Oocyte maturation, the important process to produce female haploid gamete, accompanies with polarity establishment and highly asymmetric cell division to emit minor polar body within little cytoplasm. Microfilaments play central roles in polarity establishment and asymmetric cell division. Several actin regulators like WASP protein family as well as small GTPases function in microfilament dynam...

Fertilization involves cell-cell fusion of a sperm with the oocyte. This fusion restores the diploid genome, activates the oocyte, and initiates embryonic development. The identification of proteins mediating the fusion of sperm with oocyte plasma membrane (oolemma) is important to a deeper knowledge of fertilization. Defects in sperm-oocyte fusion may account for some form of human infertility...

We analyzed the expression of mRNAs for growth factor [epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I), basic fibroblast growth factor (bFGF) and platelet-derived growth factor A chain (PDGF-A)] and their receptor (R) by reverse transcription-polymerase chain reaction in bovine ova during oocyte maturation in vitro (0-21 hr) and after fertilization in vitro (6-144 hr: zygote...

BACKGROUND Recent studies suggest that ovarian germ line stem cells replenish oocyte-pool in adult stage, and challenge the central doctrine of 'fixed germ cell pool' in mammalian reproductive biology. Two distinct populations of spherical stem cells with high nucleo-cytoplasmic ratio have been recently identified in the adult mammalian ovary surface epithelium (OSE) including nuclear OCT-4A po...

Although it has been suggested that in mammals the loss of female germ cells may induce the masculinization of the ovarian compartment, there has been as yet no conclusive demonstration. To directly address that question, the present study has been designed to determine the fate of follicular cells after oocyte loss. Using gamma-irradiation to selectively deplete oocytes in nongrowing follicles...

Background: Since the sheep ‘Dolly’ was successfully cloned by somatic cell nuclear transfer (SCNT), the inefficiency of SCNT cloning and abnormality of cloned animals have been a focus of considerable controversy. Oocyte quality has been shown to contribute to poor somatic cloning and cell reprogramming efficiency with many factors affecting oocyte quality and developmental potential. It has b...

objective(s): umbilical cord blood-derived mesenchymal stromal cells (ucb-mscs) are ideally suited for use in various cell-based therapies. we investigated a novel induction protocol (nip) to improve the neuronal differentiation of human ucb-mscs under appropriate conditions. materials and methods: this experimental study was performed in iranian blood transfusion organization (ibto), tehran, i...

In mammals, immature oocytes are surrounded by a layer of flattened cells. At this early stage of development, these "follicle cells" and the plasma membrane of the oocyte are in close proximity. As the oocyte matures, the follicle cells multiply and become cuboidal or radially elongated, and a jelly-like substance containing polysaccharides (1) appears between the oocyte cortex and the follicl...