Scientists Innovatively Modified an Approach to Dissect Kinases
The top is a structural model of uniRapR domain which binds small molecule rapamycin. The bottom left depicts inactive state of the protein of interest modified with uniRapR domain. Binding of rapamycin and uniRapR reactivates the protein (bottom right).
The approach mentioned here is rapamycin regulated (RapR). It is a simple and reliable approach of protein engineering. Researchers once used it to show how Src kinase affects the way cell extends and moves. But this approach has a serious defect.
RapR relies on two proteins and the drug to control switch mechanism. The first protein was given the RapR modification and put in cells in tissue culture. The second protein was placed in the cells as well, but simply floated around until the addition of drug caused it to latch on to the modification in the first protein and turn it on. The issue lies in the uneven distribution of two proteins, for example, some cells could have lot of the first protein but fewer the second protein.
This defect could cause unstable result in studies. In order to solve the problem, researchers broke the two proteins into independent components and structures: alpha helices and beta sheets. And then they combined the two proteins into one. They named the new approach uni RapR.
Compared the two approaches with the same kinase, Src, which participates in the metastasis or spread of cancer cells, they gained more clear, reliable and consistent result. In past, scientists have assumed that Src involves in cell motility. Due to technique limit, they can’t isolate Src from other similar proteins. This time, in cultured human cells and in the model organism zebrafish, researchers found that switching on Src leads to cell extending its edges as part of cell movement.
With one confirmation, researchers believed this new approach can also be applied to investigate other kinases.
Article Link: Scientists Innovatively Modified an Approach to Dissect Kinases
Tags: Protein Engineering, uni RapR, Kinases, Src
