Developmental Differences in Brain Androgen Synthesis

描述(申请人提供)：斑马雀鸣唱系统由以下部分组成 性二形核。早期雌激素治疗使端脑变得男性化 遗传女性的宋氏核，但阻断雌激素不会去血管化 这些核存在于遗传雄性体内。研究表明，存在一种 大脑固有的遗传因素是歌曲男性化模式的基础 系统组织。最近，人们看到了性别差异 17α羟基酶(CyP17)的转录水平，这种酶能使 雄激素，在发育中的斑雀的端脑中。这是假设的 Gyp 17的表达延续到歌曲的类固醇敏感期 系统发育，并分布在宋核附近。这将是 采用原位杂交的方法进行研究。据推测，不同的 细胞色素P17基因表达水平反映蛋白质介导的性别差异 转录调控。CyP17启动子区域的DNA序列分析 通过筛选cDNA文库，进行5？种族，以及 斑马雀基因组文库的筛选。这代表着在 确定差异调控细胞色素P17转录的因子 发育中的雄性和雌性斑雀的端脑。他们还将 提示其他生物中雄激素合成的潜在调节机制 物种，包括人类。

DESCRIPTION (provided by applicant): The zebra finch song system consists of sexually dimorphic nuclei. Early estrogen treatment masculinizes telencephalic song nuclei in genetic females, but blocking estrogen does not demasculinize these nuclei in genetic males. Studies have suggested that the existence of a genetic factor intrinsic to the brain underlies the masculine pattern of song system organization. Recently, a sex difference has been seen in transcriptional levels of 17 alpha hydroxylase (CYP 17), the enzyme that makes androgen, in the telencephalon of developing zebra finches. It is hypothesized that GYP 17 expression extends through the steroid sensitive period of song system development, and is distributed near the song nuclei. This will be investigated using in situ hybridization. It is hypothesized that the different levels of CYP17 mRNA reflect sex differences in protein-mediated transcriptional regulation. DNA sequence from the promoter region of the CYP 17 gene will be determined by screening a cDNA library, performing 5? RACE, and screening a zebra finch genomic library. This represents a first step in identifying the factors that differentially regulate CYP 17 transcription in the telencephalon of developing male and female zebra finch. They will also indicate potential regulatory mechanisms for androgen synthesis in other species, including humans.