BACKGROUND Stage-specific embryonic antigen-1 (SSEA1) is a cell surface carbohydrate that its pattern expression is changed during induction of mouse embryonic stem cell differentiation. In this study, the spatial distribution of SSEA1 on primordial germ cells differentiation and subsequent progression into oocyte-like cells from mouse embryonic stem cells in vitro was evaluated. METHODS Embr...

Animal oocytes undergo a highly conserved developmental arrest in prophase of meiosis I. Often this marks a period of rapid growth for the oocyte and is necessary to coordinate meiotic progression with the developmental events of oogenesis. In Drosophila, the oocyte develops within a 16-cell germline cyst. Throughout much of oogenesis, the oocyte remains in prophase of meiosis I. By contrast, i...

Abdomen and germ cell development of Drosophila melanogaster embryo requires proper localization of oskar mRNA to the posterior pole of the developing oocyte. oskar mRNA localization depends on complex cell biological events like cell-cell communication, dynamic rearrangement of the microtubule network, and function of the actin cytoskeleton of the oocyte. To investigate the cellular mechanisms...

Background: Regulation of gene expression in mammalian embryos is not completely known. Pre-implantation embryos need maternal RNA and proteins synthesized during oogenesis, to regulate development before mater-embryo transition, as the grown oocyte and the 1-cell zygote are transcriptionally silent. There are some oocyte-specific genes called maternal effect genes which may account for this ea...

Oocyte meiosis and early mitotic divisions in developing embryos rely on the timely production of cell cycle regulators and their clearance via proteasomal degradation. Ret Finger Protein-Like 4 (Rfpl4), encoding a RING finger-like protein with a B30.2 domain, was discovered during an in silico search for germ cell-specific genes. To study the expression and functions of RFPL4 protein, we perfo...

Studies on cell fusion-mediated nuclear reprogramming have led to the breakthrough of the induced pluripotent stem (iPS) cell technology. While this technology has neared stem cells to applications more than any other method, the mechanistic bases of reprogramming remain largely unsolved. In this context, comparative studies of oocyte and cell fusion-mediated reprogramming hold the greatest pro...

BACKGROUND The LH surge promotes ovulation via activation of multiple signaling networks in the ovarian follicle. Studies in animal models have shown the importance of LH-induced activation of the epidermal growth factor (EGF)signaling network in critical peri-ovulatory events. We investigated the biological significance of regulatory mechanisms mediated by EGF-like growth factors during LH sti...

In the growing follicle, communication between the oocyte and its surrounding follicular cells is essential for normal oocyte and follicular development. Maturation of the fully grown oocyte in vivo is associated with the loss of cumulus cell-oocyte gap junctional communication, preventing entry of meiotic-modulating factors such as cAMP into the oocyte. We have previously shown that oocyte and...

Adult pancreatic stem cells (PSCs) are able to differentiate spontaneously in vitro into various somatic cell types. Stem cells isolated from rat pancreas show extensive self-renewal ability and grow in highly viable long-term cultures. Additionally, these cells express typical stem cell markers such as Oct-4, nestin and SSEA-1. Although differentiation potential is slightly decreasing in long-...

Previous studies indicate that stress damages oocytes with increased secretion of glucorticoids. However, although injection of female mice with cortisol decreased oocyte competence, exposure of mouse oocytes directly to physiological or stress-induced concentrations of glucorticoids did not affect oocyte maturation and embryo development. This study has explored the mechanisms by which glucoco...