Evolution of Type IV CRISPR-Cas Systems: Insights from CRISPR Loci in Integrative Conjugative Elements of Acidithiobacillia.

ABSTRACT: Type IV CRISPR-Cas are a distinct variety of highly derived CRISPR-Cas systems that appear to have evolved from type III systems through the loss of the target-cleaving nuclease and partial deterioration of the large subunit of the effector complex. All known type IV CRISPR-Cas systems are encoded on plasmids, integrative and conjugative elements (ICEs), or prophages, and are thought to contribute to competition between these elements, although the mechanistic details of their function remain unknown. There is a clear parallel between the compositions and likely origin of type IV and type I systems recruited by Tn7-like transposons and mediating RNA-guided transposition. We investigated the diversity and evolutionary relationships of type IV systems, with a focus on those in Acidithioba

SUBMITTER: Moya-Beltran A 

PROVIDER: S-EPMC8658065 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature