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  • mRNA
  • Mutation of one of the two putative CaMKII phosphorylation sites in caspase-2 prevented the G6P- and NADPH-stimulated phosphorylation of caspase-2, and this mutant caspase-2 also promoted cell death of oocytes when its mRNA was injected into the oocytes. (sciencemag.org)
  • The injection of RNA into living cells: The use of frog oocytes for the assay of mRNA and the study of the control of gene expression. (springer.com)
  • eggs
  • Oocyte death ultimately leads to sterility as the animals age and conditions that accelerate death of the eggs cause premature infertility. (sciencemag.org)
  • Quality of the eggs (oocytes) may also be impaired as a 1989 study by Scott et al. (wikipedia.org)
  • embryonic
  • Frozen-thawed oocytes could be also later used for producing live offspring for faster multiplication of superior germplasm or for use in reproductive technologies like production of cloned or transgenic livestock or production of embryonic stem cells. (springer.com)
  • Thus, oocytes of many organisms are protected from oxidative DNA damage while storing up a large mass of substances to nurture the zygote in its initial embryonic growth. (wikipedia.org)
  • The oocyte receives mitochondria from maternal cells, which will go on to control embryonic metabolism and apoptotic events. (wikipedia.org)
  • Retrieval
  • There are significantly improved outcomes when women are exposed to seminal plasma around the time of oocyte retrieval, with statistical significance for clinical pregnancy, but not for ongoing pregnancy or live birth rates with the limited data available. (wikipedia.org)
  • Performing ultrasound-guided oocyte retrieval: RCN guidance for fertility nurses" (PDF). (wikipedia.org)
  • embryo
  • The oocyte, a large and complex cell, must be supplied with numerous molecules that will direct the growth of the embryo and control cellular activities. (wikipedia.org)
  • While the nucleolus is dense and inactive in a mature oocyte, it is required for proper development of the embryo. (wikipedia.org)
  • sperm
  • Both clinical trials and observational studies have compared reproductive outcomes after IVF and intracytoplasmic sperm injection (ICSI) with cryopreserved oocytes to IVF and ICSI with fresh oocytes. (acog.org)
  • Mouse sperm, however, are significantly different from sperm of most other mammals because they do not contribute a cellular organelle known as a centrosome to the fertilized oocyte. (scienceblog.com)
  • In a paper scheduled for publication in Biology of Reproduction, the team headed by Xiangzhong Yang of the Center for Regenerative Biology at the University of Connecticut, Storrs, and Ryuzo Yanagimachi of the University of Hawaii Medical School, Honolulu, reports that one rabbit pup was born after 230 oocytes fertilized with freeze-dried sperm were transferred to 8 female rabbits. (scienceblog.com)
  • Sperm entry causes calcium release into the oocyte. (wikipedia.org)
  • IP3 and DAG are produced from the cleavage of PIP2 by phospholipase C. However, another hypothesis is that a soluble 'sperm factor' diffuses from the sperm into the egg cytosol upon sperm-oocyte fusion. (wikipedia.org)
  • Once PLCζ is introduced into the oocyte by the sperm cell, it cleaves phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2) into diacyl glycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). (wikipedia.org)
  • ovaries
  • Poor ovarian reserve is a condition of low fertility characterized by 1): low numbers of remaining oocytes in the ovaries or 2) possibly impaired preantral oocyte development or recruitment. (wikipedia.org)
  • Thus
  • Thus, these results define a path from metabolic status through the pentose-phosphate pathway that controls oocyte cell survival in a process that relies on the phosphorylation state of caspase-2. (sciencemag.org)
  • frozen
  • Outcomes of four published randomized controlled trials demonstrated that fresh and frozen oocytes yield similar pregnancy rates in IVF cycles, supporting the use of these technologies in well-selected patients aged 35 years and younger ( 8-11 ). (acog.org)
  • Several studies have indicated that a more advanced age of the oocyte when frozen or vitrified reduces the odds of success when vitrified oocytes are used for IVF or ICSI. (acog.org)
  • ovocyte
  • An oocyte (UK: /ˈoʊəsʌɪt/, US: /ˈoʊ.oʊ.saɪt/), oöcyte, ovocyte, or rarely ocyte, is a female gametocyte or germ cell involved in reproduction. (wikipedia.org)
  • spindle
  • The damage (depolymerization) and/or absence of the spindle compromise the ability of the oocyte to fertilize and undergo normal preimplantation development. (hindawi.com)
  • undergo
  • Vertebrate females produce their full complement of oocytes during embryogenesis and, over time, these are either released (and fertilized or not) or undergo cell death. (sciencemag.org)
  • follicles
  • This increases the likelihood of the small follicles and oocytes therein developing normally for upcoming cycles and also allows the woman to cycle without taking a break and consequently increases the probability of conception in poor ovarian reserve women and advanced reproductive aged women. (wikipedia.org)
  • Mammals
  • In certain organisms, such as mammals, paternal mitochondria brought to the oocyte by the spermatozoon are degraded through the attachment of ubiquitinated proteins. (wikipedia.org)
  • In mammals, the nucleolus of the oocyte is derived solely from maternal cells. (wikipedia.org)
  • Vesicles
  • The overall outward-directed movement of the vesicle-actin network is driven by recruitment of vesicles to the plasma membrane in the periphery of the oocyte. (warwick.ac.uk)
  • In most cells, this occurs at the cell membrane however, evidence suggests that the PIP2 required for oocyte activation is potentially stored in intracellular vesicles dispersed throughout the cytoplasm. (wikipedia.org)
  • Inhibition
  • Inhibition of G6P dehydrogenase by dehydroisoandrosterone (DHEA), which inhibits the pentose-phosphate pathway, promoted oocyte cell death, increased the rate at which caspase activity rose in the egg extracts, and decreased the concentration of G6P and NADPH production. (sciencemag.org)
  • mRNAs
  • During the growth of the oocyte, a variety of maternally transcribed messenger RNAs, or mRNAs, are supplied by maternal cells. (wikipedia.org)
  • These mRNAs can be stored in mRNP (message ribonucleoprotein) complexes and be translated at specific time points, they can be localized within a specific region of the cytoplasm, or they can be homogeneously dispersed within the cytoplasm of the entire oocyte. (wikipedia.org)
  • Below are some examples of maternally inherited mRNAs and proteins found in the oocytes of the African clawed frog. (wikipedia.org)
  • Metabolic
  • L. K. Nutt, S. S. Margolis, M. Jensen, C. E. Herman, W. G. Dunphy, J. C. Rathmell, S. Kornbluth, Metabolic regulation of oocyte cell death through the CaMKII-mediated phosphorylation of caspase-2. (sciencemag.org)
  • If this metabolic activity were carried out by the oocyte's own metabolic machinery, the oocyte genome would be exposed to the reactive oxidative by-products generated. (wikipedia.org)
  • yolk
  • yolk contained in the oocytes of different animal species varies greatly in amount and distribution, which influences the pattern of the cleavage divisions. (thefreedictionary.com)
  • 2002
  • Maclellan LJ, Carnevale EM, Da Silva MC, Scoggin CF, Bruemmer JE, Squires EL (2002) Pregnancies from vitrified equine oocytes collected from super-stimulated and non-stimulated mares. (springer.com)