Many of you may have heard about CRISPR/Cas9. Cas9 endonuclease, or enzyme, can act as “molecular scissors” to cut DNA at a location specified by a guide RNA. CRISPR Cas9 has revolutionized biomedical research and can be used as specific, efficient and versatile gene-editing technology we can harness to modify, delete or correct precise regions of our DNA .
Microbes have long been engaged in an arms race for dominance, and they have molecular weapons and defense mechanisms. This is where the CRISPR-Cas9 gene editing system originated; bacteria can chop up the DNA of invading viruses, and store bits of that DNA in their genome, which acts as a kind of memory of the viral infection. This process was harnessed for use in genetic engineering. But Cas9 is far from the only enzyme that bacteria can use against other microbes. Other enzymes that can cut DNA or RNA, nucleases, have been discovered in microbes.
The scientists at USU (Utah State University) has discovered another tool the CRISPR Cas12a2. Unlike CRISPR systems that target DNA (e.g., Cas9), this system (Cas12a2) targets RNA. Instead of making a single specific cut in the targeted DNA, like Cas9, when Cas12a2 binds RNA, it drastically changes its shape in a way that allows it to bind and cut any sequence of DNA or RNA. This cutting activity destroys the virus genome but also degrades the genome of the host cell, shutting down the cell before the virus can replicate.
Cas12a2 recognizes virus RNA and then kills or shuts down the infected cell before more viruses can be made. Although much more needs to be done, we can envision repurposing Cas12a2 to recognize infected human cells and then causing them to die before they can make new viruses. Effectively stopping an infection in its tracks. This could pave the way to such therapies that could extend to any cells with a specific genetic marker that could be recognized by Cas12a2, for example, cancer.
Microbes have long been engaged in an arms race for dominance, and they have molecular weapons and defense mechanisms. This is where the CRISPR-Cas9 gene editing system originated; bacteria can chop up the DNA of invading viruses, and store bits of that DNA in their genome, which acts as a kind of memory of the viral infection. This process was harnessed for use in genetic engineering. But Cas9 is far from the only enzyme that bacteria can use against other microbes. Other enzymes that can cut DNA or RNA, nucleases, have been discovered in microbes.
The scientists at USU (Utah State University) has discovered another tool the CRISPR Cas12a2. Unlike CRISPR systems that target DNA (e.g., Cas9), this system (Cas12a2) targets RNA. Instead of making a single specific cut in the targeted DNA, like Cas9, when Cas12a2 binds RNA, it drastically changes its shape in a way that allows it to bind and cut any sequence of DNA or RNA. This cutting activity destroys the virus genome but also degrades the genome of the host cell, shutting down the cell before the virus can replicate.
Cas12a2 recognizes virus RNA and then kills or shuts down the infected cell before more viruses can be made. Although much more needs to be done, we can envision repurposing Cas12a2 to recognize infected human cells and then causing them to die before they can make new viruses. Effectively stopping an infection in its tracks. This could pave the way to such therapies that could extend to any cells with a specific genetic marker that could be recognized by Cas12a2, for example, cancer.
