Presence, processing, and localization of mouse ADAM15 during sperm maturation and the role of its disintegrin domain during sperm-egg binding.
Successful fertilization requires gametes to complete several stages, beginning with maturation and transport along the male and female reproductive tracts and ending with the interaction between the sperm and the egg. This last step involves sperm-egg adhesion and membrane fusion. ADAMs (disintegrin and metalloprotease domain proteins) are a family of membrane-anchored glycoproteins that are thought to play diverse roles in cell-cell adhesion through their interaction with integrins. This study analyzes the presence, location, processing, and possible role of ADAM15 in mouse sperm. The presence of ADAM15 in mouse spermatozoa was detected by Western blotting, which revealed that ADAM15 is post-translationally processed, during epididymal sperm maturation and the acrosome reaction. The 35 kDa antigen present in the acrosome-reacted sperm is the last proteolytic product of the 110/75 kDa ADAM15 found in non-capacitated sperm. This 35 kDa protein contains the disintegrin domain. By indirect immunofluorescence, ADAM15 was identified in the acrosomal region and along the flagellum of mouse spermatozoa. In acrosome-reacted sperm, ADAM15 was lost from the acrosomal region, but remained diffusely distributed throughout the head and flagellum. Furthermore, the ADAM15 disintegrin domain (RPPTDDCDLPEF) partially inhibited fusion and almost completely inhibited sperm-oolemma adhesion. In conclusion, our data indicate that ADAM15 is present in the testis and in spermatozoa from the caput, corpus, and cauda epididymis, as well as in non-capacitated and acrosome-reacted gametes. Results also indicate that ADAM15 is processed during epididymal maturation and acrosome reaction and that it may play a role during sperm-egg binding.
Pastén-Hidalgo
Karina
K
Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional No. 2508 (CINVESTAV-IPN), PC 07360, México, DF, México.
Hernández-Rivas
Rosaura
R
Roa-Espitia
Ana Lilia
AL
Sánchez-Gutiérrez
Manuel
M
Martínez-Pérez
Francisco
F
Monrroy
Alma Olivia
AO
Hernández-González
Enrique O
EO
Mújica
Adela
A
D051722:ADAM Proteins / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D000177:Acrosome / Q000737:chemistry; D020101:Acrosome Reaction; D000818:Animals; D015153:Blotting, Western / Q000379:methods; D019483:Disintegrins / Q000378:metabolism; D005260:Female; D005307:Fertilization in Vitro; D019084:Fluorescent Antibody Technique, Indirect; D008297:Male; D008565:Membrane Proteins / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D010446:Peptide Fragments / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D013079:Sperm Maturation / Q000502:physiology*; D013082:Sperm Tail / Q000737:chemistry; D013084:Sperm-Ovum Interactions / Q000502:physiology*; D013094:Spermatozoa / Q000737:chemistry* / Q000378:metabolism
D019483:Disintegrins; D008565:Membrane Proteins; D010446:Peptide Fragments; D051722:ADAM Proteins; C490902:Adam15 protein, mouse