Regulation of an Error-Prone Polymerase

易错聚合酶的调节

• 批准号: 6622874
• 负责人: PATRICIA LORRAINE FOSTER
• 金额: $ 21.1万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-04-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6622874
• 关键词: DNA directed DNA polymerase; DNA replication; Escherichia coli; bacterial genetics; enzyme activity; gene expression; gene mutation; genetic library; genetic manipulation; genetic regulation; genetic regulatory element; genetic screening; genetic transcription; genetic translation; immunoprecipitation; neoplasm /cancer genetics; phenotype; posttranslational modifications; protein purification; protein structure function; regulatory gene; yeast two hybrid system

Genomic stability is vital to the health of the individual and the preservation of the species. This stability can be threatened by DNA damage from endogenous and exogenous sources. However, mutations, which are heritable sequence changes in the DNA, can also arise as a result of errors made during replication of undamaged DNA. Recently an entirely new family of error-prone DNA polymerases has been discovered. Found in all three domains of life, these polymerases are beneficial because they can replicate past DNA lesions, but they are also potentially detrimental because they make frequent errors, even on undamaged DNA. If the activities of these polymerases are not controlled, they could be a potent source of the mutations that lead to genetic disorders such as cancer. The hypothesis underlying the proposed research is that cells can and must control the activities of their error-prone DNA polymerases. To test this hypothesis, pathways that control the activity of E. colts error-prone DNA polymerase IV (Pol IV) will be found and characterized. The specific aims are: (1) to identify new regulatory factors that affect the mutagenic activity of Pol IV; (2) to characterize the proteins and pathways regulating Pol IV levels or activity; and, (3) to further characterize the regulatory factors that are already identified. Because Pol IV is a close homologue of eukaryotic error-prone DNA polymerases, higher organisms, including humans, may use similar control mechanisms.

基因组的稳定性对个体的健康和物种的保存至关重要。这种稳定性可能受到来自内源性和外源性来源的DNA损伤的威胁。然而，突变是DNA中可遗传的序列变化，也可能是由于未受损DNA复制过程中的错误而引起的。最近发现了一个全新的易错DNA聚合酶家族。这些聚合酶存在于生命的所有三个领域，它们是有益的，因为它们可以复制过去的DNA损伤，但它们也是潜在的有害的，因为它们经常出错，即使是在未受损的DNA上。如果这些聚合酶的活性不受控制，它们可能是导致遗传疾病（如癌症）的突变的潜在来源。这项研究的基本假设是，细胞可以而且必须控制它们的易错DNA聚合酶的活动。为了验证这一假设，控制E.将发现并表征Colts易错DNA聚合酶IV（Pol IV）。具体目标是：（1）鉴定影响Pol IV致突变活性的新调节因子;（2）表征调节Pol IV水平或活性的蛋白质和途径;（3）进一步表征已鉴定的调节因子。由于Pol IV是真核生物易错DNA聚合酶的密切同源物，因此包括人类在内的高等生物可能使用类似的控制机制。