Cyclic FEE peptide increases human gamete fusion and potentiates its RGD-induced inhibition.
BACKGROUND
Alpha6beta1 integrin has been proposed to act as a sperm receptor on the mouse oocyte by interacting with spermatozoon fertilin beta. We investigated, in humans, whether oocyte integrins could act similarly in gamete fusion, using a cyclic peptide containing the putative disintegrin-binding domain of human fertilin beta [cyclic FEE (cFEE)] and RGD peptide.


METHODS
Zona-free eggs were inseminated in the absence or presence of peptides. To maintain the membrane protein pattern, the zona pellucida was removed by microdissection. Immunofluorescence and confocal microscopy were used to detect integrin subunits on the oocyte.


RESULTS
Unexpectedly, cFEE alone increased human gamete fusion by 94% instead of inhibiting fertilization. Furthermore, cFEE together with RGD potentiated the RGD-induced inhibition of fertilization in a dose-dependent manner. The data suggested the hypothesis of integrin cross-talk, further supported by the co-localization of alpha6beta1 and alphavbeta3 integrins, the putative receptors of cFEE and RGD peptides, respectively.


CONCLUSIONS
RGD-sensitive and -insensitive integrins may be associated in a multimolecular complex working as a sperm receptor on the human oocyte membrane. Supplementation of human IVF culture medium with cFEE peptide might improve fertilization rates in ART.
Ziyyat
A
A
Laboratoire de Biologie de la Reproduction, UPRES 3410, UFR SMBH, Université Paris 13, 74, rue Marcel Cachin, 93017 Bobigny, Service d'Histologie-Embryologie-Cytogénétique, Hôpital Jean Verdier (Assistance Publique-Hôpitaux de Paris), Bondy, France.
Naud-Barriant
N
N
Barraud-Lange
V
V
Chevalier
F
F
Kulski
O
O
Lemkecher
T
T
Bomsel
M
M
Wolf
J P
JP
D051722:ADAM Proteins / Q000378:metabolism; D000818:Animals; D019921:Biotinylation; D002462:Cell Membrane / Q000378:metabolism; D000072196:Fertilins; D005306:Fertilization / Q000187:drug effects*; D005307:Fertilization in Vitro / Q000379:methods*; D005854:Germ Cells / Q000187:drug effects*; D006801:Humans; D039121:Integrin alpha6beta1 / Q000378:metabolism; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009842:Oligopeptides / Q000737:chemistry / Q000494:pharmacology*; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism; D010455:Peptides / Q000737:chemistry; D010456:Peptides, Cyclic / Q000494:pharmacology*; D017434:Protein Structure, Tertiary; D012661:Semen / Q000378:metabolism; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods; D013084:Sperm-Ovum Interactions / Q000187:drug effects; D013094:Spermatozoa / Q000378:metabolism
D039121:Integrin alpha6beta1; D039302:Integrin alphaVbeta3; D008562:Membrane Glycoproteins; D009842:Oligopeptides; D010455:Peptides; D010456:Peptides, Cyclic; C047981:arginyl-glycyl-aspartic acid; D051722:ADAM Proteins; C000606454:ADAM2 protein, human; C000606458:Adam2 protein, mouse; D000072196:Fertilins