izumo 1

Expression system: E. coli
Length: 22-292, Partial
Activity: Not Tested

Izumo is a sperm membrane protein that plays a key role in the fusion in the mouse. It has an Immunoglobulin (Ig) domain and an N-terminal domain for which neither the functions nor homologous sequences are known. Up to now, there four members has an N-terminal domain with significant homology to the N-terminal domain of Izumo. We call this domain the Izumo domain. The four proteins are Izumo 1, 2, 3, and 4. Izumo domain possesses the ability to form dimers, whereas the transmembrane domain or the cytoplasmic domain, or both of Izumo 1 are required for the formation of multimers of a higher order. Izumo 1-3 are transmembrane proteins expressed specifically in the testis, and Izumo 4 is a soluble protein expressed in the testis and other tissues. Izumo 1, 3, and 4 formed protein complexes on sperm, Izumo 1 forming several larger complexes, and Izumo 3 and 4 forming a single larger complex. Izumo1 is essential for sperm-egg plasma membrane binding and fusion.

Izumo1 is the only essential sperm-egg fusion protein currently known on mammalian sperm, and its egg receptor (Juno; formerly Folr4) was recently discovered. Male knockout mice for Izumo1 and female knockout mice for Juno are both healthy but sterile. Here, both sperm-egg binding proteins are shown to be evolving under positive selection. Juno's presence in mammals alone, suggesting a recent mammalian-specific duplication and neofunctionalization of the ancestral folate receptor. FOLR4 Juno Protein, Human, Recombinant (His) is expressed in HEK293 mammalian cells with C-His tag. The predicted molecular weight is 25 kDa and the accession number is A6ND01-1.

Expression system: HEK293 Cells
Length: 20-222, Full Length of Mature Protein
Activity: Not Tested

Expression system: HEK293 Cells
Length: 1-214, Full Length
Activity: Not Tested