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The Expanding Class 2 CRISPR Toolbox: Diversity, Applicability, and Targeting Drawbacks

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Abstract

The class 2 clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system, one of the prokaryotic adaptive immune systems, has sparked a lot of attention for its use as a gene editing tool. Currently, type II, V, and VI effector modules of this class have been characterized and extensively tested for nucleic acid editing, imaging, and disease diagnostics. Due to the unique composition of their nuclease catalytic center, the effector modules substantially vary in their function and possible biotechnology applications. In this review, we discuss the structural and functional diversity in class 2 CRISPR effectors, and debate their suitability for nucleic acid targeting and their shortcomings as gene editing tools.

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Acknowledgements

We would like to acknowledge Lora Starrs and Alexander McKay for fruitful discussions and critical reading of the manuscript. Dr. Burgio’s research program is supported by the National Health and Medical Research Council of Australia (APP1143008), the Australian Research Council (DP180101494), and the National Collaborative Research Infrastructure Strategy (NCRIS) via the Australian Phenomics Network. Arash Hajizadeh Dastjerdi is supported by a JCSMR postgraduate scholarship, and Anthony Newman is supported by a Research Training Program domestic scholarship. We finally wish to acknowledge two anonymous reviewers and the editor for their helpful and excellent suggestions on the manuscript.

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  1. Department of Immunology and Infectious Diseases, The John Curtin School of Medical Research, The Australian National University, 131 Garran Road, Canberra, ACT, 2603, Australia

    Arash Hajizadeh Dastjerdi, Anthony Newman & Gaetan Burgio

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  1. Arash Hajizadeh Dastjerdi
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  2. Anthony Newman
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Correspondence to Gaetan Burgio.

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AHD, AN, and GB declare that they have no conflict of interest.

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Hajizadeh Dastjerdi, A., Newman, A. & Burgio, G. The Expanding Class 2 CRISPR Toolbox: Diversity, Applicability, and Targeting Drawbacks. BioDrugs 33, 503–513 (2019). https://doi.org/10.1007/s40259-019-00369-y

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