Ajuba, a novel regulator of the ATR response in human cells.

Ajuba，人体细胞 ATR 反应的新型调节剂。

• 批准号: 10208905
• 负责人: Diego Loayza
• 金额: $ 11.7万
• 依托单位: HUNTER COLLEGE
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-12 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10208905
• 关键词: Address; Apoptotic; Binding; Biological Assay; Cell Cycle; Cell Death; Cell Fractionation; Cell Survival; Cells; Chromatin; Complex; DNA Binding; DNA Damage; DNA Repair; DNA biosynthesis; Defect; Deletion Mutation; Development; Event; Exhibits; Family; Fanconi' s Anemia; Genomic Instability; Human; Immunofluorescence Microscopy; In Vitro; Knowledge; LIM Domain; Lead; Link; Malignant Neoplasms; Mammals; Mediating; Molecular; Nuclear; Oligonucleotides; Oligosaccharides; Pathway interactions; Phenotype; Phosphotransferases; Prevention; Proteins; Publications; Regulation; Repression; Role; S Phase; Single-Stranded DNA; Site; System; Testing; Therapeutic; Work; ZYX gene; base; cancer cell; experimental study; genome integrity; improved; insight; metaplastic cell transformation; novel; prevent; repaired; replication stress; response; small hairpin RNA; tumor; tumorigenesis

The ATR-dependent DNA damage response (DDR) is essential for genome integrity and constitutes an important tumor suppressive system. DNA replication stress has been linked to cellular transformation, and represents some of the early events leading to tumorigenesis in mammals. Our work has centered on proteins that are part of the `Zyxin' LIM family, characterized by the presence of tandem LIM domains at their C terminus, which we found were important for the repression of the DNA damage response in human cells. Specifically, we have discovered that Ajuba is essential for efficient repression of the ATR pathway in unperturbed cells. Depletion of Ajuba leads to activation of ATR, followed by a potent apoptotic response. We have discovered that Ajuba associates with the RPA complex, itself central to the ATR activation pathway, and have detected a direct interaction in vitro between Ajuba and the RPA70 subunit. RPA70 is composed of OB oligonucleotide/oligosaccharide-binding (OB) folds essential for single strand DNA binding and assembly of the ATR activation complex. Based on these observations, we hypothesize that Ajuba is an important repressor of inappropriate ATR activation in S phase through a direct interaction with RPA70. We are proposing to study in detail the direct contacts between Ajuba and RPA, and to analyze the significance of this interaction in human cells. Our results are expected to improve our understanding of the regulation of the DNA damage response in human cells, itself implicated in early events in cellular transformation and cancer.

ATR依赖的DNA损伤反应（DDR）对于基因组的完整性是必不可少的，并构成了 一个重要的肿瘤抑制系统DNA复制应激与细胞 转化，并代表了一些导致哺乳动物肿瘤发生的早期事件。我们 工作集中在作为“Zyxin”LIM家族的一部分的蛋白质上，其特征在于存在 在它们的C末端有串联的LIM结构域，我们发现这对抑制LIM结构域的表达是重要的。 人类细胞中的DNA损伤反应。具体来说，我们发现，阿朱巴是必不可少的， 在未受干扰的细胞中有效抑制ATR途径。阿朱巴的消耗导致激活 ATR，随后是有效的凋亡反应。 我们已经发现，阿朱巴协会与RPA复杂，本身中央ATR激活 途径，并已检测到在体外筋骨草和RPA 70亚基之间的直接相互作用。 RPA 70由OB寡核苷酸/寡糖结合（OB）折叠组成，所述OB寡核苷酸/寡糖结合折叠对于单个 链DNA结合和ATR活化复合物的组装。根据这些观察，我们 假设筋骨草是S期不适当ATR激活的重要阻遏物， 与RPA 70直接交互。我们建议详细研究阿朱巴与 和RPA，并分析这种相互作用在人类细胞中的意义。我们的结果是预期的 为了提高我们对人类细胞中DNA损伤反应调节的理解， 与细胞转化和癌症的早期事件有关。