Molecular Biology of the Oocyte

性腺发生：雌性生殖细胞在第一次减数分裂的前期形成卵泡，在卵泡中它们被新生卵巢中的体细胞包围。这些卵泡生长和减数分裂期间的不对称细胞分裂确保了排卵的卵子含有成功发育所必需的母体因子。出生后的雄性生殖细胞在睾丸内维持精原干细胞生态位，从该生态位中选择群体进行减数分裂，并在精子发生期间转化为成熟精子。目前的研究调查了以下的作用：1）FIGLA，雌性小鼠中卵泡形成所需的生殖细胞特异性转录因子; 2）SSNP 1，维持精原干细胞所需的生殖细胞核蛋白;和3）BTBD 18，确保精子发生所需的粗线期皮尔纳表达的核蛋白。 施肥：哺乳动物精卵识别的分类特异性导致单精子受精，主要是由透明质膜介导的，透明质膜是排卵卵周围的细胞外基质。虽然是3-4个糖蛋白的简单结构，但这种精子与透明体结合的分子基础一直存在争议。目前的研究调查：1）支持在透明壳表面上分类群特异性精卵识别的分子要求; 2）导致配子融合所必需的顶体胞吐作用的机制; 3）防止受精后多精受精的过程。 早期发展：在小鼠卵细胞减数分裂成熟过程中终止的转录只有在两细胞胚胎的胚胎基因组被强烈激活后才能恢复。卵母细胞和胚胎基因转录之间的空隙决定了储存的母体因子的作用。使用小鼠转基因，在这些过程中，个别或复杂的母体因素的作用进行了研究。目前的研究调查：1）影响小鼠早期发育的新的母体效应基因; 2）母体细胞器在母体向合子转变中的作用; 3）母体成分在胚胎基因组激活中的降解。

Gonadogenesis: Female germ cells arrested at the prophase of the first meiotic division form follicles in which they are surrounded by somatic cells in the neonatal ovary. These follicles grow and asymmetrical cell division during meiosis ensures that ovulated eggs contain maternal factors necessary for successful development. Post-natal male germ cells maintain a spermatogonia stem cell niche within the testis from which cohorts are selected to undergo meiosis and are transmogrified into mature spermatozoa during spermiogenesis. Current studies investigate the roles of: 1) FIGLA, a germ cell specific transcription factor required for follicle formation in female mice; 2) SSNP1, a germ cell nuclear protein required for maintenance of spermatogonia stem cells; and 3) BTBD18, a nuclear protein that ensures pachytene piRNA expression necessary for spermiogenesis. Fertilization: The taxon-specificity of sperm-egg recognition in mammals that results in monospermic fertilization is mediated primarily by the zona pellucida, an extracellular matrix surrounding ovulated eggs. Although a simple structure of 3-4 glycoproteins, the molecular basis of this sperm binding to the zona pellucida has been controversial. Current studies investigate: 1) molecular requirements to support taxon-specific sperm-egg recognition on the surface of the zona pellucida; 2) mechanism that result in acrosome exocytosis necessary for gamete fusion; and 3) the processes by which post-fertilization polyspermy is prevented. Early Development: Transcription that terminates during meiotic maturation of mouse eggs resumes only after robust activation of the embryonic genome of the two-cell embryo. This interregnum between oocyte and embryonic gene transcription dictates a role for stored maternal factors. Using mouse transgenesis, the role of individual or complexes of maternal factors is studied in these processes. Current research investigates: 1) novel maternal effect genes that affect early mouse development; 2) the role of maternal organelles in the maternal to zygotic transition; and 3) the degradation of maternal components in activation of the embryonic genome.