The oocyte is the largest cell found in multicellular organisms. Mitochondria, as the energy factories for cells, are found in high numbers in oocytes, as they provide the energy for oocyte maturation, fertilization, and embryo formation via oxidative phosphorylation. Failure of assisted reproduction is mainly attributed to oocyte aging and increased aneuploidy. As the most numerous organelle i...

In women, oocytes arrest development at the end of prophase of meiosis I and remain quiescent for years. Over time, the quality and quantity of these oocytes decreases, resulting in fewer pregnancies and an increased occurrence of birth defects. We used the nematode Caenorhabditis elegans to study how oocyte quality is regulated during aging. To assay quality, we determine the fraction of oocyt...

We have studied the reconstitution of the Golgi apparatus in vivo using an heterologous membrane transplant system. Endogenous glycopeptides of rat hepatic Golgi fragments were radiolabeled in vitro with [3H]sialic acid using detergent-free conditions. The Golgi fragments consisting of dispersed vesicles and tubules with intraluminal lipoprotein-like particles were then microinjected into Xenop...

conclusions taken together, the combination of chemical and growth factors in the two-step induction protocol may improve the efficiency of msc differentiation into neural progenitor cells, and may be a new method for the easy and fast application of mscs in regenerative medicine in the future. results the results of real-time pcr showed that the expression of the gfap, mbp, and map-2 genes aft...

background: cryptorchidism is a common malformation in neonates; surgery or medical treatments are applied during childhood. untreated cryptorchid testes are in the risk of intratubular germ cell neoplasia (igcn) and consequently invasive testicular tumors which could be shown by immunohistochemistry staining for placental like acid phosphatase (plap) marker. objective: we designed this study t...

Molecular motors transport the axis-determining mRNAs oskar, bicoid and gurken along microtubules (MTs) in the Drosophila oocyte. However, it remains unclear how the underlying MT network is organized and how this transport takes place. We have identified a centriole-containing centrosome close to the oocyte nucleus. Remarkably, the centrosomal components, gamma-tubulin and Drosophila pericentr...

A fundamental rule of cell division is that daughter cells inherit half the DNA complement and an appropriate proportion of cellular organelles. The highly asymmetric cell divisions of female meiosis present a different challenge because one of the daughters, the polar body, is destined to degenerate, putting at risk essential maternally inherited organelles such as mitochondria. We have theref...

Electron-microscope observations on the differentiation of germ cells in Xenopus laevis have revealed that the Balbiani body, cytoplasmic nucleolus-like bodies and groups of mitochondria associated with granular material previously reported only in older amphibian oocytes, are also present in the primordial germ cells, oogonia and early meiotic (prediplotene) oocytes of this species. Although t...

Electron-microscope observations on the differentiation of germ cells in Xenopus laevis have revealed that the Balbiani body, cytoplasmic nucleolus-like bodies and groups of mitochondria associated with granular material previously reported only in older amphibian oocytes, are also present in the primordial germ cells, oogonia and early meiotic (prediplotene) oocytes of this species. Although t...