domain and a putative N-glycoside link motif (Asn 204) . There is a conserved GCL sequence motif. Izumo expression has been found to be testis-specific [1,2].
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This tab holds annotation information from the InterPro database.
InterPro entry IPR029389
Izumo is a protein with a single immunoglobulin (Ig) domain. Its expression has been found to be testis-specific [PUBMED:1, PUBMED:2]. Izumo is not detectable on the surface of fresh sperm, but becomes exposed after an exocytotic process, the acrosome reaction, has occurred. It is thought to bind to putative Izumo receptors on the oocyte. Studies have shown that knock-out mice (Izumo-/- males) were sterile despite normal mating behaviour and ejaculation, indicating the importance of the protein in fertilisation [PUBMED:16574441]. Izumo is a typical type I membrane glycoprotein with one immunoglobulin-like domain and a putative N-glycoside link motif (Asn 204) [PUBMED:15759005]. It contains cysteine residues thought to form a disulphide bridge, and a conserved GCL sequence motif.
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Curation and family details
|Author:||Coggill P, Hetherington K|
|Number in seed:||40|
|Number in full:||164|
|Average length of the domain:||132.40 aa|
|Average identity of full alignment:||28 %|
|Average coverage of the sequence by the domain:||50.75 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 80369284 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||2|
|Download:||download the raw HMM for this family|
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