Heritable mutations in the germ line lead to genetically heterogeneous, or mosaic, gonads. Many of the genes used in germ-line development also play roles in somatic development [Saffman, E. E. & Lasko, P. (1999) Cell. Mol. Life Sci. 55, 1141-1163]. Mutations in these genes may have cellular phenotypes throughout germ-line development leading to their differential elimination or survival, as ha...

The Caenorhabditis elegans germ line is an outstanding model system in which to study the control of cell division and differentiation. Although many of the molecules that regulate germ cell proliferation and fate decisions have been identified, how these signals interact with cellular dynamics and physical forces within the gonad remains poorly understood. We therefore developed a dynamic, 3D ...

The C. elegans germ line is generated by extensive proliferation of the two germ-line progenitor cells present in newly hatched larvae. We describe genetic and phenotypic characterization of glp-4, a locus whose product is required for normal proliferation of the germ line. glp-4(bn2ts) mutant worms raised at the restrictive temperature contain approximately 12 germ nuclei, in contrast to the 7...

In Drosophila melanogaster, primordial germ cells are specified at the posterior pole of the very early embryo. This process is regulated by the posterior localized germ plasm that contains a large number of RNAs of maternal origin. Transcription in the primordial germ cells is actively down-regulated until germ cell fate is established. Bulk expression of the zygotic genes commences concomitan...

Germinal epithelium of seminiferous tubules in adult, infertile hypodactylous males displays significant reduction in the number of germ-line cells. Detection of apoptosis in the germ-line cells during postnatal differentiation was performed to elucidate the mechanism of the decreased number of germ cells in the testes of adult rats. Evaluation of DNA fragmentation and expression of activated c...

The germ line is unique in that highly specialised cells must be formed while retaining genomic totipotency. In mice, germ cells are derived from the pluripotent epiblast cells under the influence of inductive signals. This specification event involves reactivation or maintenance of core regulators of pluripotency, activation of germ line specific genetic programs, silencing of somatic cell pro...