Sperm receptors are located in the mammalian egg extracellular coat, or zona pellucida. Mouse and hamster sperm receptor glycoproteins, mZP3 (83 x 10(3) M(r)) and hZP3 (56 x 10(3) M(r)), respectively, have very similar polypeptides (44 x 10(3) M(r); 81% identical) that are glycosylated to different extents. Purified mZP3 and hZP3 can bind to mouse sperm, prevent them from binding to eggs and in...

Background: Cigarette smoking is associated with impairment of testicular function. Nicotine is a major component of cigarette smoke.In the present study we aimed to study the effect of administration of nicotine-melatonin on sperm parameters in adult mouse. Materials and Methods: Male NMRI mice were divided into 4 groups: 1) control(normal saline) group 2) nicotine treated group 3) melatonin t...

Background: Fertilization is a multistep process requiring spermatozoa with unique cellular structures and numerous germ cell-specific molecules that function in the various steps. In the highly coordinated process of male germ cell development, RNA splicing and polyadenylation help regulate gene expression to ensure formation of functional spermatozoa. Male germ cells express tauCstF-64 (Cstf2...

Background: Failed fertilization after intracytoplasmic sperm injection (ICSI) can be due to a reduced oocyte-activation capacity caused by reduced concentrations and abnormal localization of the oocyte-activation factor phospholipase C (PLC) zeta. Patients with this condition can be helped to conceive by artificial activation of oocytes after ICSI with calcium ionophore (assisted oocyte activa...

Interaction of rapidly evolving molecules imparts species specificity to sperm-egg recognition in marine invertebrates, but it is unclear whether comparable interactions occur during fertilization in any vertebrate species. In mammals, the sperm acrosomal protein zonadhesin is a rapidly evolving molecule with species-specific binding activity for the egg zona pellucida (ZP). Here we show using ...

We established rat embryonic stem (ES) cell lines from a double transgenic rat line which harbours CAG-GFP for ubiquitous expression of GFP in somatic cells and Acr3-EGFP for expression in sperm (green body and green sperm: GBGS rat). By injecting the GBGS rat ES cells into mouse blastocysts and transplanting them into pseudopregnant mice, rat spermatozoa were produced in mouse←rat ES chimeras....

The mouse Y chromosome carries 10 distinct genes or gene families that have open reading frames suggestive of retained functionality; it has been assumed that many of these function in spermatogenesis. However, we have recently shown that only two Y genes, the testis determinant Sry and the translation initiation factor Eif2s3y, are essential for spermatogenesis to proceed to the round spermati...

Both the sperm and oocyte are terminally differentiated cells, but within a very short post-fertilization period, their genomes are converted into a totipotent zygote. The process of this transformation has been studied in a number of mammals as well as in the pig, for which very inconsistent results have been published. To clarify these inconsistencies, we have used the interspecies intracytop...

background: in most mammals, the testis is always maintained at a lower temperature than that in the abdomen, and exposure of the testis to body temperature causes degeneration of germ cells. objective: in this research, the long effect of heat exposure on sperm parameters and microstructure of mouse testis were investigated. cryptorchid mouse were induced by exposure to abdominal heat. materia...