Molecular and cellular control of oocyte maturation in mammals

产生健康受精卵的能力对于繁殖是必不可少的。与卵子发育相关的问题是不孕不育和早期胚胎丢失(流产)的主要原因。卵子如此脆弱的原因之一是它们经历了一个被称为减数分裂的特殊过程。这一过程始于胎儿时期，直到卵子受精后才结束；在某些情况下是40多年后。此外，女性出生时就拥有了其生殖寿命所需的所有卵子；不能产生新的卵子。在减数分裂中，卵在不同的阶段停止和开始，但其生命的大部分时间都在所谓的？休眠？卵巢中的状态。在某个时间点，卵子开始生长，直径增加5倍，体积增加约300倍，成为体内最大的细胞之一(直径为十分之一毫米)。在所有这一过程中，卵子仍处于发育停滞状态，直到排卵前，卵子才继续减数分裂，染色体数量减半。这种减数分裂很容易出错，这是随着女性年龄的增长，特别是40岁以上，生育率大幅下降的唯一主要原因。我们正在使用老鼠的卵子试图了解减数分裂是如何工作的，这样我们就可以更多地了解如何保持卵子在卵巢中保持健康，以及它们如何顺利通过减数分裂，而不会出现导致低质量胚胎的错误。我们的研究进展通过科学期刊、专家网站和向主流媒体发布的新闻稿进行交流。通过这种方式，我们的目标是让科学家、那些有特殊兴趣的人和公众了解我们由MRC资助的研究。

The ability to produce a healthy fertile egg is essential for reproduction. Problems associated with the development of eggs are a major cause of infertility and early embryo loss (miscarriage). One of the reasons why eggs are so vulnerable is that they go through a specialised process known as meiosis. This process starts during foetal life and does not finish until after the egg is fertilized; more than 40 years later in some cases. Furthermore, women are born with all the eggs that will be available for her reproductive lifespan; no new eggs can be made. In meiosis the egg stops and starts at different stages but spends most of its life in a so-called ?dormant? state in the ovary. At some point the egg starts to grow increasing in diameter by 5 fold and in volume by about 300 fold to become one of the largest cells in the body (one-tenth of a millimetre across). Through all of this process the egg remains arrested in development and it is not until just before ovulation that the egg continues meiosis and halves the number of chromosomes. This meiotic division is prone to errors and is the single main reason why there is such a dramatic decrease in fertility as women get older, particularly over the age of 40. We are using mouse eggs to try to understand how meiosis works so that we can understand more about how to keep eggs arrested and healthy in the ovary and how they can go through the meiotic division without errors that cause poor quality embryos. Advances in our research are communicated in scientific journals, specialist websites and by press releases to the mainstream media. This way we aim to keep scientists, those with special interest and the public aware of our MRC funded research.