Background: Germ cell development processes are influenced by soluble factors and intercellular signaling events between them and the neighboring somatic cells. More insight into the molecular biology of the germ cell development from embryonic stem (ES) cells and investigation of appropriate factors, specifically those targeting differentiation process, is of great importance. In this study, w...

Segregation of the future germ line defines a crucial cell fate decision during animal development. In Xenopus, germ cells are specified by inheritance of vegetally localized maternal determinants, including a group of specific mRNAs. Here, we show that the vegetal localization elements (LE) of Xenopus Dead end (XDE) and of several other germ-line-specific, vegetally localized transcripts media...

In Drosophila, it has been postulated that the third intron of the P-element is spliced only in germ-line cells. To test whether this postulate is applicable to pole cells, the progenitor cells of germ line, we carried out a histochemical assay to detect the splicing activity in embryos. The splicing activity was detected in pole cells and primordial germ cells. The activity increased to reach ...

In Musca domestica, the common housefly, female development requires the continuous activity of the sex-determining gene F from early embryogenesis until metamorphosis. To activate F in embryogenesis, two conditions must be met: There must be no male-determining M factor in the zygotic genome, and the egg must be preconditioned by F activity in the maternal germ line. This maternal activity can...

In most animals, primordial germ cell (PGC) specification and development depend on maternally provided cytoplasmic determinants that constitute the so-called germ plasm. Little is known about the role of germ plasm in vertebrate germ cell development, and its molecular mode of action remains elusive. While PGC specification in mammals occurs via different mechanisms, several germ plasm compone...

In vitro derivation of germ cells from different stem cells sources has been challenging in the treatment of male infertility. MicroRNAs (miRNAs) have an essential role in gene expression at post-transcriptional level. The aim of this research was to find more about miRNA-17 and miRNA-146 expression during differentiation of spermatogonial stem cell like cells (SSC like cells) from mouse bone m...

P granules are non-membrane-bound organelles found in the germ-line cytoplasm throughout Caenorhabditis elegans development. Like their "germ granule" counterparts in other animals, P granules are thought to act as determinants of the identity and special properties of germ cells, properties that include the unique ability to give rise to all tissues of future generations of an organism. Theref...

Background: Nicotine as a toxic agent in cigarette has detrimental effects on reproduction. The aim of this study was to evaluate effects of of nicotine on germ and somatic cells in adult mouse testis. Materials and Methods: Male mice were divided into four groups. Group A or controls, groups of B, C and D were treated with nicotine intraperitoneally in doses of 0.1, 0.2 and 0.4 mg/100 g body w...

In the mouse embryo, significant numbers of primordial germ cells (PGCs) fail to migrate correctly to the genital ridges early in organogenesis. These usually die in ectopic locations. In humans, 50% of pediatric germ line tumors arise outside the gonads, and these are thought to arise from PGCs that fail to die in ectopic locations. We show that the pro-apoptotic gene Bax, previously shown to ...

Gonocytes are a transient population of male germ-line stem cells that are derived from primordial germ cells in the embryo and give rise to spermatogonial stem cells, which establish and maintain spermatogenesis in the postnatal testis. In contrast to spermatogonial stem cells, gonocytes can be identified easily in neonatal rat testis cell suspensions based on their large size and distinct mor...