TRANSCRIPTION REGULATORS IN BONE

骨骼中的转录调节因子

• 批准号: 2131292
• 负责人: JOSEPH H ZERNIK
• 金额: $ 18.03万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-03-01 至 1996-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2131292
• 关键词: DNA binding protein; DNA footprinting; RNase protection assay; alkaline phosphatase; cell differentiation; cell growth regulation; complementary DNA; enzyme induction /repression; gel mobility shift assay; gene expression; genetic enhancer element; genetic library; genetic mapping; genetic promoter element; in situ hybridization; laboratory rat; limb bone; mandible /maxilla; messenger RNA; northern blottings; osteoblasts; osteocytes; osteogenesis; phenotype; polymerase chain reaction; procollagen; tissue /cell culture; transcription factor; western blottings

The current proposal addresses the role of transcription regulators in osteoblastic differentiation, and the correlation between differentiation and proliferation in osteoblastic cells in vivo. We will utilize two model systems for studying osteoblastic differentiation in vivo: the mandible, as a model system for craniofacial intramembranous osteogenesis, and the limb, as a model system for endochondral osteogenesis. In particular, we will study events related to the induction of alkaline phosphatase expression, which is a hallmark of osteoblastic differentiation in both endochondral and intramembranous osteogenesis. Evidence gathered in a variety of cell lineages suggests that both differentiation and proliferation are regulated by DNA binding transcription factors. In the proposed studies we will investigate the role of several recently isolated transcription factors, namely, Id and Twist (which are related to the MyoD gene family), as well as the CAAT Enhancer Binding Protein (C/EBP) in osteoblastic differentiation and proliferation. We will investigate the spatial and temporal distribution of these factors during bone development in the model systems mentioned above, and correlate expression of these factors with cell proliferation and alkaline phosphatase and typel procollagen expression. Furthermore, in an attempt to identify novel transcription regulators in bone, we will investigate and characterize nuclear proteins that specifically interact with the promoter region of the gene for bone alkaline phosphatase. We will also characterize changes in this binding activity during osteoblastic differentiation, and correlate these changes with induction of alkaline phosphatase expression and the regulation of cell proliferation. We will further isolate cDNA clones for such factors. Alternatively, attempts will be directed at isolating cDNA clones for new transcription factors from bone, based on their homology to known transcription regulators. These studies will improve our understanding of the maturation of the osteoblastic phenotype in vivo, and will allow better definition of the progression of the osteoblastic cell lineage at the molecular level.

当前的提案涉及转录调节器在 成骨细胞分化以及分化之间的相关性 和体内成骨细胞的增殖。 我们将使用两个 研究体内成骨细胞分化的模型系统： 下颌骨，作为颅内颅内的模型系统 成骨和肢体作为内侧软骨的模型系统 成骨。 特别是，我们将研究与 诱导碱性磷酸酶表达，这是 内膜和膜内的成骨细胞分化 成骨。 在各种细胞谱系中收集的证据表明 分化和增殖都受DNA结合调节 转录因子。 在拟议的研究中，我们将研究 最近隔离的转录因子的作用，即ID和 扭曲（与Myod基因家族有关）以及CAAT 成骨细胞分化和 增殖。 我们将研究空间和时间分布 在提到的模型系统中骨骼发育过程中的这些因素中 以上，并将这些因子的表达与细胞增殖相关联 和碱性磷酸酶和打字procollagen表达。 此外， 为了识别骨骼中新型的转录调节剂，我们将 研究并表征特异性相互作用的核蛋白 骨碱性磷酸酶的基因启动子区域。 我们 还将表征这种结合活动的变化 成骨细胞分化，并将这些变化与诱导相关 碱性磷酸酶表达和细胞调节 增殖。 我们将进一步隔离cDNA克隆的这些因素。 或者，尝试将尝试隔离为新的cDNA克隆 基于其同源到已知的骨骼的转录因子 转录调节器。 这些研究将提高我们的理解 体内成骨细胞表型的成熟，并将 可以更好地定义成骨细胞的进展 分子水平的谱系。