Sexually Dimorphic Regulation Of SF-1 In Gonadogenesis

描述(申请人提供)：类固醇生成因子-1(SF-1)在内分泌功能和性腺发育中发挥关键作用。事实上，携带SF-1基因突变的人类患者是性别颠倒的，缺乏正常的性腺结构，并患有严重的肾上腺功能不全。SF-1基因敲除的小鼠也有性腺和肾上腺发育不全。SF-1在性腺分化中的性别特异性作用尚不清楚，因为在SF-1基因突变的动物中，性腺在性别决定开始之前就已经丢失。这项建议的主要目标是确定SF-1在小鼠性腺发育过程中的性别特异性功能。为了研究SF-1在两性性腺发育中的作用，我们开发了一种技术，将核酸引入到泌尿生殖道脊中，并监测随后的培养结果。我们的总体假设是，SF-1的性别二型性表达模式对于男性和女性性腺发生是不可或缺的，并且是由SF-1启动子的性别特异性调节引起的。首先，我们将通过靶向男性性腺外植体培养中针对SF-1的siRNA来确定SF-1错误表达的后果(目标1)。其次，我们将评估男性和女性性腺外植体培养中SF-1的5‘调控区，以确定是否存在针对该基因性别特异性表达的特定元件(目标2)。我们已经有效地消除了siRNA处理的性腺中SF-1的存在，并成功地将SF-1启动子的构建靶向了男性和女性中正确的细胞类型。这些研究是已知的第一次尝试研究SF-1在活体、完整、功能正常的性腺发育过程中的作用机制。这些研究的结果将对我们目前对SF-1在性腺发育过程中功能的理解产生深远的影响。此外，这种方法将使科学家能够开始对已知和未知的基因进行新的研究，这将导致性腺生成领域的重大进展，并为治愈包括出生缺陷、不育和癌症在内的性腺异常提供希望。

DESCRIPTION (provided by applicant): Steroidogenic factor-1 (SF-1) plays pivotal roles in endocrine function and gonad development. Indeed, human patients with mutations in SF-1 are sex-reversed, lack normal gonad structure, and suffer from severe adrenal insufficiency. The SF-1 knock out mouse also has agenesis of gonads and adrenal glands. Sex-specific roles of SF-1 in gonad differentiation remain unknown because gonads in SF-1 disrupted animals are lost before the onset of sex determination. The main goal of this proposal is to identify the sex-specific functions of SF-1 during mouse gonad development. To examine the role of SF-1 during gonad development in both sexes, we have developed a technique to introduce nucleic acids into the urogenital ridge and monitor the ensuing consequences in culture. Our overall hypothesis is that the sexually dimorphic expression pattern of SF-1 is integral for male versus female gonadogenesis and is caused by sex-specific regulation of the SF-1 promoter. First, we will determine the consequences of SF-1 misexpression by targeting siRNAs specific for SF-1 in explant cultures of male gonads (Aim 1). Second, we will evaluate the 5' regulatory region of SF-1 in male and female gonad explant cultures to ascertain whether there are specific elements that target sex-specific expression of the gene (Aim 2). We have effectively eliminated the presence of SF-1 in siRNA treated gonads and have successfully targeted SF-1 promoter constructs to the correct cell types in males and females. These studies are the first known attempt to investigate the mechanism of SF-1 action in a live, intact, functioning gonad as it is developing. Findings resulting from these studies will have a profound impact on our current understanding of SF-1 function during gonad development. Furthermore, this method will enable scientists to embark on new studies on genes, known and unknown, that will lead to significant advances in the field of gonadogenesis and provide hope for a cure of gonadal anomalies including birth defects, infertility, and cancers.