OBJECTIVE: To characterize immunocytochemically the antigen recognized which appears at specific stages of germ cell development and acrosomal biogenesis by the novel monoclonal antibody (Mab 3C2). METHODS: The novel monoclonal antibody (Mab 3C2) raised against testicular Sertoli and germ cells. RESULTS: The immunoreactivity of this Mab in testicular sections from immature 20-day-old rats was c...

A novel profilin, named profilin IV, was cloned and characterized as a testicular isoform, distinct from the previously described testis-specific profilin III. Profilin IV showed only 30% amino acid identity with the other mammalian profilins; nevertheless, database searches produced significant alignments with the conserved profilin domain. Northern blot analysis and in situ transcript hybridi...

Zona pellucida (ZP)-induced acrosome reaction in sperm is a required step for mammalian fertilization. However, the precise mechanism of the acrosome reaction remains unclear. We previously reported that PLCdelta4 is involved in the ZP-induced acrosome reaction in mouse sperm. Here we have monitored Ca2+ responses in single sperm, and we report that the [Ca2+]i increase in response to ZP, which...

Gamete recognition in the mouse is mediated by galactosyltransferase (GalTase) on the sperm surface, which binds to its appropriate glycoside substrate in the egg zona pellucida (Lopez, L. C., E. M. Bayna, D. Litoff, N. L. Shaper, J. H. Shaper, and B. D. Shur, 1985, J. Cell Biol., 101:1501-1510). GalTase has been localized by indirect immunofluorescence to the dorsal surface of the anterior spe...

Background The role of calcium in physiological phenomenona such as sperm acrosome reaction and hyper-activation has been well known. Calcium ionophore A23187 is routinely used for induction of acrosome reaction in mammalians sperm. Therefore, we decided to evaluate the effect of calcium ionophore A23187 on the sperm hyper-active motility patterns. MaterialsAndMethods Ten semen samples from ind...

The divalent metal cation ionophore A23187 induces an acrosome reaction in guinea-pig sperm which is dependent on external calcium. Examination of this acrosome reaction by electron microscopy shows that it is morphologically normal. The known properties of A23187 and the morphological similarity between the acrosome reaction and the secretory discharges of other secretory cells suggests that t...

This study evaluates the use of two fluorescein-labelled (FITC) plant lectins, Pisum sativum (edible pea) agglutinin (PSA) and Arachis hypogaea (peanut) agglutinin (PNA), in order to determine the most accurate and reliable method to experimentally detect and assess the acrosome reaction in mouse spermatozoa. PNA-FITC labelling was restricted to the acrosome and was not influenced by the fixati...

Evidence has accumulated suggesting multiple roles of acrosin in fertilization, including its participation in early steps of gamete recognition and binding. However, the implication of acrosin in many of these processes is not compatible with its presumptive sequestration within the sperm acrosome until a late phase of the acrosome reaction. In an earlier study (J. Tesarik, J. Drahorad, J. Pek...

We have identified a possible role for the KIFC1 motor protein in formation of the acrosome, an organelle unique to spermatogenesis. KIFC1, a C-terminal kinesin motor, first appears on membrane-bounded organelles (MBOs) in the medulla of early spermatids followed by localization to the acrosomal vesicle. KIFC1 continues to be present on the acrosome of elongating spermatids as it flattens on th...

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