in this study, we examined the chromosome number, detailed male meiosis, microsporogenesis, pollen fertility and distribution of cytotypes of diplotaxis harra (forssk.) boiss. this is the first cytogenetic report of the taxon. the two of the populations scored now from regions of the central showed aneuploid (x = 14) meiotic chromosome count and one of the populations studied from the existed a...

Meiotic drivers are genetic entities that increase their own probability of being transmitted to offspring, usually the detriment rest organism, thus ‘selfishly’ increasing fitness. In many meiotic drive systems, driver-carrying males less successful in sperm competition, which occurs when females mate with multiple one oestrus cycle (polyandry). How do respond this selection? An observational ...

An essential feature of meiosis is interhomolog recombination whereby a significant fraction of the programmed meiotic double-strand breaks (DSBs) is repaired using an intact homologous non-sister chromatid rather than a sister. Involvement of Mec1 and Tel1, the budding yeast homologs of the mammalian ATR and ATM kinases, in meiotic interhomlog bias has been implicated, but the mechanism remain...

Sexual reproduction is crucially dependent on meiosis, a conserved, specialized cell division programme that is essential for the production of haploid gametes. Here we demonstrate that fertility and the implementation of the meiotic programme require a previously uncharacterized meiosis-specific protein, MEIOC. Meioc invalidation in mice induces early and pleiotropic meiotic defects in males a...

ABSTRACT Heterochromatin-related epigenetic mechanisms, such as DNA methylation, facilitate pairing of homologous chromosomes during the meiotic prophase mammalian spermatogenesis. In pro-spermatogonia, de novo methylation plays a key role in completing and initiating division. However, maintenance regulation meiosis, especially adult, is not well understood. Here, we reveal that NP95 (also kno...

background: diabetes is the most common endocrine disease. it has adverse effects on male reproductive function. royal jelly (rj) has antioxidant and anti-diabetic effects and show protective effects against diabetes. objective: this study was conducted to evaluate the effect of rj on histopathological alterations of the testicular tissue in streptozotocin (stz)-induced diabetic rats. materials...

Development of yeast meiotic chromosome cores into full-length synaptonemal complexes requires the MEK1 gene product, a meiosis-specific protein kinase homolog. The Mek1 protein associates with meiotic chromosomes and colocalizes with the Red1 protein, which is a component of meiotic chromosome cores. Mek1 and Red1 interact physically in meiotic cells, as demonstrated by coimmunoprecipitation a...

The synaptonemal complex is an elaborate meiosis-specific supramolecular protein assembly that promotes chromosome synapsis and meiotic recombination. We inactivated the meiosis-specific gene Tex12 and found that TEX12 is essential for progression of meiosis in both male and female germ cells. Structural analysis of the synaptonemal complex in Tex12-/- meiocytes revealed a disrupted central ele...

The study of mammalian meiosis is complicated by the timing of meiotic events in females and by the intermingling of meiotic sub-stages with somatic cells in the gonad of both sexes. In addition, studies of mouse mutants for different meiotic regulators have revealed significant differences in the stringency of meiotic events in males versus females. This sexual dimorphism implies that the proc...