IDENTIFICATION/CHARACTERIZATION OF NOVEL MATERNAL-EFFECT GENE PRODUCTS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 卵母细胞衍生的基因产物指导发生在卵母细胞到胚胎转变的一系列关键事件，包括第一次减数分裂的完成、第二次减数分裂的开始和胚胎基因组的激活。 这些基因产物中只有少数被称为母体效应蛋白，已经被鉴定，并且对介导其功能的机制知之甚少。 我们通过计算机减法鉴定了几个新的潜在的母体效应基因。在对小鼠和猕猴的基因表达进行初步分析后，我们决定将重点放在一个新发现的蛋白质家族--NLR家族，pyrin domain containing protein（NLRP）上。这个家庭中的大多数成员的功能是未知的。然而，几个Nlrp基因只存在于啮齿动物的生殖细胞中;其中至少有一个NLRP 5对小鼠早期胚胎发育至关重要。基于先前在小鼠中的发现和我们在猕猴中的初步数据，我们假设卵母细胞特异性NLRP是卵母细胞成熟、受精和早期胚胎发育所必需的;因此，敲低猕猴卵母细胞中的一个或多个NLRP基因将损害卵母细胞向胚胎过渡的进展，导致未受精卵或植入前胚胎的发育停滞。为了进一步表征猕猴卵母细胞特异性NLRP，我们建议证明NLRP蛋白的时空表达，并在卵母细胞中使用体外RNA干扰（RNAi）进行功能研究。此外，我们将产生Nlrp基因敲除/敲低小鼠模型，以探索其在啮齿动物体内的功能。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Oocyte-derived gene products direct a series of crucial events occurring at the oocyte-to-embryo transition, including the completion of the first meiosis, the initiation of the second meiosis, and the activation of the embryo genome. Only a few of these gene products, termed maternal effect proteins, have been identified and little is known about the mechanisms mediating their functions. We identified several novel potential maternal effect genes by in silico subtraction. After initial gene expression analysis in mice and macaques, we decided to focus on a newly described protein family--NLR family, pyrin domain containing protein (NLRP). The function of the majority members in this family is unknown. However, several Nlrp genes are found exclusively in germ cells in rodents; and at least one of them, NLRP5, is essential to early embryo development in mice. Based on previous findings in mice and our preliminary data in macaques, we hypothesize that oocyte-specific NLRPs are required for oocyte maturation, fertilization, and early embryo development; thus, knocking down one or more NLRP genes in the macaque oocyte will impair the progress of oocyte-to-embryo transition, resulting in unfertilizable eggs or developmental arrest of preimplantation embryos. To further characterize oocyte-specific NLRPs in macaques, we propose to demonstrate the spatiotemporal expression of NLRP proteins and perform functional studies using in vitro RNA interference (RNAi) in the oocyte. In addition, we will generate Nlrp gene knockout/knockdown mouse models to explore their in vivo functions in rodents.