The Rockefeller University
Host: Guy Sella
Title: Host and bacteriophage determinants of CRIPSR-Cas9 adaptive immunity
Abstract: Bacterial CRISPR-Cas systems provide adaptive immunity against bacteriophages and plasmids by incorporating short, ~30bp DNA sequences from these cellular invaders into the CRISPR locus. These "spacer" sequences are transcribed into guide RNAs which direct CRISPR effectors to cleave matching targets during subsequent encounters with foreign agents. I study the CRISPR-Cas system from S. pyogenes, which encodes an effector cas9 that has emerged as a powerful genome-editing tool. I have asked fundamental questions underlying CRISPR immunity in vivo: How are foreign substrates identified during spacer acquisition? When are spacers acquired during the bacteriophage life-cycle? How do bacterial and phage genes influence CRISPR function? My future work will more broadly explore how CRISPR systems interact with their bacterial hosts and bacteriophage targets. These studies will synthesize basic immunological principles and mechanisms, the function and evolution of CRISPR systems and the development of Cas9-editing tools.