WINGED HELIX FACTORS IN EMBRYONIC DEVELOPMENT

先天性出生缺陷是新生儿的致病因素之一 发病率和死亡率。人类异质性综合征，如 Karagener综合征，通常伴有致命性心脏缺陷和 纤毛结构和功能缺陷。了解它们的起源 这些缺陷的存在需要阐明其潜在的机制。 胚胎的正常发育。有翼螺旋转录 因素通过调节在发展中发挥重要作用 细胞分化和细胞特异性基因表达。 肝细胞核因子/叉头同系物(HFH)-4是 有翼螺旋家族在发育过程中表达于各种 上皮组织。HfH-4基因突变的纯合子小鼠 有先天性左右轴不对称异常和 缺少纤毛。因此，HFH-4对于确定左-右是必不可少的 发育过程中轴不对称和纤毛细胞分化。 在拟议的研究中，我们将开始阐明 左右不对称性测定与纤毛上皮细胞 用HFH-4进行鉴别。开始了解基因 左右不对称的通路--早期胚胎模式 将确定HfH-4表达的类型，并确定其表达模式 其他左右基因将在HfH-4小鼠身上进行研究。这个 HfH-4小鼠纤毛上皮结构的研究 电子显微镜，以及测定的表达 纤毛细胞分化相关基因。差动 展示将被用来识别HfH-4的潜在靶基因。 人类HfH-4基因将被分离、鉴定和单一 链构象多态性分析在突变鉴定中的应用 在人类的HfH-4基因中。阐明细胞和分子 调节左右不对称性确定的机制有 对脊椎动物发育和脊椎动物病理学的重要意义 人类先天畸形。对差异化的洞察 纤毛细胞具有重要的意义 呼吸功能和病理以及生殖功能和 不孕不育。

Congenital birth defects are one of the lading causes of neonatal morbidity and mortality. Human heterotaxy syndromes, such as Kartagener syndrome, often have associated lethal cardiac defects and defects in ciliary structure and function. Understanding the origins of these defects requires an elucidation of the mechanisms underlying the normal development of the embryo. Winged helix transcription factors play important roles during development by regulating cellular differentiation and cell - specific gene expression. Hepatocyte nuclear factor/forkhead homologue (HFH) - 4 is a member of the winged helix family expressed during development in a variety of epithelial tissues. Mice homozygous for disruption of the hfh-4 gene have congenital abnormalities of the left-right axis asymmetry and lack cilia. HFH-4 is thus essential for determination of left-right axis asymmetry and ciliated cell differentiation during development. In the proposed studies, we will begin to elucidate the mechanisms of left-right asymmetry determination and ciliated epithelial cell differentiation by HFH-4. To begin to understand the genetic pathways involved in left-right asymmetry the early embryonic pattern of HFH-4 expression will be determined and the expression patterns of other ~left-right~ genes will be studied in hfh-4 mice. The structure of ciliated epithelium in hfh-4 mice will be studied by electron microscopy, as well as determination of the expression of genes associated with ciliated cell differentiation.. Differential display will be used to identify potential target genes for HFH-4. The human HFH-4 gene will be isolated and characterized and single chain conformation polymorphism analysis used to identify mutations in the human HFH-4 gene. Elucidating the cellular and molecular mechanisms regulating the determination of left-right asymmetry has great significance for vertebrate development and the pathology of human congenital malformations. Insights into the differentiation of ciliated cells have important implications for understanding the respiratory function and pathology and for reproductive function and infertility.