Protein: Izumo sperm-egg fusion protein 1 (Oocyte binding/fusion factor) (OBF) (Sperm-specific protein izumo) (Q8IYV9)
Organism: Homo sapiens (Human)
Function: Essential sperm cell-surface protein required for fertilization by acting as a ligand for IZUMO1R/JUNO receptor on egg. The IZUMO1:IZUMO1R/JUNO interaction is a necessary adhesion event between sperm and egg that is required for fertilization but is not sufficient for cell fusion. The ligand-receptor interaction probably does not act as a membrane 'fusogen'. Acts a ligand for the human-specific oolemma epitope FCRL3/MAIA during fertilization. FCRL3/MAIA replaces IZUMO1R/JUNO as IZUMO1 receptor after sperm-egg adhesion, which permits species-specific gamete fusion.
Subcellular location: Cell membrane {ECO:0000269|PubMed:15759005}; Single-pass type I membrane protein {ECO:0000255}. Cytoplasmic vesicle, secretory vesicle, acrosome membrane {ECO:0000269|PubMed:36070373}; Single-pass type I membrane protein {ECO:0000255}. Note=Localizes initially to the acrosome membrane of the sperm head (both outer and inner acrosomal membranes) (PubMed:36070373). During the acrosome reaction, translocates to the plasma membrane (PubMed:15759005, PubMed:36070373). {ECO:0000269|PubMed:15759005, ECO:0000269|PubMed:36070373}.
Sequence: MGPHFTLLCAALAGCLLPAEGCVICDPSVVLALKSLEKDYLPGHLDAKHHKAMMERVENAVKDFQELSLNEDAYMGVVDEATLQKGSWSLLKDLKRITDSDVKGDLFVKELFWMLHLQKETFATYVARFQKEAYCPNKCGVMLQTLIWCKNCKKEVHACRKSYDCGERNVEVPQMEDMILDCELNWHQASEGLTDYSFYRVWGNNTETLVSKGKEATLTKPMVGPEDAGSYRCELGSVNSSPATIINFHVTVLPKMIKEEKPSPNIVTPGEATTESSISLQPLQPEKMLASRLLGLLICGSLALITGLTFAIFRRRKVIDFIKSSLFGLGSGAAEQTQVPKEKATDSRQQ
InterPro domains: - IPR029389: Izumo sperm-egg fusion protein (family) [21-165]
- IPR036179: Immunoglobulin-like domain superfamily (homologous_superfamily) [169-253]
- IPR013783: Immunoglobulin-like fold (homologous_superfamily) [166-256]
- IPR032699: Izumo protein, immunoglobulin domain (domain) [168-255]
- IPR032700: Izumo sperm-egg fusion protein 1 (family) [1-347]
Interaction partners: - Sperm-egg fusion protein Juno
- CD9 antigen
- Sperm-egg fusion protein TMEM95
- Izumo sperm-egg fusion protein 4
- Sperm acrosome membrane-associated protein 6
- Sperm acrosome membrane-associated protein 1
- Acrosin
- Zona pellucida sperm-binding protein 3
- Izumo sperm-egg fusion protein 2
- Izumo sperm-egg fusion protein 3
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0005515 (protein binding), GO:0005102 (signaling receptor binding)
Biological Process (BP): GO:0008150 (biological process), GO:0048518 (positive regulation of biological process), GO:0050789 (regulation of biological process), GO:0023052 (signaling), GO:0032501 (multicellular organismal process), GO:0065007 (biological regulation), GO:0050896 (response to stimulus), GO:0032502 (developmental process), GO:0009987 (cellular process), GO:0048519 (negative regulation of biological process), GO:0048869 (cellular developmental process), GO:0048856 (anatomical structure development), GO:0023056 (positive regulation of signaling), GO:0007275 (multicellular organism development), GO:0023057 (negative regulation of signaling), GO:0042221 (response to chemical), GO:0048584 (positive regulation of response to stimulus), GO:0002682 (regulation of immune system process), GO:0071840 (cellular component organization or biogenesis), GO:0050793 (regulation of developmental process), GO:0002683 (negative regulation of immune system process), GO:0050794 (regulation of cellular process), GO:0048583 (regulation of response to stimulus), GO:0051716 (cellular response to stimulus), GO:0023051 (regulation of signaling), GO:0048523 (negative regulation of cellular process), GO:0048585 (negative regulation of response to stimulus), GO:0007154 (cell communication), GO:0007165 (signal transduction), GO:0048522 (positive regulation of cellular process), GO:0009967 (positive regulation of signal transduction), GO:0060759 (regulation of response to cytokine stimulus), GO:0009968 (negative regulation of signal transduction), GO:0010648 (negative regulation of cell communication), GO:0044085 (cellular component biogenesis), GO:0048468 (cell development), GO:0030154 (cell differentiation), GO:0080134 (regulation of response to stress), GO:0048731 (system development), GO:0009966 (regulation of signal transduction), GO:0032101 (regulation of response to external stimulus), GO:0060760 (positive regulation of response to cytokine stimulus), GO:0060761 (negative regulation of response to cytokine stimulus), GO:0010033 (response to organic substance), GO:0031348 (negative regulation of defense response), GO:0002831 (regulation of response to biotic stimulus), GO:0050776 (regulation of immune response), GO:0010646 (regulation of cell communication), GO:0070887 (cellular response to chemical stimulus), GO:0045595 (regulation of cell differentiation), GO:0016043 (cellular component organization), GO:0010647 (positive regulation of cell communication), GO:0007166 (cell surface receptor signaling pathway), GO:0002832 (negative regulation of response to biotic stimulus), GO:0032102 (negative regulation of response to external stimulus), GO:0031347 (regulation of defense response), GO:0034097 (response to cytokine), GO:0050728 (negative regulation of inflammatory response), GO:0045089 (positive regulation of innate immune response), GO:0045088 (regulation of innate immune response), GO:0001959 (regulation of cytokine-mediated signaling pathway), GO:0071310 (cellular response to organic substance), GO:0045824 (negative regulation of innate immune response), GO:1904892 (regulation of receptor signaling pathway via STAT), GO:0022607 (cellular component assembly), GO:0045637 (regulation of myeloid cell differentiation), GO:0045639 (positive regulation of myeloid cell differentiation), GO:0050727 (regulation of inflammatory response), GO:0050729 (positive regulation of inflammatory response), GO:1902105 (regulation of leukocyte differentiation), GO:0043933 (protein-containing complex organization), GO:0019221 (cytokine-mediated signaling pathway), GO:0046427 (positive regulation of receptor signaling pathway via JAK-STAT), GO:0065003 (protein-containing complex assembly), GO:0046425 (regulation of receptor signaling pathway via JAK-STAT), GO:0035162 (embryonic hemopoiesis), GO:0071345 (cellular response to cytokine stimulus), GO:2001237 (negative regulation of extrinsic apoptotic signaling pathway), GO:1902036 (regulation of hematopoietic stem cell differentiation), GO:0002252 (immune effector process), GO:0034612 (response to tumor necrosis factor), GO:0060338 (regulation of type I interferon-mediated signaling pathway), GO:0051259 (protein complex oligomerization), GO:0071356 (cellular response to tumor necrosis factor), GO:0051260 (protein homooligomerization)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0016020 (membrane), GO:0071944 (cell periphery), GO:0005737 (cytoplasm), GO:0012505 (endomembrane system), GO:0031090 (organelle membrane), GO:0030141 (secretory granule), GO:0031410 (cytoplasmic vesicle), GO:0043229 (intracellular organelle), GO:0043227 (membrane-bounded organelle), GO:0005886 (plasma membrane), GO:0101002 (ficolin-1-rich granule), GO:0099503 (secretory vesicle), GO:0043231 (intracellular membrane-bounded organelle), GO:0098588 (bounding membrane of organelle), GO:0012506 (vesicle membrane), GO:0042581 (specific granule), GO:0030667 (secretory granule membrane), GO:0070820 (tertiary granule), GO:0031982 (vesicle), GO:0030659 (cytoplasmic vesicle membrane), GO:0097708 (intracellular vesicle), GO:0070821 (tertiary granule membrane), GO:0101003 (ficolin-1-rich granule membrane), GO:0035579 (specific granule membrane)