Various morphological and cytological traits of oocytes and their surrounding cumulus cells may be used to select oocytes for assisted reproduction. However, even with careful selection, successful IVF and subsequent embryo development remain uncertain. The factors that ensure oocyte competence are unclear and other approaches to assessing developmental potential must be explored. With the cons...

The checkpoint proteins, Rad9, Rad1, and Hus1 (9-1-1), form a complex which plays a central role in the DNA damage-induced checkpoint response. Previously, we demonstrated that Drosophilahus1 is essential for activation of the meiotic checkpoint elicited in double-strand DNA break (DSB) repair enzyme mutants. The hus1 mutant exhibits similar oocyte nuclear defects as those produced by mutations...

Cyclin-dependent kinase 1 (CDK1) is a major M-phase kinase which requires the binding to a regulatory protein, Cyclin B, to be active. CDK1/Cyclin B complex is called M-phase promoting factor (MPF) for its key role in controlling both meiotic and mitotic M-phase of the cell cycle. CDK1 inactivation is necessary for oocyte activation and initiation of embryo development. This complex process req...

During Drosophila oogenesis Gurken, associated with the oocyte nucleus, activates the Drosophila EGF receptor in the follicular epithelium. Gurken first specifies posterior follicle cells, which in turn signal back to the oocyte to induce the migration of the oocyte nucleus from a posterior to an anterior-dorsal position. Here, Gurken signals again to specify dorsal follicle cells, which give r...

The onset of development is marked by two major, posttranscriptionally controlled, events: oocyte maturation (release of the prophase I primary arrest) and egg activation (release from the secondary meiotic arrest). Using quantitative mass spectrometry, we previously described proteome remodeling during Drosophila egg activation. Here, we describe our quantitative mass spectrometry-based analys...

a:4:{s:10:"Background";s:1707:"Early embryonic development in mammals begins in transcriptional silence with an oocyte-mediated transcriptional reprogramming of parental gametes occurs during a so called across-the-board process of “erase-and-rebuild”. In this process, the parental transcription programs are erased long before (maternal) or soon thereafter (paternal) fertilization to generate a...

Fluorescein-labeled rabbit serum globulin was injected into vitellogenic oocytes of the cecropia moth. Though the label spread throughout the ooplasm in less than 30 min, it was unable even after 2 h to cross the complex of intercellular bridges connecting the oocyte to its seven nurse cells. After injection into a single nurse cell, fluorescence was detected in the oocyte adjacent to the bridg...

Background: Polycystic ovary syndrome (PCOS) is a frustrating experience for women, considered as a complex challenge for researchers and clinicians. Despite the enormous effort to define the cause of PCOS, the etiology and pathogenesis still remain unclear. Oocyte quality is reflected in the oocyte’s intrinsic developmental potential. Studies have shown that the follicular development is disru...