Archive for March, 2017

Cellular Control – at the Flick of a Light Switch

What if you could turn on an enzyme inside a living cell—or release a cellular factor from its anchor—with the flick of a light switch?

Researchers at the University of Alberta’s Department of Chemistry have developed a new tool for manipulating biochemical processes within cells using light. By applying the unique properties of a photoconvertible fluorescent protein called mMaple, the team created such a light switch, a photocleavable protein called PhoCl (pronounced “focal”).

mMaple, whose name was inspired by the green-to-red color change of maple leaves as seasons transition, undergoes a light-dependent conformational change. Dr. Robert E. Campbell’s team engineered PhoCl to cleave into two pieces when exposed to light.

This novel optogenetic tool is especially useful for applications that involve manipulating cellular processes. For example, PhoCl can be used to create “caged” proteins that will not become activated until exposed to light. Researchers link one terminus of PhoCl to a cellular enzyme and the other terminus to an inhibitor, “caging” the enzyme and preventing it from performing its function. Upon exposure to violet light, PhoCl is cleaved to separate the inhibitor from the enzyme, thus activating the enzyme at the user’s command.

The cleavage mechanism of PhoCl is particularly useful for the activation of proteins within a specific location of a cell. Because intact PhoCl is fluorescent, researchers can visualize its location and movement within the cell and have control over when it cleaves. Upon cleavage, the fluorescence is quenched, enabling users to visually determine where the event took place.

As Allele Biotechnology & Pharmaceuticals is a licensed distributor of plasmids containing the gene for mMaple, the development of PhoCl is particularly exciting news to us and our customers. Interested readers can learn more about PhoCl in their paper published in Nature Methods.

Wednesday, March 22nd, 2017 Fluorescent proteins, Synthetic biology No Comments