The germ lineage is considered to be immortal. In the quest to extend lifespan, a possible strategy is to drive germ-line traits in somatic cells, to try to confer some of the germ lineage's immortality on the somatic body. Notably, a study in Caenorhabditis elegans suggested that expression of germ-line genes in the somatic cells of long-lived daf-2 mutants confers some of daf-2's long lifespa...

Undifferentiated tammar wallaby ovaries were transplanted under the skin of male pouch young during the period of mitotic division of the XX germ cells. After 25 days, all the germ cells had disappeared and the ovaries contained seminiferous-like cords. Similarly, undifferentiated ovaries cultured for 4 days with recombinant human Müllerian-inhibiting substance (rhMIS) also contained well-diffe...

Formation of the male gamete occurs in sequential mitotic, meiotic, and postmeiotic phases. Many germ cell-specific transcripts are produced during this process. Their expression is developmentally regulated and stage specific. Some of these transcripts are product of genes that are male germ cell-specific homologs of genes expressed in somatic cells, while some are expressed from unique genes ...

Dye coupling experiments were performed to determine whether the gap junctions connecting Sertoli cells with other Sertoli cells and different germ cell stages in rats showed functional variations. Chop loading of adult rat seminiferous tubules was conducted using fluorescent dextran controls and a variety of low-molecular-weight tracers (lucifer yellow, biotin-X-cadaverine, biotin cadaverine, ...

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...

The colonial ascidian Botryllus schlosseri continuously regenerates entire bodies in an asexual budding process. The germ line of the newly developing bodies is derived from migrating germ cell precursors, but the signals governing this homing process are unknown. Here we show that germ cell precursors can be prospectively isolated based on expression of aldehyde dehydrogenase and integrin alph...

Ovarian tumors are formed either in the absence of Bam (bag-of-marbles) in germ-line cells or the overexpression of Dpp (decapentaplegic) in ovarian somatic cells. These tumor cells contain spectrosomes characteristic of ovarian germ-line stem cells and the immediate descendents called cystoblasts. We show that pole cells can successfully populate the gonad after transplantation to the dorsal m...

................................................................................................................................. 8 INTRODUCTION....................................................................................................................... 10 REVIEW OF LITERATURE..................................................................................................... 13 APOPT...

The influence of somatic environment on the onset and progression of meiosis in fetal germ cells was studied in chimeric gonads produced in vitro by dissociation-reaggregation experiments. Germ cells isolated from testes or ovaries of 11.5-13.5 days post coitum (dpc) CD-1 mouse embryos were loaded with the fluorescent supravital dye 5-6 carboxyfluorescein diacetate succinimyl ester (CFSE) and m...