CRISPR-Cas : An Adaptive Immune System
Résumé
In genetics, clustered regularly interspaced short palindromic repeats, more commonly referred to as CRISPRs, are a family of repeated sequences of nucleotides widely distributed in archaeal and bacterial genomes. This chapter focuses on the fundamental aspects associated with research dedicated to CRISPR-Cas systems and discusses the diversity of CRISPR-Cas systems, their evolutionary dynamics, their role as an adaptive immune system, their impact on the co-evolution of microbes and their parasites, and their significance in nature. The development of algorithms allowing the automatic detection of CRISPRs and cas genes from genomic sequences and the analysis of all fully sequenced genomes has enabled the different characteristics of repeats, spacers and associated cas genes to be determined. A key step in understanding the function of CRISPRs was the identification of the origin of spacers, whose diversity is staggering.