A new genome editing tool—minimal versatile genetic perturbation technology (mvGPT)—can achieve simultaneous and orthogonal gene editing and gene regulation in human cells. The coming together of these two goals into a single tool—that can independently address different genetic diseases in the same cell—opens new doors to treating genetic diseases and investigating the fundamental mechanisms of how our DNA functions.
This work is published in Nature Communications in the paper, “Orthogonal and multiplexable genetic perturbations with an engineered prime editor and a diverse RNA array.”
“Not all genetic diseases are solely caused by errors in the genetic code itself,” said Sherry Gao, PhD, associate professor in chemical and biomolecular engineering (CBE) and in bioengineering (BE) at the University of Pennsylvania. “In some cases, diseases with genetic components—like type I diabetes—are due to how much or little certain genes are expressed.”
The platform works by combining an improved Prime Editor, capable of modifying DNA sequences, with previously invented technologies for increasing and decreasing the expression of genes.
More specifically, the mvGPT combines “an engineered compact prime editor, a fusion activator MS2–p65–HSF1 (MPH), and a drive-and-process multiplex array that produces RNAs tailored to different types of genetic perturbation.”
“All these functions are orthogonal,” said Tyler Daniel, a doctoral student in the Gao Lab. “They can happen independently of each other at the same time.”
Further, mvGPT can “precisely edit human genome via Prime Editor coupled with a prime editing guide RNA and a nicking guide RNA, activate endogenous gene expression using Prime Editor with a truncated single guide RNA containing MPH-recruiting MS2 aptamers, and silence endogenous gene expression via RNA interference with a short-hairpin RNA.”
The team tested mvGPT on human liver cells by simultaneously correcting a c.3207C>A mutation in the ATP7B gene linked to Wilson’s disease, upregulating the PDX1 gene expression to potentially treat type I diabetes, and suppressing the TTR gene to manage transthyretin amyloidosis.
In multiple tests, mvGPT achieved all three tasks with high precision, demonstrating its ability to target multiple genetic conditions simultaneously.
Because mvGPT takes up less space than three separate tools, the system is also easier to transport into cells. The researchers showed that mvGPT can be delivered by multiple means, including strands of mRNA and viruses used to deliver genetic editing tools.
“When you have a single tool that can accomplish all of these things at the same time,” said Gao, “you make the process so much simpler because there’s less machinery you have to deliver to the cell.”
Now that the technology has shown promise in human cells, the researchers plan to test mvGPT in animal models, and against other diseases with genetic components, including cardiovascular diseases. “The more advanced our tools become,” continued Gao, “the more we can do to treat genetic diseases.”
