Structure and function of a prokaryotic argonaute from Pseudomonas aeruginosa

Abstract

Argonautes (Ago) are structurally and functionally diverse proteins present in all domains of life. A common feature of these ancient proteins is their ability to bind nucleic acid guides that target the protein to complementary sequences. Although eukaryotic argonautes (eAgo) have been well-studied, we still know very little about the function of prokaryotic argonautes (pAgo) in bacterial and archaeal species. To address this gap in our knowledge, my thesis focused on determining the biochemical properties as well as the cellular functions of a pAgo from the organism Pseudomonas aeruginosa PACS2 (PaAgo). Here, we show that PaAgo plays a role in regulating the expression of transposons within PACS2. I also present results indicating that deletion of the PaAgo gene and its neighboring genes causes toxicity to P. aeruginosa. Finally, I provide evidence that PaAgo and a neighboring protein are binding partners and form a multi-protein complex. Future work will focus on copurifying and sequencing PaAgo nucleic acid guides as well as clarifying the mechanisms guide acquisition and biological function.