Scaffold Builders under a Microscope
New collaborative research center at Freie Universität studies protein structures at the cell membrane
Jan 31, 2012
It’s like on any well-organized construction site: Wherever things have to get done, the first step is to set up scaffolding. Larger construction projects need complex scaffolds that stand for a longer time, while smaller ones are equipped with simple, easily dismantled structures. The process is basically the same on and in cells, but instead of steel supports and pipes, it is proteins that build the scaffolding at the cell membrane. They help, for example, to constrict tiny bubbles in the membrane that then either release their contents outward or move into the interior of the cell. This is how the cell communicates with others via messenger substances, such as in the case of nerve cells.
Some cells, such as immune cells, can also use the same method to emit toxins to fight invasive substances. These kinds of structures are also needed to meld muscle precursor cells into muscle cells – definitely a larger construction site at the cellular level. And finally, hormones are also released using the very same mechanism.
“These protein scaffolds perform tremendously important functions, but they are still poorly understood,” says Volker Haucke, a professor of membrane biochemistry and molecular cell biology at Freie Universität. With this in mind, Haucke teamed up with colleagues to submit an application to the German Research Foundation (DFG), recently approved, for funding for a collaborative research center to unlock the mystery behind these scaffolds on an interdisciplinary basis. The team includes chemists, biochemists, biologists, mathematicians, physicists, and medical researchers, primarily from Freie Universität and Charité, the joint medical school operated by Freie Universität and Humboldt-Universität. Researchers from the Max Delbrück Center for Molecular Medicine (MDC) and the German Institute of Human Nutrition, in Potsdam, are also involved. The DFG recommended funding for the application without any restrictions.
Haucke and his colleagues will now receive about two million euros per year for their research for an initial period of four years, with the possibility of an extension for up to twelve years. The difficulties involved in studying the scaffolds are primarily of a technical nature. The scaffold structures are only about 100 nanometers in size – and a nanometer is just one-billionth of a meter. Using the microscopes available to date, researchers run into a dilemma. There are microscopes that can show individual molecules and microscopes that scientists can use to observe a process taking place between molecules in real time – but none that can do both. Building this kind of equipment from commercial components is part of the collaborative research center’s work.
Observing the processes as they take place is crucial for understanding them. Some scaffolds, such as those in the nerve cells, can be built up or dismantled in the span of milliseconds. In the case of muscle precursor cells, by contrast, building a scaffold takes anywhere from several minutes to an hour. With this in mind, the researchers plan to use part of their first funding installment to order a microscope that offers a good compromise between speed and resolution. There is only one such device in Germany at this time.
Findings from the group’s research will go directly back into teaching activities, Haucke says. Biochemistry students, for example, will use the new equipment for research, learning advanced microscopy techniques in the process. The collaborative research center also includes a research training group where 25 doctoral candidates will do research during the first funding period. Haucke believes the collaborative research center will yield important findings, especially for medicine, since the molecular scaffolds are especially important in cancer research, but also in understanding autism and epilepsy.
Professor Volker Haucke, Institute of Chemistry and Biochemistry, Freie Universität Berlin, Tel.: +49 (0)30 838 - 56922, Email: firstname.lastname@example.org