It has recently been discovered that prokaryotes can acquire resistance to viruses and plasmids by integrating short fragments of foreign DNA into clusters of regularly interspaced short palindromic repeats (CRISPR's). These repeats are then transcribed and processed into small guide RNA's that are used to direct the destruction of foreign nucleic acid. This mechanism has many parallels with eukaryotic RNA interference but the proteins that are associated with the CRISPR response are evolutionarily unrelated to their eukaryotic counterparts. Our long-term goal is to understand the biochemical and structural basis of CRISPR-mediated resistance in prokaryotes. The objective here is to determine the mechanism by which an effector protein, responsible for the ultimate destruction of the foreign invader, is recruited specifically to foreign DNA. Our objective will combine biochemical, structural and cell based experiments. Successful completion of the proposed studies is significant because it will increase our understanding of bacterial resistance to viruses and plasmids. Both of these genetic elements play important roles in the genetics of pathogenic bacteria.

Public Health Relevance

The proposed research is relevant to public health because it will increase our understanding of how pathogenic bacteria protect themselves from invasion by mobile genetic elements, such as viruses and plasmids. This is important because invasion by these elements is a major route by which bacteria acquire antibiotic-resistance and greater virulence. Thus, the proposed research is relevant to the NIH's goals of improving the control of disease, enhancing human health and advancing our understanding of biological systems.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
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Macromolecular Structure and Function B Study Section (MSFB)
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Bender, Michael T
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Johns Hopkins University
Schools of Public Health
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