Lerit DA, Shebelut CW, Lawlor KJ, Rusan NM, Gavis ER, Schedl P, et al. Germ Cell-less Promotes Centrosome Segregation to Induce Germ Cell Formation.
Unlike fruit flies, which cannot form germ cells without oskar, removing the gene from crickets has no effect on germ cell formation.
Analysis of two newly identified oskar localization factors, Rumpelstiltskin and Lost, that are required specifically for this late phase of oskar localization shows that germ plasm amplification ensures robust abdomen and germ cell formation during embryogenesis.
He also investigated the basic cytological processes of cell division, germ cell formation, fertilization, and embryonic development, using microscopic description and carefully designed experiments to understand the relevance of centrosomes, chromosomes, and cytoplasm and their interplay.
This, as per our knowledge, is first such study in higher mammals, especially farm animals, and assumes significance for its potential use in transgenic animal production, elite animal conservation and propagation, augmentation of reproductive performance in poor breeding buffalo species, and as a model for understanding human germ cell formation.
Such mixing, which commonly happens to the chromosomal DNA during germ cell formation, is called recombination.
It was previously reported that specific Tudor domains are required for germ cell formation and Tud localization.
One such mutant includes tudA36 which has a point mutation in the first Tudor domain, suggesting that this Tudor domain may not be crucial for germ cell formation.
However, this mutation supports a significant level of germ cell formation, as does the tud4 mutation affecting the domain 4 (which corresponds to domain 7 in Arkov et al. [29]), whereas tudB42 in domain 7 (which corresponds to domain 10 in Arkov et al. [29]) completely abolishes germ cell formation [29].
Because mini-Tud Δ3, but not mini-Tud Δ1 protein, is able to support germ cell formation, the authors conclude that Tud localization to the nuage is not absolutely required for germ cell formation and that specific Tudor domains control Tud protein localization [29].
It has recently reported in cell cultures that the human Dazl functions in primordial germ cell formation, whereas Daz and Boule promote later stages of meiosis and development of haploid gametes [36], in accordance with their stage-specific expression [1].
