Transcription Coupled DNA Repair and Human Disease

描述：(申请人提供)本项目与 癌症的分子流行病学。许多独立的遗传事件发生在 从正常细胞向恶性细胞转化。基因组DNA发生变化 并可导致原癌基因的激活或失活 通过突变、重组、基因扩增， 易位或其他染色体异常。在某种人类遗传中 疾病，肿瘤发生率的增加与 修复和/或复制受损的DNA。我们的最终目标是 了解哺乳动物细胞中受损DNA的处理如何与 致癌。我们对人类细胞如何处理DNA特别感兴趣 全球基因组切除修复(GGR)途径中的损伤 转录偶联修复(TCR)。虽然GGR的缺陷是众所周知的 易患癌症，易患癌症，TCR的缺陷，如遗传性疾病Cockayne 综合征(CS)，不会。发育和神经学特征 CS的问题被认为是内源性TCR缺陷的结果 氧化DNA损伤。我们已经记录了“紫外线敏感”中的TCR缺陷 综合征“(UVSS)是一种遗传性疾病，不存在 CS的发育/神经学特征。我们建议检验一下我们的假设 UVSS基因产物通过核苷酸切除对TCR是必不可少的 修复途径，而不是通过碱基切除修复途径 氧化DNA损伤。UVSS可能是DNA修复过程中的关键基因 和抄写。 我们的建议包括以下子项目： (1)TCR在氧化DNA损伤修复中的作用将在UVSS中进行评估 细胞，使用既定的基因特异性修复方法。 (2)修复其他类别的DNA损伤(例如，苯并[a]芘二醇-环氧化物) 将使用单抗、32P后标记和基因 特异性修复试验，以进一步表征UVSS的修复缺陷 细胞。 (3)将在紫外线照射的UVSS细胞中进行诱变研究 与CS组比较。 (4)GGR活性基因和非活性基因的抑制现象 缺乏TCR的细胞将被进一步鉴定。 (5)将使用互补试验来鉴定来自 未知基因的光敏患者，从现有的 集合，用于分配给UVSS、CS或其他已知或未知综合征。 这一结果应该会增强我们对TCR在以下方面的作用的理解 人类肿瘤的发生和发展。TCR中涉及的新基因可能是 被发现了。新的互动可能会被揭示出来，这将澄清关系 在细胞DNA交易之间。

DESCRIPTION: (PROVIDED BY APPLICANT) This project is concerned with the molecular epidemiology of cancer. Many independent genetic events occur in the transformation from a normal cell to malignancy. Changes in genomic DNA occur at specific sites and can lead to activation of proto-oncogenes or inactivation of tumor suppressor genes through mutation, recombination, gene amplification, translocation, or other chromosomal abnormalities. In some human hereditary diseases, an increased incidence of neoplasia is correlated with a defect in the repair and/or replication of damaged DNA. Our ultimate objective is to understand how the processing of damaged DNA in mammalian cells relates to carcinogenesis. We are particularly interested in how human cells process DNA lesions through the respective pathways of global genomic excision repair (GGR) and transcription-coupled repair (TCR). While a deficiency in GGR is well-known to predispose to cancer, a defect in TCR, as in the hereditary disease Cockayne syndrome (CS), does not. The characteristic developmental and neurological problems in CS are thought to be a consequence of defective TCR of endogenous oxidative DNA damage. We have documented a TCR deficiency in "UV Sensitive syndrome" (UVSS), a hereditary disease that does not present the developmental/neurological features of CS. We propose to test our hypothesis that the UVSS gene product is essential for TCR through the nucleotide excision repair pathway but not through the base excision repair pathway that deals with oxidative DNA lesions. UVSS could be a key gene in the link between DNA repair and transcription. Our proposal includes the following sub-projects: (1) The role of TCR in repair of oxidative DNA lesions will be assessed in UVSS cells, using established methods for gene-specific repair. (2) Repair of other classes of DNA damage (e.g., Benzo[a]pyrene diol-epoxide) will be assessed, using monoclonal antibodies, 32P post-labeling, and gene specific repair assays, to further characterize the repair deficiency in UVSS cells. (3) Mutagenesis studies will be performed in UV-irradiated UVSS cells for comparison with those in CS. (4) The phenomenon of inhibited GGR in active or inactive genes in TCR-deficient cells will be further characterized. (5) A complementation assay will be used to characterize cells from photosensitive patients of unknown genotype, obtained from existing collections, for assignment to UVSS, CS, or other known or unknown syndromes. The results should enhance our understanding of the role of TCR in relation to human tumorigenesis and development. New genes implicated in TCR may be discovered. Novel interactions may be revealed that will clarify relationships between cellular DNA transactions.