Spatiotemporal protein controller “LARIAT”
Researchers have developed the versatile technology to inactivate proteins in living cells using light, named Light-Activated Reversible Inactivation by Assembled Trap (LARIAT).
A precise inhibition of target proteins can serve as an effective means to dissect complex signaling networks or to identify new therapeutic targets. Although widely used, genetic alteration strategies cannot be applied to all proteins because the some proteins are very critical to an organism’s development; the absence of a necessary gene in early development can result in death. To address these drawbacks, small-molecule drugs have been developed, but do not allow researchers to study protein functions in specific regions and are poorly reversible.
The research group, led by Professor Won Do Heo in the Department of Biological Sciences developed a new technology, named Light-Activated Reversible Inhibition by Assembled Trap (LARIAT), that overcomes these challenges.
The LARIAT system acts to sequester target proteins from their active region inside cell, by using blue-light. This system consists of a blue-light-mediated protein-protein interaction and multimeric protein (MP). The light-sensitive protein cryptochrome 2 (CRY2) forms clusters with the protein CIB1 linked to multimeric proteins in the presence of blue light. These clusters would serve as synthetic intracellular compartments to conditionally trap, and thereby inactivate, target proteins fused to CRY2 upon blue-light illumination. This method provides researchers with a reversible and tunable way to control protein functions.
In addition, by linking CRY2 with single-domain antibody against the green fluorescent protein (GFP), LARIAT expands their application to control the function of any protein tagged with GFP.
Utilizing this system, researchers were able to effectively and reversibly inactivate diverse biological processes, including cell morphology, cell migration and cell division with high spatiotemporal resolution. This new technology can provide an unprecedented opportunity for investigating diverse protein functions in the dynamics of intracellular environment.
The research team published a paper according to LARIAT system on June in Nature Methods.