Use of a Fragile X premutation knock-in mouse to study FXPOI

使用 Fragile X 前突变敲入小鼠研究 FXPOI

• 批准号: 8512519
• 负责人: GLORIA E HOFFMAN
• 金额: $ 25.08万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-06 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8512519
• 关键词: 5' Untranslated Regions; Accounting; Address; Affect; Age; Age-Months; Alleles; Alzheimer' s Disease; Animals; Apoptotic; Biochemical; CGG repeat; Cell Communication; Cell Count; Cell Death; Cell Nucleus; Cell Proliferation; Cells; Cessation of life; Communication; Connexins; Coupled; Cyst; Data; Development; Diagnosis; Employee Strikes; Event; Exhibits; FMR1; FMR1 Gene; FMR1 Premutation; Female; Fertility; Fragile X Mental Retardation Protein; Fragile X Premutation; Fragile X Syndrome; Frequencies; Functional disorder; Future; Gap Junctions; Gene Expression; Genes; Genotype; Glycoconjugates; Gonadotropins; Growth and Development function; Hematoxylin and Eosin Staining Method; Hormonal; Human; Hypothalamic structure; Incidence; Infertility; Knock-in Mouse; Lead; Learning; Link; Location; Longevity; Menopause; Mitotic; Modeling; Molecular; Monitor; Morphology; Mus; Mutate; Neurosecretory Systems; Nuclear; Oocytes; Osteoporosis; Ovarian; Ovarian Follicle; Ovary; Pathology; Phenotype; Physiology; Pituitary Gland; Premenopause; Process; Production; Proteins; Puberty; Risk; Siblings; Somatic Cell; Source; Staging; Staining method; Stains; Testing; Transplantation; Turner' s Syndrome; Ubiquitin; Woman; Work; X Chromosome; Zona Pellucida; cardiovascular disorder risk; corpus luteum; glycosylation; granulosa cell; inhibin; mouse model; mullerian-inhibiting hormone; ovary transplantation; premature; public health relevance; stem; tool

DESCRIPTION (provided by applicant): FMR1 is a gene on the X chromosome that contains an expansion-prone CGGCCG repeat in its 5' untranslated region. Alleles with 55-200 repeats are considered to be Fragile X premutation (PM) alleles. The frequency of such alleles in women ranges from 1 in 113 to 1 in 250. Carriers of such alleles are at risk for Fragile X Primary Ovarian Insufficiency (FXPOI) that is seen in up to 28% of women who carry such alleles. FXPOI accounts for ~11.5% of familial cases of infertility and 3.5% of idiopathic cases. Even without a diagnosis of FXPOI, the average age at menopause of all women with the premutation is ~5 yrs earlier than their siblings without the PM. Thus, female PM carriers not only have increased fertility problems, but are at greater risk of cardiovascular disease, Alzheimer disease, osteoporosis and other problems that are seen at higher frequency in menopausal women. Hormonal assessment of PM carriers indicates that FSH is elevated, inhibins and anti-Mullerian hormone (both made by granulosa cells) are reduced. Preliminary data from a knock-in Fragile X PM mouse model containing ~130 CGG repeats suggest a number of ovarian problems. These include early losses of immature follicles and reductions in corpora lutea. Advanced follicles were smaller in PM mice and showed a higher rate of atresia. This was associated with a smaller than normal number of granulosa cells (GCs). In addition, PM oocytes showed abnormal nuclear morphology, reduced levels of gap junction proteins, abnormal staining of their zona pellucida, a primarily nuclear location of the normally cytoplasmic fragile X mental retardation protein (FMRP) and high levels of ubiquitinated proteins that often accumulated in the nucleus or perinuclear region. A high incidence of large cysts was also seen in PM mice. Thus our mice exhibit signs consistent with ovarian insufficiency and have unusual ovarian changes that could contribute to this ovarian dysfunction. These mice may therefore provide a good model of FXPOI. Aim 1 uses transplantation approaches to address whether the PM in the ovary alone is sufficient to produce the FXPOI-like and aberrant ovarian features or instead requires the PM in the hypothalamic/pituitary unit. Aim 2 focuses on the abnormal FMRP, ubiquitin, and gap junctions as well as the abnormalities in zona pellucida composition to attempt to uncover the mechanism(s) responsible for the follicle decline.

描述（由申请人提供）： FMR 1是X染色体上的一个基因，包含一个易于扩增的CGGCCG重复序列在其5'非翻译区。具有55-200个重复的等位基因被认为是脆性X前突变（PM）等位基因。这种等位基因在女性中的频率范围从1/113到1/250。这些等位基因的携带者有患脆性X原发性卵巢功能不全（FXPOI）的风险，在携带这些等位基因的女性中高达28%。FXPOI占不孕症家族性病例的11.5%，占特发性病例的3.5%。即使没有FXPOI的诊断，所有具有前突变的女性的平均绝经年龄也比没有PM的兄弟姐妹早约5年。因此，女性PM携带者不仅具有增加的生育问题，而且具有更大的心血管疾病、阿尔茨海默病、骨质疏松症和在绝经期妇女中更高频率出现的其他问题的风险。PM携带者的激素评估表明FSH升高，卵泡刺激素和抗苗勒管激素（均由颗粒细胞产生）减少。来自含有~130个CGG重复序列的敲入脆性X PM小鼠模型的初步数据表明存在许多卵巢问题。这些包括未成熟卵泡的早期丢失和黄体减少。PM小鼠的晚期卵泡较小，闭锁率较高。这与颗粒细胞（GC）数量少于正常值有关。此外，PM卵母细胞显示异常的核形态，减少水平的间隙连接蛋白，异常染色的透明质酸，一个主要的核位置的正常细胞质脆性X智力低下蛋白（FMRP）和高水平的泛素化蛋白，往往积累在细胞核或核周区域。在PM小鼠中也观察到大囊肿的高发病率。因此，我们的小鼠表现出与卵巢功能不全一致的体征，并且具有可能导致这种卵巢功能障碍的不寻常的卵巢变化。因此，这些小鼠可以提供FXPOI的良好模型。目的1使用移植方法来解决是否在卵巢中单独的PM是足以产生FXPOI样和异常的卵巢功能，而是需要在下丘脑/垂体单位的PM。目的2：研究卵泡发育过程中FMRP、泛素、缝隙连接以及透明质酸组成的异常，试图揭示卵泡发育过程中卵泡功能下降的机制。