Oocyte maturation depends on multiple variables. In fact, in dogs, the requirements for oocyte development in vitro are so complex that achievement of female gamete maturation has been viewed as a difficult problem. The conundrum, thus far unanswered, of achieving dog oocyte maturation in vitro, is nowadays the major puzzle of the in vitro program in the canine species. In in vitro studies of d...

BACKGROUND Oocyte maturation in lower vertebrates is triggered by maturation-inducing hormone (MIH), which acts on unidentified receptors on the oocyte surface and induces the activation of maturation-promoting factor (MPF) in the oocyte cytoplasm. We previously described the induction of oocyte maturation in fish by an endocrine-disrupting chemical (EDC), diethylstilbestrol (DES), a nonsteroid...

Fertility depends on germline stem cell proliferation, meiosis and gametogenesis, yet how these key transitions are coordinated is unclear. In C. elegans, we show that GLP-1/Notch signaling functions in the germline to modulate oocyte growth when sperm are available for fertilization and the major sperm protein (MSP) hormone is present. Reduction-of-function mutations in glp-1 cause oocytes to ...

The anterior-posterior axis of Drosophila originates from two symmetry-breaking steps during early oogenesis. First, one of the two pro-oocytes within the cyst of 16 germline cells is selected to become the oocyte. This cell then comes to lie posterior to the other germline cells of the cyst, thereby defining the polarity of the axis. Here we show that the oocyte reaches the posterior of the cy...

Wolbachia bacteria are widespread, maternally transmitted endosymbionts of insects. Maintenance of sufficient Wolbachia titer in maternal germline cells is required for transmission efficacy. The mechanisms that regulate Wolbachia titer are not well understood; however, dietary sucrose was reported to elevate oocyte Wolbachia titer in Drosophila melanogaster whereas dietary yeast decreased oocy...

Glucose is an essential nutrient for mammalian cells. Emerging evidence suggests that glucose within the oocyte regulates meiotic maturation. However, it remains controversial as to whether, and if so how, glucose enters oocytes within cumulus-oocyte complexes (COCs). We used a fluorescent glucose derivative (6-NBDG) to trace glucose transport within live mouse COCs and employed inhibitors of g...

Polyadenylation-induced translation is an important regulatory mechanism during metazoan development. During Xenopus oocyte meiotic progression, polyadenylation-induced translation is regulated by CPEB, which is activated by phosphorylation. XGef, a guanine exchange factor, is a CPEB-interacting protein involved in the early steps of progesterone-stimulated oocyte maturation. We find that XGef ...

To elucidate the molecular mechanisms underling hydration during oocyte maturation, we characterized the structure of Japanese eel (Anguilla japonica) novel-water selective aquaporin 1 (AQP1b) that thought to be involved in oocyte hydration. The aqp1b cDNA encodes a 263 amino acid protein that includes the six potential transmembrane domains and two Asn-Pro-Ala motifs. Reverse transcription-pol...

The differentiation of the female gamete into a developmentally competent oocyte relies on the protected environment of the ovarian follicle. The oocyte plays a key role in establishing this microenvironment by releasing paracrine factors that control the functions of surrounding somatic cells. Growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are secreted during ...

Citrinin is one of the mycotoxins and has been shown to have various toxic effects in animals and humans. Although previous study showed the toxic effects of citrinin on the female reproductive system, especially on oocyte maturation, however, the causes or mechanism of citrinin on oocyte quality is unclear. In present study we deeply investigated this topic. We found thatcitrinin toxin exposur...