Identification of a binding site in the disintegrin domain of fertilin required for sperm-egg fusion.
Fertilization and certain later stages in mammalian embryonic development require fusion between membranes of individual cells. The mechanism of eukaryotic cell-cell fusion is unknown, and no surface molecules required for this process have been unequivocally identified. The role of the sperm surface protein fertilin in sperm-egg fusion was tested by using peptide analogues of a potential integrin binding site in the fertilin beta subunit. Peptide analogues that include a TDE sequence from the disintegrin region of fertilin beta are able to bind to the egg plasma membrane and strongly inhibit sperm-egg fusion. These results show that the disintegrin domain of fertilin beta binds to the egg plasma membrane and that this binding is required for membrane fusion.
Myles
D G
DG
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
Kimmel
L H
LH
Blobel
C P
CP
White
J M
JM
Primakoff
P
P
D051722:ADAM Proteins; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D019483:Disintegrins; D005260:Female; D000072196:Fertilins; D006168:Guinea Pigs; D008297:Male; D008561:Membrane Fusion / Q000187:drug effects; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000378:metabolism*; D008666:Metalloendopeptidases; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000494:pharmacology*; D009865:Oocytes / Q000502:physiology*; D010455:Peptides / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D013084:Sperm-Ovum Interactions / Q000187:drug effects; D013094:Spermatozoa / Q000502:physiology*; D015044:Zona Pellucida / Q000187:drug effects
D019483:Disintegrins; D008562:Membrane Glycoproteins; D009842:Oligopeptides; D010455:Peptides; D051722:ADAM Proteins; D000072196:Fertilins; D008666:Metalloendopeptidases