Thursday, June 18, 2015

optogenetics meets crispr

thescientist |  The CRISPR gene-editing system just got even better: a new light-activated Cas9 nuclease could offer researchers greater spatial and temporal control over the RNA-guided nuclease activity, according to a study published today (June 15) in Nature Biotechnology.
“This is an effective new system for extremely precise control of gene editing via light,” Paul Knoepfler, a stem cell biologist at the University of California, Davis, who was not involved in the research, told The Scientist in an e-mail. “Any technological advancement that can add in the precision and control of genetic modification is an important advance,” he added, noting that “this is one of many such efforts.”
Recently, University of Tokyo chemist Moritoshi Sato and his colleagues developed pairs of photoswitching proteins called Magnets, which use electrostatic interactions to come together when activated by light. The team has also used photoactivatable technology to develop a light-activated CRISPR-based transcription system to target specific genes for expression. Now, Sato’s group has taken this one step further, using its Magnet proteins to create a photoactivatable Cas9 nuclease (paCas9) for light-controlled genome editing.
“The existing Cas9 does not allow to modify genome of a small subset of cells in tissue, such as neurons in the brain,” Sato told The Scientist in an e-mail. “Additionally, the existing Cas9 often suffers from off-target effects due to its uncontrollable nuclease activity. . . . We have been interested in the development of a powerful tool that enables spatial and temporal control of genome editing.”