REGULATION OF THE MURINE CALCITONIN RECEPTOR GENE

描述(摘自调查者摘要)：降钙素(CT) 最初被鉴定为一种内分泌荷尔蒙，它能降低 细胞外钙通过抑制破骨细胞性骨吸收和 促进肾钙排泄。沙眼衣原体CT受体的鉴定 不同的组织和细胞类型及其对组织和细胞的影响 发育中的胚胎表明CT可能服务于更复杂和多样化的 它在调节动态平衡方面的作用更大。这一发现表明 降钙素受体(CTR)基因交替剪接 CTR亚型可能结合CTL以外的配体提供了进一步的洞察力 这种功能多样性的分子和生物化学基础。在 拟议的研究，首席调查员将1)克隆和 鉴定小鼠CTR基因并鉴定其转录起点 破骨细胞和其他MCTR表达细胞类型中的S位点。2)定义 特定的和可能是唯一的调控序列负责 MCTR在细胞和组织中的表达及可能的鉴定 与这些序列结合的转录因子。品种繁多 将使用实验方法来定义控制因素 在发育过程中，MCTR在破骨细胞和其他类型细胞中的表达。 这将包括定义在监管中涉及的序列 降钙素(CT)和其他激素(例如， 地塞米松)或细胞因子(如IL-1)。据预计， 控制破骨细胞MCTR基因表达的调节因子也 参与调节其他基因的表达，这些基因 伴随着破骨细胞分化和激活的最后阶段。 3)研究MCTR基因的发育调控。世俗的 MCTR基因表达的特定细胞模式将被记录下来，以及 然后将转基因MCTR-LacZ报告小鼠用于分析 目标2中确定的监管区域的相关性，并定义任何 其他可能对发育正确很重要的序列 在体内表达。4)确定定向干扰的效果 MCTR基因在破骨细胞和其他MCTR表达组织中的表达，以及在小鼠身上的表达 发展。首席调查员和她的同事以及她 同事们将产生具有靶向干扰的转基因小鼠 MCTR基因。此外，他们还将发展ES细胞分化。 从E细胞中产生破骨细胞的技术研究 MCTR基因在破骨细胞分化和分化过程中的表达调控 发展。

DESCRIPTION (adapted from the Investigator's abstract): Calcitonin (CT) was originally identified as an endocrine hormone that lowers extracellular calcium by inhibiting osteoclastic bone resorption and enhancing renal calcium excretion. The identification of CT receptors in diverse tissues and cell types and the demonstration of its effects on the developing embryo indicates that CT may serve a more complex and diverse function than its role in regulating homeostasis. The discovery that the calcitonin receptor (CTR) gene is alternatively spliced and that certain CTR isoforms may bind ligands other than CTL provides further insight into the molecular and biochemical basis for this functional diversity. In the proposed studies, the Principal Investigators will 1) Clone and characterize the murine CTR gene and identify the transcription start site(s) in osteoclasts and other mCTR-expressing cell-types. 2) Define the specific and potentially unique regulatory sequences responsible for expression of mCTR expressing cells and tissues and identify the putative transacting transcription factors that bind to these sequences. A variety of experimental approaches will be used to define the factors controlling mCTR expression in osteoclasts and other cell types during development. This will include defining the sequences involved in the regulation of mCTR gene expression by calcitonin (CT) and other hormones (e.g., dexamethasone) or cytokines (e.g., IL-1). It is anticipated that the regulatory factors that control mCTR gene expression in osteoclasts also are involved in the regulation of the expression of other genes that accompany the final stages of osteoclast differentiation and activation. 3) Investigate the developmental regulation of the mCTR gene. The temporal and cell-specific pattern of mCTR gene expression will be documented, and then transgenic mCTR-lacZ reporter mice will be used to analyzed the relevance of the regulatory regions identified in Aim 2 and to define any other sequences that may be important for developmentally correct expression in vivo. 4) Determine the effect of targeted disruption of the mCTR gene on osteoclasts and other mCTR-expression tissues, and on mouse development. The Principal Investigator and her colleagues and her colleagues will generate transgenic mice with a targeted disruption of the mCTR gene. In addition, they will develop ES cell differentiation techniques to generate osteoclasts from E cells for studying the regulation of mCTR gene expression during osteoclast differentiation and development.