April 22. A novel nuclease activated by low nucleotide levels

On Earth day, a study was published detailing the discovery of a novel sequence specific nuclease (GajA) in the bacterial defense against phages. Interestingly, nuclease activity of GajA is controlled by an ATPase-like domain and activation occurs when the nucleotide pool becomes depleted following replication and transcription by invading phages.

For more information, see Cheng, R., et al. (2021) A nucleotide-sensing endonuclease from the Gabijabacterial defense system. Nucleic Acids Research https://doi.org/10.1093/nar/gkab277

Keywords: CRISPR, Nuclease, Nucleotide Pool

April 20. Pre-clinical advances: CRISPR base editors to fix mutations Sickle Cell disease

In another tweak on the traditional CRISPR tool, Beam Therapeutics has recently unveiled a new CRISPR base editing tool specifically designed to directly edit the causative sickle hemoglobin point mutation.

For more information, see: Chu, S.H., et al. (2021) Editing of the Sickle Cell disease mutation. The CRISPR J.4: https://doi.org/10.1089/crispr.2020.0144

Keywords: CRISPR, base editing, Sickle Cell disease

March 16. New Tools: Comparison of prime editing versus templated gene editing in vivo

In a study published in Genome Biology, the authors compared prime editing and CRISPR-mediated homology-directed repair to create inactivating base pair changes. They found that prime editing eliminated indels and off target effects compared to CRISPR-mediated homology-directed repair.

For more information, see: Gao, P., et al. (2021) Prime editing in mice reveals the essentiality of a single base in driving tissue-specific gene expression. Genome Biol. 22: https://doi.org/10.1186/s13059-021-02304-3

Keywords: CRISPR, prime editing, homology directed repair

Questions? Email: crispr@amsterdamumc.nl