Hidden in plain sight: unveiling new components of CRISPR-Cas systems
Ville Hoikkala
University of St Andrews, Scotland
PrecisionPhage, Finland
CRISPR-Cas systems provide adaptive immunity for prokaryotes, protecting bacteria and archaea from viral (phage) infections. While traditionally understood as systems that directly cleave phage genomes, recent discoveries have revealed alternative mechanisms for CRISPR-Cas involving the generation of small signaling molecules synthesized upon infection and the subsequent activation of downstream effector proteins. These effector proteins induce growth-arrest, inhibiting phage replication and protecting the microbial communities from epidemics, while associated enzymes called ring nucleases can cleave the signaling molecules. Despite the identification of numerous effector and ring nuclease families in recent years, systematic analyses to characterize these systems remain limited. In this talk, I will present a bioinformatics-driven approach to characterize known systems and uncover previously unknown components of type III CRISPR-Cas systems using large public genomic databases, complemented by biochemical validation in the laboratory.
