KLHL25-eIF4E通路在原发性卵巢功能不全发病中的作用及机制研究

Premature ovarian insufficiency (POI) is a complex disorder known to be highly heterogeneous both in phenotype and etiology. The genetic factor is an important component of POI, and whole exome sequencing (WES) has been proven invaluable in discovery of novel POI causative genes. We performed WES in a non-consanguineous early menopause and POI family, and identified KLHL25 as the potential gene. All patients carried a novel frameshit mutation p.D84Mfs*69 of the KLHL25 gene, which may result in a truncated protein and loss of function. KLHL25 binds to CUL3 as an E3 ubiquitin ligase and targets the ubiquitination and degradation of hypophosphorated eIF4EBP1, thus increases the level of eIF4E and improves the initiation of translation. There has been no related study about the role KLHL25 in ovarian disorders. Based on previous data, we will perform Sanger sequencing of KLHL25 in sporadic POI patients to verify the contribution of KLHL25 in the etiology of POI, and further explore the possible deleterious effect of KLHL25 mutations on ovarian function both in vivo and in vitro. These results will give more insight into the complex gene network involved in POI.

原发性卵巢功能不全(POI)是一种临床表现复杂、病因不清、进展迅速、缺乏有效治疗方法的生殖障碍性疾病，不仅导致不孕不育，而且易继发多种慢性疾病。遗传因素是POI的主要发病机制之一，全外显子组测序是发现致病基因的有效手段。课题组前期对一罕见早绝经/POI家系进行全外显子组测序，发现潜在致病基因KLHL25发生移码突变p.D84Mfs*69。KLHL25与E3泛素连接酶CUL3结合，提高活性eIF4E的水平，促进翻译起始，但与卵巢相关疾病的研究尚未见报道。本项目拟在前期研究基础上，在散发POI患者中进一步验证KHLH25基因的致病性及突变频率；同时借助体内外功能实验探讨突变p.D84Mfs*69对颗粒细胞、膜细胞功能、卵泡发育以及生殖储备的影响，明确KLHL25-eIF4E通路在POI发生发展中的作用，为POF病因学研究提供新的科学依据和临床证据。

原发性卵巢功能不全(POI)是一种临床表现复杂、病因不清、进展迅速、缺乏有效治疗方法的生殖障碍性疾病，不仅导致不孕不育，而且易继发多种慢性疾病。遗传因素是POI的主要发病机制之一，本项目重点关注导致卵泡耗竭加速的遗传因素，从临床患者出发，通过全外显子组测序、Sanger测序发现潜在致病变异，并借助体外实验和动物模型等技术手段开展致病机制探索。通过分析大样本POI患者全外显子组测序数据，本项目在POI病人中发现了PRDM9、ANKRD31、EXO1以及RAD51基因潜在致病变异；对散发POI患者直接测序发现FANCL、FAM175A以及TLK1等基因杂合变异。进一步通过体内外功能实验，证实了上述基因变异在POI发病中的作用及机制。研究发现进一步丰富了POI致病基因谱，拓展了卵泡耗竭加速的遗传学致病机制，为POI病因学研究提供了新的科学依据和临床证据。