Subcellular localization of peptides, proteins, and RNA

Open Access
Russell, Jay Hunter
Graduate Program:
Biochemistry and Molecular Biology
Doctor of Philosophy
Document Type:
Date of Defense:
June 10, 2009
Committee Members:
  • Kenneth Charles Keiler, Dissertation Advisor
  • Kenneth Charles Keiler, Committee Chair
  • Sarah Ellen Ades, Committee Member
  • Melissa Rolls, Committee Member
  • Donald Bryant, Committee Member
  • Ahmed Heikal, Committee Member
  • protein localization
  • RNA localization
Recent bacterial imaging studies have revealed that the prokaryotic cell has more complex spatial organization than previously understood. Bacterial proteins, such as those involved in proteolysis and metabolic pathways, are localized to particular regions of the cell. Furthermore, the accurate localization of individual proteins and complexes is required for essential processes, including motility, chemotaxis, cell cycle progression, and cell division. Taken together, these observations raise the question of how many proteins are localized in a bacterium, which is the focus of Chapter 2. With the discovery of localized proteins, another question is how proteins are directed to the correct sub-cellular address. In accordance, the findings presented in Chapter 3 suggest that localization signals direct proteins to subcellular positions. Chapter 4 build upon our molecular localization studies by showing that, in addition to proteins, a small regulatory RNA, tmRNA, also localizes within a bacterial cell. While this thesis focuses on addressing these important questions, we also discuss the importance of these findings in terms of bacterial cell biology.