Date of Graduation

Summer 2016


Master of Science in Cell and Molecular Biology


Biomedical Sciences

Committee Chair

Joshua Smith


The Snf2/Swi2 ATPases Rad5 and Rad16 have been shown to play vital roles in a number of DNA repair pathways. In both Saccharomyces cerevisiae and human cell lines, Rad5 homologs (SHPRH, HLTF) have been shown to function in DNA double strand break (DSB) repair along with pathways that repair damage after replication. The function of Rad16, unlike Rad5, has been found only in lower eukaryotes such as Saccharomyces, despite the fact that it plays an essential role in nucleotide excision repair (NER), and more specifically in the repair of silenced areas of the genome. In order to more fully understand the function of Rad16, this work focuses on using a model organism, Tetrahymena thermophila, to identify and characterize the functional aspects of both Rad5 and Rad16. To do this, qPCR analyses of the potential Rad5/16 homologs were conducted to determine their expression, while shRNA constructs were designed to inhibit their expression to assess the phenotypic consequences of DNA damage in deficient cells. Expression analyses showed that three of the potential homologs (Rad16, Rad5.2, and Rad5.1) have damage-depended expression, and that the levels of one can have substantial effects on levels of the others. Moreover, two of the homologs, Rad16NH and Rad5.1, show altered survival after genotoxic stress. The data showed that the functions of Rad16 and Rad5 homologs in Tetrahymena may diverge greatly from those in lower eukaryotes.


ad16, rad5, nucleotide excision repair, genome stability, snf2/swi2 atpase

Subject Categories

Medical Molecular Biology


© Andrew Francis Morin

Open Access