RADIATION SIGNALING THROUGH THE ALPHA6 BETA4 INTEGRIN

通过 ALPHA6 BETA4 整合素的辐射信号

• 批准号: 2606575
• 负责人: ANNE E CRESS
• 金额: $ 19.51万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-04-01 至 2001-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2606575
• 关键词: DNA damage; SDS polyacrylamide gel electrophoresis; autoradiography; biological signal transduction; confocal scanning microscopy; flow cytometry; genetic transcription; hydroxyl radical; immunoprecipitation; integrins; ionizing radiation; laminin; ligands; luciferin monooxygenase; oxidation; phosphorylation; reporter genes; synthetic peptide; tissue /cell culture; transfection

DESCRIPTION: Recent advances in cell biology have shown the integrins to be adhesive and signaling receptors responsive to alterations in the extracellula environment. The hypothesis to be tested is that ionizing radiation activates the a 6b 4 integrin. The integrin activation occurs by oxidation of the external tryptophan residues and results in a phosphotyrosine signal on the cytoplasmic face of the b 4 subunit. The integrin signal increases the transactivation of genes as a damage response. The specific aims are: 1. Determine if tryptophan oxidation or an alteration of the tyrosine phosphorylation state of the a 6b 4 integrin occurs in response to ionizing radiation. 2. Determine if inactivating a 6b 4 constructs will block the radiation induced signaling cascade. The b 4 integrin has an extensive cytoplasmic domain which contains the tyrosine activation motif (TAM). Constructs of theb 4 integrin with the cytoplasmic portion deleted and/or TAM deleted will be tested for their ability to signal with ionizing radiation. 3. Determine if the activation of the integrin can be blocked by excess of the natural or synthetic ligand of the integrin. The natural ligand for a 6b 4 is laminin 5. This will be used to test whether the signaling can be attenuated b engagement of the a 6b 4 integrin with its ligand or clustering of the receptor. Alternatively, synthetic peptides which interact with the a 6b 4 integrin will be tested as agonists. 4. Determine if the a 6b 4 activation by ionizing radiation results in the induction of transcription of a reporter gene. We will use the constructs of the a 6b 4 integrin and the use of a pGL2-reporter vector system utilizing the luciferase gene to test the dependence of the transcription response for the signaling portion of the b 4 integrin. The proposed work will add to our current knowledge of cellular signaling of a radiation damage response, basic integrin biology and suggested ways in which to increase the efficacy of the radiation treatment of a 6b 4 expressing epithelial cancers.

描述：细胞生物学的最新进展表明整合素是 粘附性受体和信号受体对细胞周期改变的反应 胞外环境。需要检验的假设是电离 辐射可激活a6b4整合素。整合素的激活通过以下途径发生 外部色氨酸残基的氧化并导致 B4亚基胞质面上的磷酸酪氨酸信号。这个 整合素信号作为一种损伤反应增加了基因的反式激活。 具体目标是：1.确定色氨酸氧化或一种 A6B4整合素酪氨酸磷酸化状态的改变 发生在对电离辐射的反应中。2.确定是否停用 6B4结构将阻断辐射诱导的信号级联反应。B4 整合素有一个广泛的细胞质结构域，其中含有酪氨酸 激活主题()。B4整合素与细胞质的构建 被删除的部分和/或被删除的将被测试他们的能力 带有电离辐射的信号。3.确定是否激活 整合素可以被过量的天然或合成配体所阻断 整合素。6b4的天然配体是层粘连蛋白5。这将用于 测试a-6b-4接续时信令是否可以衰减 整合素及其配体或受体的聚集物。或者， 与a6b4整合素相互作用的合成肽将被测试为 激动剂。4.确定a6b4是否通过电离辐射激活 结果诱导了报告基因的转录。我们将使用 A6b4整合素的构建及pGL2报告基因载体的应用 一种利用荧光素酶基因检测细胞依赖性的系统 B4整合素信号部分的转录反应。这个 拟议的工作将增加我们目前对细胞信号转导的了解 辐射损伤反应、整合素的基本生物学和建议的治疗方法 其中增加了6b4放射治疗的疗效。 表现为上皮癌。