Loading...
Thumbnail Image
Publication

CRISPR-Cas Systems and the Paradox of Self-Targeting Spacers.

Wimmer, Franziska
Beisel, Chase L
Citations
Altmetric:
Advisors
Editors
Other Contributors
Issue Date
2019-01-01
Submitted date
Other Titles
Abstract
CRISPR-Cas immune systems in bacteria and archaea record prior infections as spacers within each system's CRISPR arrays. Spacers are normally derived from invasive genetic material and direct the immune system to complementary targets as part of future infections. However, not all spacers appear to be derived from foreign genetic material and instead can originate from the host genome. Their presence poses a paradox, as self-targeting spacers would be expected to induce an autoimmune response and cell death. In this review, we discuss the known frequency of self-targeting spacers in natural CRISPR-Cas systems, how these spacers can be incorporated into CRISPR arrays, and how the host can evade lethal attack. We also discuss how self-targeting spacers can become the basis for alternative functions performed by CRISPR-Cas systems that extend beyond adaptive immunity. Overall, the acquisition of genome-targeting spacers poses a substantial risk but can aid in the host's evolution and potentially lead to or support new functionalities.
Citation
Front Microbiol. 2020 Jan 22;10:3078. doi: 10.3389/fmicb.2019.03078. eCollection 2019.
Publisher
PubMed ID
PubMed Central ID
Additional Links
Embedded video
Type
Article
Language
Description
Series/Report no.
ISSN
1664-302X
EISSN
ISBN
ISMN
Gov't Doc #
Sponsors
License
Attribution-NonCommercial-ShareAlike 4.0 International