Interspecific hybrids can be studied using methodologies in which the male gamete with high reproduction potential, viability, and fertility is prioritized. Passiflora species, lush, showy, exotic colors, have great potential for ornamental plant market. In addition, artificial were developed without many difficulties because of weak reproductive barriers. Thus, meiotic post-meiotic behaviors a...

Rad51 protein of Saccharomyces cerevisiae is a structural homolog of the Escherichia coli recombination enzyme RecA. In yeast, the Rad51 protein is required for mitotic and meiotic recombination and for repair of double-strand breaks in DNA. We have used antibodies raised against the homologous human protein, HsRad51, expressed in E. coli, to visualize the spatial distribution of the protein in...

At fertilization, the spermatozoon is generally held to generate two important second messengers, inositol trisphosphate and diacylglycerol. A similar situation arises when these signalling molecules are generated after a hormone binds to its plasma membrane receptor. This signalling mechanism releases intracellular Ca2+ which causes cortical granule release and initiates meiotic resumption. Th...

Oocyte meiotic spindles are associated with spindle-enriched mRNAs, phosphorylated ribosome protein S6, and phosphorylated variants of the key translational regulator, eukaryotic translation initiation factor 4E-binding protein 1 (eIF4E-BP1), consistent with translational control of localized mRNAs by eIF4E-BP1 in facilitating spindle formation and stability. Using specific kinase inhibitors, w...

Drosophila melanogaster Polo kinase physically interacts with, and is repressed by, the Matrimony (Mtrm) protein during oogenesis. Females heterozygous for a deletion of the mtrm gene display defects in chromosome segregation at meiosis I. However, a complete absence of Mtrm results in both meiotic catastrophe and female sterility. We show that three phosphorylated residues in an N-terminal reg...

Fertilization increases both cytosolic Ca(2+) concentration and oxygen consumption in the egg but the relationship between these two phenomena remains largely obscure. We have measured mitochondrial oxygen consumption and the mitochondrial NADH concentration on single ascidian eggs and found that they increase in phase with each series of meiotic Ca(2+) waves emitted by two pacemakers (PM1 and ...

Background Infertility affects around 15% of couples, and male factors account for 50%. Cryptorchidism is one of the most common causes for azoospermia. Generation of functional spermatids from azoospermia patients is of unusual significance for treating male infertility. It has been recently reported by peers and us that human spermatogonial stem cells (SSCs) can be clearly identified and cult...

Objective(s): Dehydroepiandrosterone (DHEA) has been reported to improve pregnancy chances in women with diminished ovarian reserve (DOR) and to reduce miscarriage rates by 50–80%. This study, therefore, assesses effects of DHEA on number of retrieved oocytes and meiotic spindles.Materials and Methods: A randomized, prospective, controlled study was conducted on eight groups, four groups of you...

objective(s):leptin is a novel and interesting hormone for anyone trying to lose weight, but its effects on male gonad structure in longitudinal study is unknown. the present study was designed to explore morphometrical changes of mouse testicular tissue after long-term administration of leptin. materials and methods:thirty healthy mature male mice were randomly assigned to either control (n=15...