Korean researchers have developed a new technology that allows real-time observation of the change process of the signal transduction switch protein involved in various cellular functions, such as cancer cell migration and neuronal activation.
A research team led by professor Huh Won-do (department of biological sciences, KAIST) at the Center for Cognition and Sociality of the Institute for Basic Science (IBS) announced on Jan. 14 that it developed a new biosensor to monitor the movement of signal transduction switch proteins. The team succeeded in observing nerve cell activation in live mice using this biosensor. The biosensor allows researchers to observe the cancer cell metastasis and the structural changes of nerve cells in the brain of live animals.
The team observed that small GTPase protein (protein that plays a key role in the cell signaling system) is activated by expressing a biosensor in cancer cells metastasized with breast cancer and controlling the direction of cancer cell movement by optogenetics technology. In this process, the team succeeded in imaging the movement and activation process of cellular small GTPase in real-time when the direction of movement of the cancer cells is changed. The team expects the technology to be applied to a variety of future researches, such as to detect the activity of small GTPases in real time to explore cancer-treatment materials.
"We have succeeded in overcoming the technical limitations of conventional biosensors for the observation of small GTPase proteins in vivo," said Prof. Huh, who led the study. "Since this technology can be used with the green light-using optogenetics technology, we expect it to be applied to a wide range of cell signal transduction and brain cognitive science studies related to various cell membrane receptors," he added.
In addition, the team conducted a joint research with Dr. Kwon Hyung-bae's lab at Max Planck Institute, Florida. The team was able to compare the activity of the small GTPase protein in motor cortex neurons of the anesthetized control group with that of the awake group running on a ball.
This is the first time that researchers observed the activity of small GTPase protein that changes in real time in a few nanometer units of dendritic spine in a live mouse.
This newly developed biosensor is sensitive enough to monitor the target protein even in the minute structure of several micrometers in size, such as a synapse. It is expected to be applied to various brain studies since it allows real-time observation of the brain in a natural state without interfering with the physiological activities, such as the exercise behavior of the mouse.
The findings of this study were published in global journal Nature Communications Online.