RADIATION SIGNALING THROUGH THE ALPHA6 BETA4 INTEGRIN

通过 ALPHA6 BETA4 整合素的辐射信号

• 批准号: 2896099
• 负责人: ANNE E CRESS
• 金额: $ 19.87万
• 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/2896099
• 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 粘附受体和信号受体对细胞内 细胞外环境 要检验的假设是， 辐射激活α 6 β 4整联蛋白。 整合素活化通过以下方式发生： 氧化外部色氨酸残基，并导致 在B 4亚基的胞质表面上的磷酸酪氨酸信号。 的 整联蛋白信号增加作为损伤反应的基因的反式激活。 具体目标是：1. 确定色氨酸氧化或 α 6 β 4整合素酪氨酸磷酸化状态的改变 是由电离辐射引起的 2. 确定是否停用 6 B4构建体将阻断辐射诱导的信号级联。 B 4 整联蛋白具有广泛的胞质结构域， 激活基序（TAM）。 具有细胞质的b4整合素的构建体 将测试删除的部分和/或删除的TAM的能力， 用电离辐射发出信号。 3. 确定是否激活 整联蛋白可以被过量的天然或合成的配体阻断， 整联蛋白 6 b 4的天然配体是层粘连蛋白5。 这将用于 测试信号是否可以被a 6 B 4的接合B衰减 整合素与其配体或受体的簇集。 可选择地， 与α 6 β 4整联蛋白相互作用的合成肽将作为 激动剂 4. 确定电离辐射是否激活了a 6 b 4 导致报告基因转录的诱导。 我们将使用 α 6 β 4整联蛋白的构建体和pGL 2-报告载体的用途 系统利用荧光素酶基因来测试依赖性， 对于B 4整联蛋白的信号传导部分的转录应答。 的 拟议的工作将增加我们目前对细胞信号传导的了解。 辐射损伤反应，基本整合素生物学和建议的方法， 从而增加6 B4的放射治疗的功效 表达上皮癌。