MARC 主機 00000nam a2200541K 4500 001 AAI27726326 005 20201105110322.5 006 m o d 007 cr mn ---uuuuu 008 201105s2019 miu sbm 000 0 eng d 020 9781392878248 035 (MiAaPQ)AAI27726326 035 (MiAaPQ)0098vireo4626Bettridge 040 MiAaPQ|beng|cMiAaPQ|dNTU 100 1 Bettridge, Kelsey Elaine 245 10 Probing The Dynamics of RNA Polymerase and Hu in Live E. coli Cells 264 0 |c2019 300 1 online resource (185 pages) 336 text|btxt|2rdacontent 337 computer|bc|2rdamedia 338 online resource|bcr|2rdacarrier 500 Source: Dissertations Abstracts International, Volume: 81- 08, Section: B 500 Advisor: Wolberger, Cynthia 502 Thesis (Ph.D.)--The Johns Hopkins University, 2019 504 Includes bibliographical references 520 Diffusion is at the heart of every biochemical process. Millions of proteins must navigate the heterogeneous, crowded cellular milieu to perform their various tasks. This molecular crowding has a significant effect on the diffusive behavior and kinetic rates of proteins and biochemical reactions. A powerful technique to understand biochemical processes within the context of this heterogeneous environment is single particle tracking (SPT). In Chapter 2, I use SPT to elucidate the dynamics of the RNAP search process and transcription cycle in live E. coli cells. Using FRAP, I find that transcription follows a simple initiation-elongation-termination cycle with kinetic rates that closely match those in the literature. Using SPT, I probed the search process of RNAP and found three diffusive states corresponding to DNA- bound, diffusion within the dense nucleoid, and diffusion within the cytoplasm. RNAP exhibited confinement in each state and displayed a preference for a DNA-bound state, suggesting a grid search strategy. Additionally, RNAP displayed kinetics that were not consistent with steady state kinetics. In Chapter 3, I use SPT to probe the molecular mechanism of HU-mediated chromosome organization. Using genetic mutations that abolish the various binding modes of HU, I find that HUαα and HUαβ displayed differential dynamics. Additionally, HUαα seems primarily responsible for non-specific binding while HUαβ seems primarily responsible for repressor loop formation. The kinetics of HU were highly transient, indicative of their non-specific binding across the nucleoid, and suggested a mechanism by which cumulative forces of thousands of HU are able to achieve chromosomal organization, a marked departure from the long-lived binding of other DNA organization proteins such as histones 533 Electronic reproduction.|bAnn Arbor, Mich. :|cProQuest, |d2020 538 Mode of access: World Wide Web 650 4 Microbiology 650 4 Optics 650 4 Biophysics 653 Biophysics 653 Single particle tracking 653 Diffusion 653 Fluorescence microscopy 653 Gene regulation 653 Chromosome organization 653 Nucleoid organization 653 RNA polymerase 653 DNA-binding protein 655 7 Electronic books.|2local 690 0786 690 0410 690 0752 710 2 ProQuest Information and Learning Co 710 2 The Johns Hopkins University.|bProgram in Molecular Biophysics 773 0 |tDissertations Abstracts International|g81-08B 856 40 |uhttp://pqdd.sinica.edu.tw/twdaoapp/servlet/ advanced?query=27726326|zclick for full text (PQDT) 912 PQDT
館藏地 | 索書號 | 條碼 | 處理狀態 |
---|