A team of scientists from the Universities of Würzburg, Birmingham and Wroclaw has succeeded in directly observing and investigating the initial contacts between individual receptors and G proteins and the following events taking place at the surface of living cells. The work was published yesterday in Nature.
"We were able to show that receptors and G proteins preferentially meet at special sites on the cell membrane, which we call hot spots," explains Professor Davide Calebiro, M.D., Ph.D., the senior author of the study.
These observations were made possible using a method based on single-molecule microscopy. They saw that the interaction between receptors and G proteins were quick and did not usually last longer than one second. In addition, they found that the cytoskeleton plays an impactful role in the formation of the hot spots. According to the researchers, these hot spots for receptor signaling were previously unknown.
Calebiro and the team believe that the hot spots play an important role on receptor signaling by increasing both the speed and efficiency of G protein activation. They also think that the hot spots allow the signals to stay local. According to the scientists, their new findings show that "apparently simple biological processes can be highly sophisticated once observed from a short distance." They anticipate that the current "exceptional advances" in imaging techniques will lead to a much deeper understanding of these processes in the near future.