精子SSP411缺失表达致早胚卵裂延迟的分子机制

项目名称： 精子SSP411缺失表达致早胚卵裂延迟的分子机制

项目编号： No.81471503

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 施惠娟

作者单位： 上海市计划生育科学研究所

项目金额： 78万元

中文摘要： ssp411是我们克隆的一个新基因，特异地在性成熟大鼠、小鼠和人睾丸及附睾精子中表达，但其功能尚不清楚。我们前期研究发现，该基因敲除小鼠雌性正常而雄性不育，表现为精子少、弱。受精卵的快速有丝分裂称为卵裂，一般认为卵裂速度主要与卵质有关。有趣的是，我们通过ICSI发现，精子缺失ssp411致早胚卵裂异常，提示该基因可能是一个激活卵裂的精子因子。在本申请项目中，我们将利用基因敲除小鼠模型，进一步鉴定SSP411在早胚卵裂中的功能；利用自制单抗免疫共沉淀鉴定其相互作用蛋白，深入研究SSP411的分子机制；通过鉴定启动子DNA甲基化模式等研究该基因的表达调控。此外，我们发现约7%不育男性精子中SSP411表达低或缺失，我们将进一步鉴定该基因在不育患者精子中沉默的分子机制、异种受精研究其在人卵裂中的功能机制。项目研究获得结果将揭示精子蛋白SSP411调控卵裂的分子机制，并为相关不育症提供新诊治方法。

中文关键词： 男性不育；男性生殖；分子机制；精子功能

英文摘要： ssp411 is a novel gene cloned from rat in our lab, its gene products (mRNA and protein) could be detected specially in spermatids and mature sperms of rat, mouse and human. Our previous studies indicate female ssp411 knock-out mice are fertile, while males suffer from oligo-asteno-teratozoospermia and sterility. Cleavage is a period of rapid division of zygote, the early activities of cleavage is generally thought to be governed by mother's genomic products deposited in the egg. However, we find that ssp411-defect sperms could fertilize mouse eggs via ICSI procedure, but delay the subsequent cleavage of zygote, which suggests that ssp411 is a possible sperm factor that can activate cleavage. In this project, we will carry out following basic studies: 1) by using ssp411-defect mouse model, we will evaluate the detailed functions of ssp411 on cleavage of early embryo; 2) with monoclonal antibody prepared in our lab, the project will study the molecular mechanism of function of SSP411 protein; 3)via molecular biology stretagies,such as methylation profiling of promoter by pyrosequencing, we will study the expression regulation of ssp411 gene. Moreover, we screen samples in our human sperm bank, and find that loss or low level of SSP411 occurrs in 7% of sterile males. With these sperm samples, we will study the silence mechanism of human ssp411 gene and its functions on human zygote cleavage. This project will elucidate the molecular mechanism of male sterility caused by ssp411 defect, and provide novel diagnostic and therapeutic strategies for clinic approaches.

英文关键词： male infertility;male reproduction;molecular mechanism;sperm function