Have you ever watched a spy move and felt yourself craving spy gadgets, such as explosive chewing gum, or a tricked out Aston Martin? Well if you are a genome-engineering scientist you can now get your very own spy gadget – self-destructing DNA! But this cool creation isn’t just to fulfill your 007 dreams, it solves two very real issues: environmental spillover of foreign genetic material and protection of intellectual property. Minimizing spillover is important to help prevent unintended effects of targeted genome editors on surrounding cells. Sadly, traditional DNA removal techniques are quite tedious, time consuming, and expensive to construct.
Brian Caliando and Christopher Voigt of MIT decided to tackle this issue by employing the famed CRISPR system to streamline the process of DNA removal, minimize side effects, and protect trade secrets. To ensure that targeted genome editors stick to their game plan, they devised a tool that degrades DNA in the host genome under pre-programmed conditions or in a timed inducible fashion. The duo’s genetically encoded device, named DNAi, is based on type-IE CRISPR functionality with modular CRISPR arrays consisting of 29-bp repeats that define its DNA targets.
Here is how DNAi enforces the rules:
- Given an input, DNAi degrades plasmid DNA by 108 –fold
- Targeting the whole genome with DNAi causes cell death, reducing viable cells by a factor of 108.
- The CRISPR component of DNAi is capable of directing degradation to specific genomic regions and could be used to complicate recovery and sequencing to protect intellectual property while minimizing environmental spillover to surrounding cells.
- DNAi can be successfully undertaken in an engineered organism without any side effects or impact on DNAi inducibility even after 2 months of passaging.
The authors acclaimed that “the DNAi device is compatible with other systems for the containment of genetically modified organisms, including devices that implement programmed cell death, DNA deletion and the re-coding of the genome to require non-natural amino acids”.
To learn how you can create your very own self-destructing DNA, sneak on over to Nature Communications, May 2015.