germline and somatic stem cells are distinct types of stem cells that are dedicated to reproduction and somatic tissue regeneration, respectively. germline stem cells (gscs), which can self-renew and generate gametes, are unique stem cells in that they are solely dedicated to transmit genetic information from generation to generation. we developed a strategy for the establishment of germline st...

In Xenopus, factors with the ability to establish the germ line are localized in the vegetal pole cytoplasm, or germ plasm, of the early embryo [1-3]. The germ plasm of Xenopus, and of many other animal species including Drosophila, contains electron-dense germinal granules which may be essential for germ-line formation [4-5]. Several components of the germinal granules have so far been identif...

Translational control is a prevalent form of gene expression regulation in the Caenorhabditis elegans germ line. Linking the amount of protein synthesis to mRNA quantity and translational accessibility in the cell cytoplasm provides unique advantages over DNA-based controls for developing germ cells. This mode of gene expression is especially exploited in germ cell fate decisions and during oog...

Activation-induced cytidine deaminase (AID) initiates somatic hypermutation (SHM) and class switch recombination (CSR) in activated B lymphocytes and is potentially implicated in genomic instability of B-cell malignancies. For unknown reasons, B-cell neoplasms often lack SHM and CSR in spite of high AID expression. Here, we show that primary mediastinal B-cell lymphoma (PMBL), an immunoglobulin...

Although the zebrafish possesses many characteristics that make it a valuable model for genetic studies of vertebrate development, one deficiency of this model system is the absence of methods for cell-mediated gene transfer and targeted gene inactivation. In mice, embryonic stem cell cultures are routinely used for gene transfer and provide the advantage of in vitro selection for rare events s...

malignant germ-cell tumors (mgct) are rare tumors of childhood accounting for less than 3% of pediatric malignancies. endodermal sinus tumor (est) forms the most common histologic subtype of mgct. the vagina is an extremely rare site for gcts. an 8-month-old female was admitted with a short history of vaginal bleeding, and a mass protruding from the vagina. she was pale and a mass was palpable ...

malignant mixed germ cell tumors,though rare overall, are the most common type of malignant ovarian neoplasms in young and adolescent girls. these tumors are rapidly growing and can metastasize. we report a case of 13-yr-old girl who presented at shkm gmc, nalhar, mewat, haryana, india in december 2013 with huge abdominal lump of a malignant mixed germ cell tumor comprising both immature terato...

In 1902, the vertebrate embryologist James Beard wrote these words in his monograph on germ cells in the skate Raja batis [1]. Over 110 years later, germ line specification and development are indeed major areas of investigation in the fields of developmental biology and evolution. August Weismann’s description of the germ line as containing ‘‘unalterable accessory idioplasm’’ [2] may sound sus...

Recent studies on the ovary organization and oogenesis in Tubificinae have revealed that their ovaries are small polarized structures that are composed of germ cells in subsequent stages of oogenesis that are associated with somatic cells. In syncytial cysts, as a rule, each germ cell is connected to the central cytoplasmic mass, the cytophore, via only one stable intercellular bridge (ring can...