The Evolution and reprogramming of DNA replication fidelity

DNA不断地发生突变，了解这些突变是如何产生和修复的是细胞和生物体生存的关键一步。 控制DNA损伤的复制和修复酶存在于每种生物体中，但它们的效率在已知的生命中差异很大。 在该项目中，在自然条件下进化的高保真复制酶将被转移到其他具有低保真复制酶的生物体中。 此外，该项目将研究不同的复制保真度如何影响生物体的生存以及塑造基因组的结构。 通过重新编程复制保真度，该项目旨在降低细胞突变率，增加细胞寿命和细胞健康。 这项工作将由K-12，本科生和研究生进行，包括两年一次的遗传工程研讨会，这将增加科学参与，促进少数民族在STEM研究中的职业生涯。该项目的总体目标是研究和操纵驱动DNA复制保真度的酶1）使用天然存在的，在四脲草履虫中发现的极高保真DNA复制酶，2）使用液滴数字PCR来模拟适合度效应的分布，以努力研究选择如何操作以基于有害负荷来改进复制保真度，3）研究复制保真度如何影响具有多条染色体的α变形菌的时空突变率变化，4）通过NC-MSEN大学预科项目改善K-12学生的STEM教育，和5）促进少数民族和弱势本科生，研究生和博士后研究人员在干这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

DNA is constantly subjected to mutations, and understanding how these mutations arise and are repaired is a critical step in cell and organismal survival. The replication and repair enzymes that control DNA damage are found in every organism, but their efficiency vary greatly across known life. In this project, high-fidelity replication enzymes that have evolved under natural conditions will be transferred into other organisms with low-fidelity replication enzymes. Furthermore, the project will investigate how varying replication fidelity can influence the survival of an organism as well as shape the structure of the genome. By reprogramming replication fidelity, the project seeks to reduce cellular mutation rates and increase cellular longevity and cellular health. This work will be performed by K-12, undergraduate, and graduate students, and include bi-yearly genetic engineering workshops that will increase scientific participation and promote the careers of minorities in STEM research.The overall objective of this project is to study and manipulate the enzymes that drive DNA replication fidelity by 1) reprogramming yeast DNA replication using naturally existing, extremely high-fidelity DNA replication enzymes found in Paramecium tetraurelia, 2) use droplet-digital PCR to model the distribution of fitness effects in an effort to investigate how selection operates to refine replication fidelity based on deleterious load, 3) investigate how replication fidelity influences spatiotemporal mutation-rate variation in alphaproteobacteria with multiple chromosomes, 4) improve STEM education for K-12 students through the NC-MSEN pre-college program, and 5) promote minority and disadvantaged undergraduate, graduate, and postdoctoral researchers in STEMThis award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.