CRISPR enzymes show promise for disease diagnostics

Researchers at the University of California at Berkeley (UC Berkeley) recently described 10 clustered regularly interspaced short palindromic repeats (CRISPR) enzymes that have “Pac-Man-like” behaviors that chew up RNA, which could be used to detect infectious viruses.

Each enzyme is a variant of the Cas13a CRISPR protein and showed that, once it binds to its target RNA, the enzyme begins to indiscriminately cut up all RNA linked to a reporter molecule, making it fluorescent to allow signal detection.

A pair of Broad Institute research teams then paired the enzymes with RNA amplification, a process they called SHERLOCK, which showed that it could detect viral RNA amplification at extremely low concentrations, detecting the presence of Zika and dengue viral RNA. The teams said the system could be used to detect any type of RNA, even RNA associated with cancer cells.

“We have taken our foundational research a step further in finding other homologs of the Cas13a family that have different nucleotide preferences, enabling concurrent detection of different reporters with, say, a red and a green fluorescent signal, allowing a multiplexed enzymatic detection system,” UC Berkeley graduate student Alexandra East-Seletsky said.

Findings from the research appeared in the May 4 issue of the journal Molecular Cell.